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DIY Stompboxes => Building your own stompbox => Topic started by: rockgardenlove on May 08, 2006, 07:32:46 PM

Title: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 08, 2006, 07:32:46 PM
So I was reading some stuff on the George Martin and the Beatles studio techniques, and it said they used to send many of their guitar tracks through an automatic double tracker.  I assume this was just some kind of delay/chorus something, but it sounds pretty cool, and was wondering if there was a stompbox type thing that might simulate this.  I really like the kind of "semi-warbly" guitar tones that you come across on the later Beatles albums, esp the White Album. 


Thanks!
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: MartyMart on May 08, 2006, 07:37:51 PM
I think that in those day's, it may well have been a tape recorder, guitar sent to the
record head and monitored from the replay head, along with the original, so there's probably
10-15 miliseconds of "delay" between them.
Combined with the "analog/wow and flutter" from tape, it would sound FAB !
I'm sure that's where "ADT" originated .... unless I remember wrongly !

MM.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 08, 2006, 07:47:06 PM
^Just read a wikipedia article on it...it is a few ms delay, and then that analog sound...

So for a live effect, the delay is easy.  I've never heard of a really "warbly" kind of effect...its not like a chorus or anything really...
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: notchboy on May 08, 2006, 08:15:11 PM
To start with, I wouldn't take a Wikipedia article as any sort of gospel truth.  A lot of them are "works in progress," to put it kindly.  That Wiki article implies that a singer can do a true double-track that's within a few milliseconds of the timing of the original track, which I find very hard to believe.

Anyway, ADT doesn't use delays of only a few milliseconds -- that's down in the flanging range, and ADT is not flanging or static comb filtering, it's more like somewhere between thick chorusing and a short slapback delay, although there is no "official" definition of what delay range is ADT.  I'd guesstimate 25-75 ms as being the ADT range; 100 ms is starting to get into short echo territory.  I would imagine that they had to run tape machines at fairly high speeds, or use ones that had very little space between the record and playback heads, to get those delays.

Remember the old MXR rack mount Flanger/Doubler?  The Doubler mode is an example of what I think of as an ADT effect.  The old Electro-Harmonix Full Double Tracking effect had a choice of two fixed delays, 50 or 100 ms if I recall correctly.  Adding some modulation makes the double-tracking less fake sounding, but it has to be very, very subtle, or it will just sound out of tune.  You want something on the order of the wow and flutter of a good tape deck, not something that will make you seasick.

btw, the "warbly" sound on Beatles recordings was usually a Leslie, right?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 08, 2006, 09:00:34 PM
^Alot of tracks used a leslie...I'm not sure...I'm talking about the kind of subtle stuff like the "While My Guitar Gently Weeps" guitar tone.

Harrison quote on the subject:

"...I was with Eric and I was going into the session and I said, 'We're going to do this song. Come on and play on it.' He said, 'Oh no. I can't do that. Nobody ever plays on Beatles' records.' I said, 'Look, it's my song and I want you to play on it.' So Eric came in and the other guys were as good as gold because he was there. Also, it left me free to do the vocal and play rhythm. Then, we listened to it back and he said, 'Ah, there's a problem, though, it's not Beatley enough.' So, we put it through the ADT (automatic double tracker) to wobble it a bit."



Title: Re: ADT-Automatic Double Tracker Simulator
Post by: aziltz on May 08, 2006, 09:17:57 PM
See i read that same account in Guitar Player and they said it was something about the engineer twisting the "oscillator" on playback.  What that means, i dunno.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: notchboy on May 08, 2006, 09:26:52 PM
Quote from: aziltz on May 08, 2006, 09:17:57 PM
See i read that same account in Guitar Player and they said it was something about the engineer twisting the "oscillator" on playback.  What that means, i dunno.

Oscillator == variable-speed oscillator (VSO) controlling the motor speed on a tape deck.  i.e. it wasn't a Leslie.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: aziltz on May 08, 2006, 09:28:02 PM
good call.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 08, 2006, 09:30:30 PM
^Hehe, thats what it said in wikipedia :P

Maybe a delay hooked up to an expression pedal then?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dave_B on May 08, 2006, 10:30:17 PM
Quote from: rockgardenlove on May 08, 2006, 09:30:30 PM
^Hehe, thats what it said in wikipedia :P

Maybe a delay hooked up to an expression pedal then?
Seriously doubt that.  Lennon had a tough time with multiple takes, especially if attempting to 'double track' his vocals.  It was easier to use the ADT than to try and get a second take from him that reasonably matched the first. 

I'm not sure if Martin or Emerick have ever detailed how they did it, but we can guess it's just tape delay.  Any manual speed control was probably an attempt to keep the machines from drifting too far apart. 

On that topic, a friend of a friend recently rented Studio 2 for a day (in the last month or so).  I never did ask if they actually recorded anything.   ;D  According to the engineers, the piano in Studio 2 is the same one used by the boys.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: bioroids on May 08, 2006, 11:02:41 PM
ADT is supposed to be "invented" by Abbey Road engineer Ken Townsend (spelling?).

IIRC it is supposed to be a tape delay with the speed varied with an LFO and mixed back with the original signal. Kinda an evolution of the "flanging" effect I suppose.

The aim of this was to avoid having to do several takes to doubletrack the vocals, but they ended up using it in everything. This is the Revolver album mainly, afterwards they just got tired of it, it seems. I don't think they ever used it on the White album and followers, but they did use the tape machine for vibrato (which is essentially the same but without mixing the original signal).

At least this is what I read in many years of searching Beatles recording info...

Luck

Miguel
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 08, 2006, 11:49:23 PM
Well, Harrison himself says that it was used on the Clapton solo on While My Guitar Gently Weeps...


