Hey all
I want to make a small device that creates a small 30-50ms delay. Dry signal through one channel, wet signal trhough the other, with only one repeat. Sort of like a simulated stereo but not quite. I normally do this with my boss DD-2 but I want nice time delays and a nice spacious sound! :) I use two amps, one of which I've borrowed but when I build my own amp I think I'll put this between the preamp/tonestack/reverb and power stage...
But which BBD is best suited for this? I'd like to keep costs down but if it's necessary I don't mind paying a little more. Will a 512 stage BBD work, or should I go for 1024 stages or more. Or less? I donno :?
Suggestions very much appreciated :)
Go for 1024 stages. Get a MN3207 and a 3102. A 3207 has about 50ms max. I warn you that this effect will be very weak, and moderately useless-but good luck to you, and if you have any questions I"d be more than willing to help.
-Colin
Well the idea is to take the dry signal, then delay it slightly and play it through the other channel. I do this with my DD-2 all the time, but when I take the direct plug out, yes you're right, it's useless. But not when you have signal A hitting its amp slightly earlier than signal B. I'll record a soundclip in a while when I get my hands on some recording gear (cables ;) ) so you can tell what I'm trying to do... Hang on a sec I'll draw a pic
NO ! don`t use a 3101 when chosing a 3207!!
rather use a 3102 for clocking....
Here's the link:
www.geocities.com/smoguzbenjamin/stereo.html
By the way I have some 555's. Would they do?
Quote from: smoguzbenjaminWell the idea is to take the dry signal, then delay it slightly and play it through the other channel. I do this with my DD-2 all the time, but when I take the direct plug out, yes you're right, it's useless. But not when you have signal A hitting its amp slightly earlier than signal B. I'll record a soundclip in a while when I get my hands on some recording gear (cables ;) ) so you can tell what I'm trying to do... Hang on a sec I'll draw a pic
Don't worry, I totally understand what you're trying to do, it just seems sort of boring. No offense or anything. On the diagram you'd want to have the input going directly to the dry output, so that it's not effected by the low pass filter set at 10k you're going to need to have.
You could do this basically with the MN3102, a 3207, and a low pass filter (preferably op amp active). Have the MN3102 as follows:
Pin 1-9v
Pin 2-To MN3207 pin 2
Pin 3-Gnd
Pin 4-To MN3207 Pin 6
Pin 8-To MN3207 Pin 4
Pin 7 connected to the end of a 22pf capacitor connected to pin 5
Pin 6 connected to the end of a 5k resistor connected to a 10k pot connected to pin 5
Wire the MN3207 as follows:
Pin 3-Guitar
Pin 1-Gnd
Pin 5-9v
Pin 7 or 8-To the 10k lowpass filter.
Good luck!
-Colin
Quote from: smoguzbenjamin
By the way I have some 555's. Would they do?
Yes, but badly. Use a 3102, they're more simple and work much better with MN3207's.
-Colin
Thanks Colin! My guess is the lowpass filter goes to the delayed output ;) Whats the lpf for, to get rid of clock noise? Oh and the 10k pot etc, is that wired as a series resistor?
I wasn't really going for a stunning effect, just something that I could use instead of my boss delay to simulate stereo, so I could use the dd-2 for looooooong delay sounds :) Right, now I've also justified a SBE order :) Cheers!
Instead of using a mn3102,you can also use a cd4047,take a look at the small clone schematic,and you don´t need to modulate it...hey,you can even build the bbd clock around a single hex inverter...
Quote from: smoguzbenjaminThanks Colin! My guess is the lowpass filter goes to the delayed output ;) Whats the lpf for, to get rid of clock noise? Oh and the 10k pot etc, is that wired as a series resistor?
I wasn't really going for a stunning effect, just something that I could use instead of my boss delay to simulate stereo, so I could use the dd-2 for looooooong delay sounds :) Right, now I've also justified a SBE order :) Cheers!
Yes, yes, and yes.
Let me know how it ends up sounding.
-Colin
...and what about a pt2399 wired like the datasheet?you solve everything with a single chip,and you save that mn3207 for a nice vb2 clone :)
Quote from: Maneco...and what about a pt2399 wired like the datasheet?you solve everything with a single chip,and you save that mn3207 for a nice vb2 clone :)
He asked for BBD :)
-Colin
As long as it delays and it seemed suitable :) Plus smallbear stocks MN3207s :mrgreen: K, in a weeks time its my B-day so I will hopefully be rich and be able to buy all the stuff I need :) Sweet!