In any event, is there a box to get that kind of tone?  Its definetly not just straight guitar.  Any tape-warble synth?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 09, 2006, 12:04:44 AM
You can kinda get it from a TC 2290, Korg SDD-3000, Korg DL8000R, and Eventide Eclipse.  The trick is you have to vary the delay time as well as the pitch - most delays have LFOs applied for pitch, but to really do it you have to LFO the delay time.

The Line6 DL4 can do a pretty decent job if you use an expression pedal on the tape echo model's wow.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 12:09:35 AM
Bit too expensive...

Nothing DIY-able?  I just want that very subtle warble.  Would some type of very subtle vibrato get that effect perchance?  Something like an LFO hooked up to both a vibrato and a delay at the same time?

I need that sound!
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dave_B on May 09, 2006, 12:15:39 AM
Quote from: rockgardenlove on May 08, 2006, 11:49:23 PM
Well, Harrison himself says that it was used on the Clapton solo on While My Guitar Gently Weeps...


In any event, is there a box to get that kind of tone?  Its definetly not just straight guitar.  Any tape-warble synth?
I guess it's time to get the White Album out.  I can't recall any unusual effects on that track.  That means very little, by the way.

For what it's worth, I couldn't find any documentation on it in the Lewison "Chronicles" book.  It mentions it was done on Sept 6, 1968, Clapton used his Les Paul, and gives the impression he didn't spend a lot of time on it, but that's about it. 
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 09, 2006, 12:21:25 AM
Dave,

Listen to the piano - it, the vocals, and the rhythm and lead guitars are ADT'd, as are many White Album tracks (Glass Onion and Piggies come to mind).  It's on a lot of post-Revolver tracks, as are Leslie and Fender Tremelo.

I read an interview with Emerick where he described Townsend's ADT as just playing around with the motor speed of a second tape deck with an LFO.  Totally random, and never reproducable.  Townsend also either invented or was one of the very first to use flanging - literally pressing lightly on the flange of the tape reel to slow down the playback or recording speed.  From there it was a short step to ADT.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 12:23:42 AM
^Everything just sounds very slightly off...the backing electric guitar seems really effected up, and the lead has something going too...

It's definetly not a huge in your face type effect.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: SeanCostello on May 09, 2006, 01:35:49 AM
Pretty sure it is just tape flanging. Same recording played back on 2 tape decks, with the speed of 1 of the tape decks being varied (using the VSO mentioned above to control the tape speed). The tape speed would have to be periodically adjusted, in order to avoid the delay between the 2 units becoming too great, or to avoid through-zero flanging if this is not the desired effect. Since it was a human controlling the tape speed, the pitch change would be more erratic than if driven by an LFO, resulting in a much more interesting sound.

In one of the Beatles books I have, the engineer who applied ADT to Clapton's solo in While My Guitar Gently Weeps talked about how boring it was wiggling the oscillator speed knob for hours...

Sean Costello
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: bioroids on May 09, 2006, 07:32:25 AM
Quote from: LyleCaldwell on May 09, 2006, 12:21:25 AM
Dave,

Listen to the piano - it, the vocals, and the rhythm and lead guitars are ADT'd, as are many White Album tracks (Glass Onion and Piggies come to mind).  It's on a lot of post-Revolver tracks, as are Leslie and Fender Tremelo.

The effect you mention is very notable, but I think it's not ADT but plain vibrato. It's a very different sound, but is made by the same means of wiggling the speed of a tape machine, either with an LFO or manually. The difference is, for ADT, you need to do it on separate machine so you can mix it with the dry sound.

On the White Album there's a lot of vibrato going on, showcased even in the little track Wild Honey Pie.

A way to get vibrato is to mute the dry signal on most phasers or choruses (there are mods for the Ross phaser I think, to do this). I don't know how close to the tape vibrato can you get with this simple means.

I wouldn't trust too much on the Beatles talking about technical facts  :icon_wink: but Harrison did say that Townsend should receive a medal for his invention (back in the Revolver days).

Luck!

Miguel
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: RDV on May 09, 2006, 07:43:30 AM
The Easyvibe on "Vibrato" mode certainly wobbles the sound a bit. At faster speeds it definitely emulates that sound IMO.

YMMV

RDV
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Mark Hammer on May 09, 2006, 09:02:58 AM
I feel like I'm at a kids' birthday party, watching "pin the tail on the donkey" and everyone is sticking the tail on the donkey's face or back.  Close but no cigar.

Whether it is tape, digital, Leslie, analog or rubber bands and masking tape makes little difference.  The key consideration is what makes something *sound* like two distinct individuals doing the same thing.  Chorus pedals have historically been an attempt to simulate the sound of....well, a chorus...several individuals singing/playing the same material in synchrony, or at least attempted synchrony.  One copy of the signal "takes the lead" and a second copy falls behind and catches up in periodic fashion.  You can achieve that by slowing down an analog sample via a bbd, a digital sample, or by twiddling the motor speed control on the tape deck.  Hell, if you wanted to, you could start two turntables off with the same track and twiddle the turntable speed control in the corner and do it too.

Is that enough?  Not really.  One needs to keep in mind what the human ear is able to derive and what its attention is drawn to as the stagger between multiple versions changes.  If the stagger is very close, what is noticed is the notches/cancellations created by two versions of the same content closely spaced in time.  That's flanging.  If the stagger is slightly larger/longer, perception of the notches declines and perception of pitch deviations tends to dominate, as well as an audible asynchrony.  That's chorus. 

What people generally refer to a "automatic double-tracking" is a similar kind of stagger but somewhat longer, probably more in the 20msec+ range.  How is this different, and how is it different than slapback?  Easy part first.  With slapback, the amount of stagger never changes, whereas with double-tracking it does.  The second voice is always discernible as a repeat with slapback.  Now the harder part.  With ADT, the stagger will occasionally (more in a second) get shorter such that it doesn't *always* sound like a discernible repeat.  But will the stagger be, or more importantly should it be, periodic like an LFO-based chorus?  I think the answer can be found by imagining yourself as a singer in a studio trying to repeat on playback what you just sang and recorded.  You listen through headphones (put on your best pensive look with hands clasping the headphones, kiddies, and crowd that spit barrier in front of the Neumann U47) and try to remember what you just did to the best of your ability.  How accurate will your pacing be?  In other words, as you try to recreate the parsing of words, the emphasis, the periods of silence, etc, what will your margin of error be?  Likely you will occasionally sing the same thing at almost the same time as the first track, but more often than not, you will be in the vicinity of 25-50msec off, simply because of reaction time, and relative accuracy in preparing movements/actions.  The end result will sound like two individuals because of that asynchrony, but here's the big magic difference in my view: the pitch deviation will be negligible because the stagger will be a function of the duration of silences or sustain of a note, NOT because of a graduated catching up and slowing down as in the case of a chorus.

It IS possible to get close to mimicking this with a sampled-delay (analog or digital).  I have one of those old blue rackmount MXR digital delays, and the LFO modulation can be applied to any of its 8 delay ranges.  Fortunately, because digital delays of that era had limited delay-modulation (the MXR swept over a maximum 4:1 range), it was easy with that unit to set it for, say, sweep between 30 and 40msec delay.  The sound is one I like to describe as being a bit like Pat Metheny, which is chorus-like but has a different ethereal quality that comes from the easily discernible stagger between wet and dry.  I haven't heard the "bounce" function on the old Eventide delays that Steve Giles is fond of, but I imagine that might introduce an element of realism too, and is possibly what distinguishes tape-based ADT from totally electronic attempts.

Ideally, though, an ADT would have only the faintest pitch modulation, and would probably use time compression to vary the duration of the gaps between notes.  That is probably not the sort of thing you can do in real time, but is consigned to the realm of post-production.  Choruses, of course, are kind of stuck when it comes to doing such things, because they have to always speed up the sample output of the audio to catch up and slow it down to lag.  While this will shorten and lengthen the gaps between notes, it will also distort the pitch as well.

For the time being, though, and for the adventurous, simply double the clock capacitor on your chorus pedal, to shift the range over.  You can easily tack a second parallel cap on the copper side of the PCB for a brief experiment.  You will notice two things immediately.  That whining.  Please, God, stop that whining!!  It's driving me INSANE!!! :icon_eek: :icon_mad:  The other thing you'll notice is that your depth control will need to be turned way down and may not even have the degree of sensitivity needed to dial in just a touch of modulation.  These two phenomena result from a) the clock frequency being much lower than the lowpass filtering can filter out, so much more audible, and b) the perceptibility of pitch changes at different delay ranges  (flanging changes pitch too, but you don't really notice it because at that delay range it is minimal; longer delays = more pitch deviation).
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: alteredsounds on May 09, 2006, 09:56:39 AM
Have a look for my thread about the '70's Resounder stereo ADT / Flanger I posted a couple of weeks ago.  Very nice sounding.  Might be 'clonable'.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 09, 2006, 11:33:09 AM
Quote from: Mark Hammer on May 09, 2006, 09:02:58 AM
I feel like I'm at a kids' birthday party, watching "pin the tail on the donkey" and everyone is sticking the tail on the donkey's face or back.  Close but no cigar.

Mark,

I think that's not quite fair.  Some of us were talking about emulating the EMI ADT, not a box that would just sound like a doubled vocal.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Ge_Whiz on May 09, 2006, 11:43:28 AM
On a more practical note, I recall that the Danelectro 'Reel Echo' pedal has a 'wow and flutter' emulation which might get you close to, er, something.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Mark Hammer on May 09, 2006, 12:01:26 PM
Quote from: LyleCaldwell on May 09, 2006, 11:33:09 AM
Quote from: Mark Hammer on May 09, 2006, 09:02:58 AM
I feel like I'm at a kids' birthday party, watching "pin the tail on the donkey" and everyone is sticking the tail on the donkey's face or back.  Close but no cigar.

Mark,

I think that's not quite fair.  Some of us were talking about emulating the EMI ADT, not a box that would just sound like a doubled vocal.

Well, you're right.  It was little more dismissive than was warranted.  Apologies for the appearance of harshness.  On the other hand, even the EMI-ADT is attempting to mimic something, so for me one has to start by asking "How do humans perceive the phenomenon we're trying to emulate?", since it is a psychological phenomenon we are trying to emulate (or emulate an emulation of).  Once you click into the auditory cues that people use to infer that it's two individuals playing/singing the same material, it becomes a lot easier to figure out what sort of technological requirements could achieve that, or come closer to doing so. 

Your suggestions re: the various digital delay lines that have modulation capabilities are bang on, and line up with my experience using the MXR unit.  In theory, anyways, it should be possible for any delay line that can apply subtle modulation to that delay zone between 20 and 50msec or so to get reasonably close approximations.  If the modulation can be made less periodic, via electronically-derived random fluctuations, or via hand/foot control, so much the better.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 09, 2006, 12:55:26 PM
I've had good luck using the Eclipse for ADT using the random LFO waveform.  Still periodic, but as it doesn't have any rhythmic correlation to the music played, the ear doesn't perceive a periodic pattern.

But that's an $1800 device.  And the subleties that are apparent on a recording would be lost on stage. I would bet most people would find a Deluxe Memory man set to no feedback with a fast delay time in vibrato mode to be very convincing (particularly if you use "my" mod and replace the 100K input resistor with a 1M pot and keep it in the 500K-1M range so pickups don't get so loaded down).
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dirk_Hendrik on May 09, 2006, 01:12:10 PM
One device with the nature that Lyle describes comes to mind. The Carlsbro ADT, which is, when set in the ADT setting like a chorus which can be set (rate at almost 0) to a chorus without the (percievable) modulation. Especially for UK forumites (as they're sold most in the UK) get one:
(http://www.dirk-hendrik.com/images/Carlsbro_ADT.jpg)
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: vanessa on May 09, 2006, 03:49:12 PM
I have found (for vocals anyway) the easy way to get a perfect double tracked vocal without having to do 50 takes (in fact I can normally get them on 1 or 2 takes) is to do it this way:

(BTW thank God for DAW's!)

I have the vocalist get the perfect take for the first track (obviously),

I then have them record a second "doubling" take (hold down the laughter just for a moment).

I usually find the big problem with double tracking is at the very beginning of or at the very end of a phrase. Usually the problem is lining up the very first uttering of the line that's being sung with the original perfect take track. Also at the end of a phrase, say when one's holding a note and overshoots or undershoots the phrase. If they overshoot at the end you can very easily fade out the double track with the original.

If they overshoot or undershoot at the beginning of a phrase I just copy and paste the very first uttering of the phrase from the first track to the very beginning of the second "doubled" track. Then I use a cross fade on the second track to smooth out the transition. And for just a few seconds of work I got instant ADT. What's cool is it has all the natural modulation of two people singing the same phrase, but with out all the headache of countless takes.

I'm sure this is done all the time in studios. But in case someone here is not familiar with it I thought I'd post it.




Title: Re: ADT-Automatic Double Tracker Simulator
Post by: SeanCostello on May 09, 2006, 04:30:57 PM
Quote from: Mark Hammer on May 09, 2006, 09:02:58 AM
The end result will sound like two individuals because of that asynchrony, but here's the big magic difference in my view: the pitch deviation will be negligible because the stagger will be a function of the duration of silences or sustain of a note, NOT because of a graduated catching up and slowing down as in the case of a chorus.

OK, try this experiment: Record yourself singing a single note. Then, double track this note. Try to get NO beating between the two notes.

Unless you are a freaking robot, this is impossible. The human voice has a certain amount of random jitter in it, and tends to drift all over the place. You will ALWAYS have beating between notes, regardless of the timing between individual notes or syllables.

For guitar, it is somewhat easier to have the same basic pitch between notes, if you match up the tuning correctly. However, unless you pick each note in a double tracked line in EXACTLY the same position with EXACTLY the same amount of force at the EXACT microsecond as the original recording, you will have phase differences between the notes, which is what you have with mild amounts of chorus anyway.  Plus, guitar strings almost always have a little bit of attack-dependent pitch bend, due to tension nonlinearities, which may be too subtle to hear on their own, but will cause beating effects when double tracked.

Sean Costello
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Mark Hammer on May 09, 2006, 05:01:21 PM
I yield.

But how would one mimic that?  I don't know about you, but I've NEVER heard beats in any of the chorus devices I've used, and there's a lot of em.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: SeanCostello on May 09, 2006, 06:03:44 PM
Quote from: Mark Hammer on May 09, 2006, 05:01:21 PM
I yield.

But how would one mimic that?  I don't know about you, but I've NEVER heard beats in any of the chorus devices I've used, and there's a lot of em.

Beating = detuning. Sinusoidal driven choruses will have time-varying beat patterns. Triangle wave (Roland Dimension) and pitch shifter based choruses will have a steady number of beats per second for a given input frequency.

The easiest way to emulate "true" double tracking would be to simply emulate the overall time lag and detuning, using a longer delay line (20-40 msec) with a semi-random LFO, with a fairly low depth. Thiw would be close to the Beatles ADT.

If you want to emulate the phrasing differences, you could implement a transient detector, and use it to crossfade between two delay taps, with a random delay time set every time there is a new transient. This would generate the widely varying delay time Mark discusses, without the excessive pitch modulation that would result from trying to generate this variation with a single delay tap.

Sean Costello
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: vanessa on May 09, 2006, 06:40:54 PM
Or you could do what I have posted above and be done with it...

:icon_lol:
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 09, 2006, 06:43:03 PM
Vanessa,
That is one of many ways to do it after the fact in the studio.  I took the thread as asking more about pedals/effects to do it in real time.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: MartyMart on May 09, 2006, 06:51:31 PM
Vanessa, there's a new plugin ( I forget the name ) which will "pull in" double tracks
and harmony vocals to "match" the lead track !!
It copies the timing from the lead to the others, at "sample" level !!
Just thought you'd lke to know :D ( saves a LOT of time )

MM.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 06:58:14 PM
I've created a monster thread  :icon_razz:


So, it seems to me at least, a bit of vibrato, with a bit of delay, and a bit of chorus should come somewhere close?  All together with an irregular LFO or what?  Set the LFO off sync from the music?  I see there's definetely no stompbox for this yet...

I'd say a very fast shallow vibrato, with ~20ms delay(maybe have the delay length hooked up to an LDR LFO?) and then a chorus...how fast for the chorus?  Mid speed?


This would be fun to put in one big box :)

Title: Re: ADT-Automatic Double Tracker Simulator
Post by: vanessa on May 09, 2006, 07:30:31 PM
Quote from: MartyMart on May 09, 2006, 06:51:31 PM
Vanessa, there's a new plugin ( I forget the name ) which will "pull in" double tracks
and harmony vocals to "match" the lead track !!
It copies the timing from the lead to the others, at "sample" level !!
Just thought you'd lke to know :D ( saves a LOT of time )

MM.

Marty! I've seen one from Waves that lets you run the plug-in on the original track letting you do very minor pitch shifting, modulation, and slight delay. To me it never really sounded like true double tracking. I would be interested in checking out the one you're talking about. The last time I fiddled with ADT plug-ins was about a year or two ago and at the time I did not find anything that sounded like you would want it on a professional release. I'm sure they've made improvements.

As far as live/real time goes... There's a few rack gear units (and I'm sure pedals out there) that come close if not nail it for live use. It's when you got the 'cans' on is when you really can tell (on a recording it needs to be on the money). The Abby Road ADT does not sound like it was a 'real time' type machine. In a shoot out I'm sure I would be finished putting the finishing touches on my tracks (using my method) long before the valves had warmed up on their reel-to-reels. As far as that 'tape' or 'tube' vibe? Just record it to tape (tube preamps) and dump it into your DAW (Protools etc.). Even with dumping the tracks I would guess the process still would be faster with similar results.

Title: Re: ADT-Automatic Double Tracker Simulator
Post by: notchboy on May 09, 2006, 07:46:30 PM
Quote from: Mark Hammer on May 09, 2006, 09:02:58 AM
I feel like I'm at a kids' birthday party, watching "pin the tail on the donkey" and everyone is sticking the tail on the donkey's face or back.  Close but no cigar.

[vast amounts of text deleted]

And I feel like I'm at a birthday party where a kid walks up to the donkey, announces that everyone else got it wrong, and then pontificates for 45 minutes about "the tail definitely isn't here... or here... " then continues on about the physiology of the hindquarters of the donkey for another 45 minutes...  :icon_rolleyes:

Meanwhile, everyone else has taken their masks off and is having a great time eating birthday cake.    ;D
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 09:28:50 PM
I'm still plotting my effect, I'm choosing to skip over all this raffle.  No offense meant to anyone who participated in the spam :)


So, here's my proposal:

Vibrato-pretty fast, and shallow,
Delay-hook the delay length up to an LFO that varies between 10-20 ms or so.
Chorus-Speed undetermined..how deep too?  I'd say pretty slow though, and medium depth.  What are your opinions?

So this would be my proposed setup:
   in
     |
     |
   panner
   |    |
  dry  wet(effects)
   |    |
   \    /
     out
      |
      |




Now, questions I have that I'd appreciate some info on:

Should the effects be put in series or parallel?  And if in series, what order would be optimum?
General info on LFO speeds, etc.  Should there be one LFO for all?  Should certain effects share an LFO?  What do you guys think?


Thanks!
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dave_B on May 09, 2006, 09:49:42 PM
Quote from: notchboy on May 09, 2006, 07:46:30 PM
Quote from: Mark Hammer on May 09, 2006, 09:02:58 AM
I feel like I'm at a kids' birthday party, watching "pin the tail on the donkey" and everyone is sticking the tail on the donkey's face or back.  Close but no cigar.
[vast amounts of text deleted]
And I feel like I'm at a birthday party where a kid walks up to the donkey, announces that everyone else got it wrong, and then pontificates for 45 minutes about "the tail definitely isn't here... or here... " then continues on about the physiology of the hindquarters of the donkey for another 45 minutes...  :icon_rolleyes:
Not cool.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 10:05:16 PM
So erm, sorry to intrude, but could someone pay the slightest bit of attention to my question and stop bickering?  Please?  Don't mean to seem demanding, its just that the meaningful posts get lost in the flood of all this other stuff.

Thanks
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 09, 2006, 10:13:18 PM
I would suggest the delay should range from 20-60ms, depending on how pronounced you want the effect.  The 10-20ms range will sound too much like flanging, I would think.  Definitely some mono phase cancellation.

Quote from: rockgardenlove on May 09, 2006, 09:28:50 PM
I'm still plotting my effect, I'm choosing to skip over all this raffle.  No offense meant to anyone who participated in the spam :)


So, here's my proposal:

Vibrato-pretty fast, and shallow,
Delay-hook the delay length up to an LFO that varies between 10-20 ms or so.
Chorus-Speed undetermined..how deep too?  I'd say pretty slow though, and medium depth.  What are your opinions?

So this would be my proposed setup:
   in
     |
     |
   panner
   |    |
  dry  wet(effects)
   |    |
   \    /
     out
      |
      |




Now, questions I have that I'd appreciate some info on:

Should the effects be put in series or parallel?  And if in series, what order would be optimum?
General info on LFO speeds, etc.  Should there be one LFO for all?  Should certain effects share an LFO?  What do you guys think?


Thanks!

Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 10:23:33 PM
Alright, thanks man ;)
Really appreciate it.
Still have a few questions gone unanswered though, namely chorus speed, and vib speed.

Would an overall volume LFO be worthwhile?  Just to give it a bit of an overall less predictable trem sound at the same time?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 09, 2006, 10:28:36 PM
I don't think you'll need to do chorus AND vibrato.  Just LFO the delay time and slightly LFO the pitch and the rest should take care of itself.  I also don't think you need any trem - there will be phase relationships changing all the time, with some frequencies dipping and others accentuating, so there will be perceived volume fluctuations without doing an actual trem effect.

But if you do want some chorusing, I wouldn't LFO the chorus - just clone the output of the wet LFO and delay it by 30ms or so (no feedback) for a nice stereo spread.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 11:00:22 PM
Alright...

So far I've been considering using the PT-80 delay, would you say that's a good choice?  Or might it be better to use a AD-3208 delay because its analog?  (Both are at GGG.)

Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dave_B on May 09, 2006, 11:01:33 PM
Tom Scholz did some work along these lines too.  Here's the patent (http://www.pat2pdf.org/patents/pat4489439.pdf) for his reverb / doubler.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 11:09:31 PM
Interesting...with my limited electronic abilities, one of the simpler forms seems to be just a variable delay.

Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 09, 2006, 11:20:07 PM
Alright, so just thought of something else.

Say if I wanted to use it for vocals, would I need any extra fancy stuff?  I don't need phantom power, I just want to use a Shure '58 or so. 

Also, if I wanted to send it the output from my Presonus Firebox(recording interface) and then loop it back into an input, would that require extra work?  Something to clear up possible impedence issues?  I think a standard "line out" is usually lower impedence than a guitar pickup. 

Thanks!
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: stm on May 10, 2006, 10:39:11 AM
To put it in physical terms, the tape delay has the following parameters to take into account:

a) Time delay -- between 25 and 75 msec
b) Frequency response with slightly less highs -- the antialias filters on the BBD take care of this aspect
c) Eventual compression effect of the tape recording -- again the BBD introduces some compression
d) Wow and flutter -- here is the key

Wow are slow fluctuations that can be associated to the speed servo control system. These are expected to be slow and shallow, thus a LFO around 1 Hz with shallow modulation will do.

Flutter are faster fluctuations that can be associated to the mechanical tape transport mechanism (pinch roller, elasticity of the rubber bands involved, gears, etc.)  This can be implemented as one or more faster LFO's, or as a pseudo random LFO.

Combining the aforementioned LFO's into a single modulating signal might do the trick. The key is that the wow and flutter LFO's must be asynchronous.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 10, 2006, 11:07:04 AM
So the "wow" should be slow, that makes sence.  I was considering using a chorus for the "wow"...would that be a good choice?  What kind of effect should be applied do you think?

And for the "flutter" effect, I was thinking a vibrato, going fast, and being set really shallow...sound good?

And I'd top that all over with that LFO'd analog delay?  Does that sound right?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 10, 2006, 06:17:16 PM
Bump wooples!
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: stm on May 10, 2006, 06:35:46 PM
Hi,

What I meant is use a single BBD, like an MN3008 or BL3208 would be great here due to the larger delay than a typical MN3007 et al.

You need at least two LFO's, one slow, one fast.  Mix them and use this compound signal to modulate the BBD clock.

Last but not least, mix the dry signal with the delayed signal and you are set.

As an idea, the slow LFO could be sinusoidal, while the faster one could be a filtered squarewave (pseudo triangle) perhaps for a more drammatic effect.  YMMV.

As a starting point, you may consider a chorus circuit but with two different LFOs that simoultanueously modulate the BBD Clock IC.  A compander on the wet signal might be advisable for optimum noise performance.  Again, YMMV.

Cheers.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: DuncanM on May 10, 2006, 07:25:52 PM
Or even use an LFO, the speed of which is modulated by a second LFO - this gets rid of the regular modulation that we associate with "chorus" or "flange". Might be more subtle and "organic"...
Slightly different from just adding the output of two LFO's together.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 10, 2006, 08:51:15 PM
^Alright, thanks guys.  I'll take all that stuff into consideration.

If I use a chorus too, I'm assuming the chorus should come before the delay?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 10, 2006, 09:49:14 PM
No, the chorus should only be applied to the delay.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: zachary vex on May 10, 2006, 11:33:30 PM
i read through the whole thread and never found the word "capstan."  as i recall, Geoff E. taped lumps around the capstan of one machine to introduce variations in tape speed by simply changing the capstan's diameter unevenly.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: LyleCaldwell on May 10, 2006, 11:48:35 PM
Never seen that in any interview.  Numerous people have specifically mentioned the knob controlling the voltage fed to the second tape deck.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: TELEFUNKON on May 11, 2006, 12:46:56 AM
Quote from: zachary vex on May 10, 2006, 11:33:30 PM
i read through the whole thread and never found the word "capstan." 
in reply#47 stm mentioned the "pinch roller" (reminded me of "capstan"):
QuoteFlutter are faster fluctuations that can be associated to the mechanical tape transport mechanism (pinch roller, elasticity of the rubber bands involved, gears, etc.) 
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: SeanCostello on May 11, 2006, 01:26:43 AM
Quote from: zachary vex on May 10, 2006, 11:33:30 PM
i read through the whole thread and never found the word "capstan."  as i recall, Geoff E. taped lumps around the capstan of one machine to introduce variations in tape speed by simply changing the capstan's diameter unevenly.

Wow. That is a neat idea. I have seen something similar in a Donald Leslie patent, where a frequency shifter (based upon something mechanically rotating, of course) is driven by a "cam" that is irregularly shaped, in order to introduce a quasi-random deviation to the shift amount.

Makes me wonder if Boards of Canada do something similar to their tape processing...

Sean Costello
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: MartyMart on May 11, 2006, 06:27:58 AM
Quote from: SeanCostello on May 11, 2006, 01:26:43 AM

Makes me wonder if Boards of Canada do something similar to their tape processing...

Sean Costello

HA ! they are the "Kings" of modulation !  :D
Couldn't this be done with the following three pedals :
A "Y" lead to split the signal ( a wet and a dry feed)
A delay pedal set to around 60ms - no repeats
A chorus, slow with blend at 100%
Another, or phase with blend at 100% for vibrato set faster 
Both signals back together with "Y" lead No2 or a mixer stage ...?

MM.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Mark Hammer on May 11, 2006, 08:55:46 AM
Even "lumps" on a capstan will result in a certain periodicity, though clearly they will result in an irregular wavform (i.e., not the same old triangle).  Perhaps, from an electronic perspective, the optimal solution is to use either a noise-based CV/modulation source (like the Maestro S&H), or several unsynced LFOs mixed together (as STM suggests).
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: lovric on May 11, 2006, 09:47:19 AM
while you are on the track to make a good ADT i'd like to share what i've red in a Carlos Rios interview.

Carlos Rios was a guitar player to, now probably forgotten, Gino Vannelli and later was working as a musical director to Lionel Ritchie. memorable little solo in "i just called to say i love you".

in the days of Vannelli, Carlos had thick and filling tone beyond distortion. he explained that after recording down the solo guitar parts, while retaining the same settings and tuning, the recording engineer would slow the tape 2% and he would then record dobules.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: notchboy on May 11, 2006, 03:01:07 PM
Quote from: zachary vex on May 10, 2006, 11:33:30 PM
i read through the whole thread and never found the word "capstan."  as i recall, Geoff E. taped lumps around the capstan of one machine to introduce variations in tape speed by simply changing the capstan's diameter unevenly.

IIRC it was just pieces of editing tape wrapped around the capstan.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: notchboy on May 11, 2006, 03:07:10 PM
Quote from: lovric on May 11, 2006, 09:47:19 AM
while you are on the track to make a good ADT i'd like to share what i've red in a Carlos Rios interview.

Carlos Rios was a guitar player to, now probably forgotten, Gino Vannelli and later was working as a musical director to Lionel Ritchie. memorable little solo in "i just called to say i love you".

in the days of Vannelli, Carlos had thick and filling tone beyond distortion. he explained that after recording down the solo guitar parts, while retaining the same settings and tuning, the recording engineer would slow the tape 2% and he would then record dobules.

6% is about a semitone, so 2% seems like a lot of detuning.

I've heard of detuning the guitar by the same amount as the tape speed change, so that when played back at the correct speed, the tuning is correct but the harmonics are detuned, giving a nice chorus effect against the original track.  But the speed change has to be very small.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Mark Hammer on May 11, 2006, 03:12:37 PM
Actually there is no pitch change in the final recorded product.  The deck is slowed down and the player simply retunes and plays along, in tune.  The effect achieved is one of altered envelope.  That is the attack and decay components of the instrument are perceptibly different.  Les Paul and Frank Zappa were constant users of that technique though I suspect more extreme users as well.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: MartyMart on May 11, 2006, 06:42:12 PM
Quote from: Mark Hammer on May 11, 2006, 03:12:37 PM
The deck is slowed down and the player simply retunes and plays along, in tune. 

That's funny ..... I dont know many guitarists that "play along in tune"  :icon_lol:  :icon_wink:

I'm just kidding and have too many years of "digital keyboard" tuning etched into my brain, so
"tuning" is a nightmare for my ears !!
I even have to "re-tune" some samples of strings/brass etc ... they are never quite right ....
I'm thinking about geting the "Buzz Feighton" ( spelling? ) system on my strat
MM.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: spinoza on May 11, 2006, 11:30:55 PM
YAMAHA E1010 analog delay? I got mine for 75$, it has modulation depth/speed pots and sounds very sweet.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 12, 2006, 02:44:33 AM
So here's my semi-final verdict. 

Delay+Chorus: 20-75 ms
LFO(controls next LFO speed)->LFO(controls chorus and delay rate)



That sound right?  A delay and a chorus, hooked up to an LFO, thats speed is determined by another LFO.  Effect order is delay->chorus.  I'll then have a panner to pan from dry to wet.  I'll then put in a few FX loops, making it like this:


      in
      |
      |
(dry)panner(wet)
     /   \
    |    FX loop
    |    delay
    |    FX loop
    |    chorus
    |    FX loop
    \    /
      out
       |
       |



This should allow a large amount of control over the wet side.  I can use the FX loops to plug in more standard type effects, that don't need special LFO setups.  Things like a compressor, stuff like that.
Thoughts?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 13, 2006, 06:24:38 PM
I just remembered that when I build this I'll be finished with my Fender tube build project.  That means I can do stereo.  Does anyone have a schematic of a stero panner hooked up to an LFO anywhere?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Quackzed on May 13, 2006, 11:28:24 PM
I've got pretty good double tracking from a crummy cassete recorder ;D
You just record your takes on the cassette recorder and then play them back from the casette deck into your pc (original track) .then rewind and record another pass of it onto another track on your pc(doubled track).
    Hopefully they will line up enough that you can make a few snips here and there to one or the other and prevent them from going too out of sync. :P  sounds less cyclic than lfo's to me and also sometimes the tracks catch up and pass each other for weird "merge phase" anomalies  :icon_cool:
   
  I think i've read about the beatles also synching recording consoles by the ac frequency feeding power to the consoles..  :)
:icon_cool: ??? 8) 8)
"George, turn up all the knobs... "
   
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 14, 2006, 12:23:50 AM
This is for live stuff though...

Any more info on an LFO stereo panner?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Quackzed on May 14, 2006, 11:30:14 AM
i don't know about the lfo though...
                 So here's my semi-final verdict. 

                 Delay+Chorus: 20-75 ms
                 LFO(controls next LFO speed)->LFO(controls chorus and delay rate)

sounds good to me and i think with a really slow lfo speed for the first lfo and a slightly (slghtly) faster one for lfoing the lfo... :D for more "random" slight warble...it will be fab

        oscillating the oscilators, boosting the boosters, overdriving the overdrives and feeding the feedbackers feedbaaaaaAAAAAAAAAAAAAAA/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/*poof*
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 14, 2006, 03:17:34 PM
So, what projects should I base this project off of?  I was thinking a PT-80 for the delay, but what should I use for the chorus?  Suggestions?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Processaurus on May 15, 2006, 07:39:37 PM
Just a quick thought - some compression or expansion on either the dry or delayed signal might help recreate the feel of two instruments/players, by changing the envelope of one of them, so the typical chorus sound would be less obvious.  A little EQ of some kind might help too, to attempt to mimic what happens when you shift your picking hand a little, or change the angle of your pick (which can make a noticeable difference in sound, thats something that can come up when doing punch-ins).
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Quackzed on May 15, 2006, 09:02:49 PM
maybee a noise gate on the delayed signal for some variation on note attacks and decay times of notes...  would have to be a fast attack and decay and a low  threshold... could use a stereo chorus and just add a noise gate from the chorus side... then your regular signal has slightly different attack/decay character 8)

Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 15, 2006, 11:07:49 PM
Good ideas.  I'm thinking all these add in effects can be fairly standard stuff though, so I was just planning on putting these effects into wet/dry loops and then housing the chorus/delay in one main box because of the special LFO setup.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dave_B on May 16, 2006, 10:33:44 AM
Abbey Road stuff moved to the Lounge...
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 16, 2006, 07:24:54 PM
Cool stuff!


Still though, what's a good chorus, delay, and panner for tweaking?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dave_B on May 17, 2006, 12:43:59 AM
It sounds like you're getting more complicated than the original device.  The earlier advice about using one LFO to modulate another would seem to be the way to go, giving you something more complex than a typical time-based circuit.  I'm not sure you need to go to the effort of running the signal through two delay-type circuits if you can properly modulate one of them. 
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 17, 2006, 01:01:23 AM
^Yeah thats what I'm gonna do.  I'm gonna have a subtle delay hooked up on the same LFO though.  So the delay and chorus will correspond, and then at the same time I'll have a wet/dry loop built in just for general use. 


I've decided not to do the stereo LFO panner.  I'm just gonna put in two outputs, because two different amps=two different tones=sounds like more instruments.  And its an easy feature to add.


So what delay+chorus should I use?  I was considering using a PT-80 for the delay, and then a Small Clone with a jack to plug in the new LFO system...
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dave_B on May 17, 2006, 10:39:24 AM
If you don't have either, I'd start with just the PT-80.  Build a couple of outboard LFO's and use an opto to interface them to the delay.  It doesn't sound like anyone has done this before, so you're probably going to have to experiment and tell us
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Mark Hammer on May 17, 2006, 10:59:29 AM
Small Bear carries an 8-pin version of the MN3208 - http://www.smallbearelec.com/Categories.bok?category=ICs+Delays+and+Echo

I *think*, but am not absolutely 100% certain, that the BL3208 has the same pin out as the MN3207, just twice as many stages.  Assuming they do have the same pinout, if one had a 3207-based chorus pedal (and there are loads of those at decent prices), subbing the on-board MN3207 with one of those 8-pin BL3208s would double your delay time, without having to change anything else like the filtering.  A chorus whose delay range went from 5-20msec would now go from 10-30msec.  One would likely need to adjust the depth control a bit though, because the same amount of clock modulation at longer delays will require Gravol for all users and listeners.  A simple fix is to simply stick a fixed resistor in series with the input lug of the depth pot.

So, two questions:  1) Who knows what bargain-basement chorus pedals are currently sold that use through-hole (no surface mount) MN3207 BBDs?  and 2) Is the BL3208 identical in pinout to an MN3207?

EDIT/UPDATE:  Did some digging and the BL3208 can successfully be plugged into the socket where an MN3207 used to be.  Pin for pin compatible.  I think we may have a winner here.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Quackzed on May 17, 2006, 01:07:27 PM
i got my rocktek(3205) ch01 pretty rockin by tweaking the d-time cap and adding a chorus/vibrato switch plus i added a fast /slow switch AND a trem switch (also makes the led go on and off ;D) PLUS i found a spot for a switch that changes the waveform of the chorus... kinda ramps up then starts over, ramps up again... sounds just like sci/fi startreck or Robalard... remember him? the alien who loved all kinds of candy bars? then tried some "earth fruit" and discovered it was yummy and not bad...
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 17, 2006, 07:58:30 PM
I like Mark's question.  I need a chorus to base my project on :)
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 19, 2006, 08:19:50 PM
So there are no DIY chorus's!?  I'm suprised!
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Mark Hammer on May 20, 2006, 09:38:55 AM
There are several over at Tonepad, but after clones of the CE-2 and Small Clone became available (not to forget the completely DIY Zombie from John Hollis), I suspect people ran out of interest in making others the way there is no end to the fascination for new fuzzes.  Unfortunately all 3 of those chorus units employ an MN3007 for which the 3207 (and 8-pin 3208) can not just plug in and work without modification.

What we need is a project for an MN3207-based chorus so that a BL3208 can be plugged in for ADT experiments.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Dave_B on May 20, 2006, 08:02:47 PM
If you can wait until August, this book (http://www.recordingthebeatles.com/) promises to explain it all.  The authors were interviewed for the current TapeOp mag and they mention a big section of the book being dedicated to ADT.

This book has been promised for such a long time, I forgot about it. 
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 21, 2006, 06:14:11 PM
http://generalguitargadgets.com/diagrams/IbanezCS9.gif
Ibanez CS9 chorus.  Does that look right?  I think that has the right chip.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 22, 2006, 03:17:17 AM
Just a little bump so it won't pass over to the second page ;)

Will that CS-9 work?  Anyone know where I can get a PCB layout?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 22, 2006, 06:58:11 PM
Bump?
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: Mark Hammer on May 23, 2006, 01:12:05 PM
Yes, that will work.  never seen one myself, or a layout.
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 23, 2006, 06:43:43 PM
Hmm alright...

That would be horrible to perf...I think a layout is the only option.  I'd like to eliminate as much as possible though first.  I won't be needing stereo for the chorus, how might I take that out?  I also don't want any buffers, etc. 

I think I have a basic idea of what to do, I just want to verify.


Thanks!
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on May 25, 2006, 04:26:25 AM
Bump  8)
Title: Re: ADT-Automatic Double Tracker Simulator
Post by: rockgardenlove on December 02, 2006, 06:36:29 AM
I'm back!

I've been experimenting with LFO circuits to find which ones I want.  Simple op-amp ones are turning out the best...nothing too special going on with them.

I'm using a pretty fast LFO to change the speed on a slower one...sounds pretty cool indeed.  They're hooked up to a simple trem setup just now...haven't used them on a delay yet.

I think I'll base it off the PT80 delay. 

I'll be posting schematics and maybe some clips up here, if you're interested. 

More ideas/comments/facts/anything is welcome!  Post everything you know, it helps!


Title: Re: ADT-Automatic Double Tracker Simulator
Post by: dr on December 02, 2006, 11:54:46 AM
......somewhere in my magazine collection here, I read that effect was done by wrapping white cloth adhesive bandage tape around either the pinch roller or the capstan-if I remember correctly......I am looking for it today..............dr
Quoteexperience is what you get when you didn't get what you wanted