Quote from: smoguzbenjaminAs long as it delays and it seemed suitable :) Plus smallbear stocks MN3207s :mrgreen: K, in a weeks time its my B-day so I will hopefully be rich and be able to buy all the stuff I need :) Sweet!
Come on man, it's only like 10 bucks. You can pull that one off, no? Or is shipping to big?
I recently ordered a large lot of PT2399's, which I should be able to offer for pretty cheap if you decide to go that route.
-colin
If you already have a DD-2 or something similar, you should try Craig Anderton's Retro Stereo. Well... I forgot where's the schematic... If I remember well it was a very easy project.
I might just order both from SBE, he ships both... I have a breadboard, I'll just see what works the best. Sounds like the BBD option has alower parts count though. Shipping from Steve isn't bad, to ship a US pound it cost â,¬7,60. I need some other stuff from SB, mostly knobs which NO-ONE here supplies so :) I'll see. Oh as a matter of curiosity, can I put this before a power amp stage without any problems? 'cause that's the idea :)
Quote from: smoguzbenjaminCan I put this before a power amp stage without any problems? 'cause that's the idea :)
Yep.
-Colin
Thanks Colin, you help is much appreciated :)
I am just starting to get into BBD devices, so alot of folks around here are much more qualified than I to answer your question, but I see exactly where you are going. I have done this delay trick powering two combos, one on each side of the stage, and my tone really opened up, esp. when playing with a three piece.
Here is what I would do.
Input into op-amp buffer, split two signals out from there. Take a first signal, the dry signal, to an output.
The second output would be the delay signal.
I think for BBD devices, you should really filter pre and post. So I would pass the second output through an low pass filter, to the bbd, then another low pass filter to remove clock noise, then buffer the delayed signal to the second output.
I think someone above suggested you try the small clone as an example for using a bbd. I think this would work well with a few modifications. Using the Small Clone as a starting point, I think you can simply eliminate the mixer, and optionally the modulation section and you would have a pretty good start. (although I might leave the modulation section in and tweak it for a slower and more subtle sweep of the delay time - that may be cool.)
If you get rid off the modulation, I think you can get rid of the oscillator circuit based on the 358 op-amp and corresponding components up to the point where the diode and capacitor connect on the CD 4047, i.e., from the 39k on. Replace the diode with a series resistor and a pot for manual control of the delay time. Now, your delay can be manually set by the combination of the series fixed resistor and pot, and the timing capacitor.
Also, I would consider replacing the low pass filter on the output of the delay chip with a higher order filter. I have cranked a small clone into slap back delay range, and when I have done so, I got audible noise and clock bleed. At 25ms, you may likely be fine with the Small Clone circuit as is. If you want much higher delay however, I'd seriously consider a better post delay filter.
As I noted above, I am quite a beginner at this, so I hope someone else chimes in here.
I would be interested to know how it turns out.
I drew up a schematic based on Colin's suggestions, if you hang on a sec I'll draw it on paint and post it at my site. Hold on a sec... :?
Ah, I think an input buffer WOULD be a really good idea.
-Colin
I added an input buffer before splitting the signals ;) Hold on just finishing up...
OK check it out: www.geocities.com/smoguzbenjamin/stereo.html
That should work right?
Don't forget output caps and 2.2 meg resistors to ground.
Make sure you're giving the op amps 4.5v at the + input instead of ground if you're going to use a single supply.
I'm not sure if the lowpass will work, I'll have to spend a bit of time staring at it.
You didn't lable the +9v pin on the MN3102 (should be 1).
Same with the MN3207, should be pin 5.
The end of the pot should go to pin 7, not before the cap, I believe.
-Colin
QuotePin 7 connected to the end of a 22pf capacitor connected to pin 5
Pin 6 connected to the end of a 5k resistor connected to a 10k pot connected to pin 5
The schematic was drawn according to that ;)
The power amp stages have 0.1uF input caps. Putting two caps in series didn't sound like a good idea so I omitted the output caps here. 2M2 resistors to ground, whoops forgot about that :lol: I'll edit the schemmo.
The active filter, I calculated the values, the lowest passing freq is 15Hz and the highest would be 10kHz with the cap being 1600 pF, but since that ain't a standard value I decided to use 3 470pF caps in series. That's a total of 1410 pF. Close enough, if the clock noise still gets through I'll have to tweak it a bit.
Quote from: smoguzbenjaminQuotePin 7 connected to the end of a 22pf capacitor connected to pin 5
Pin 6 connected to the end of a 5k resistor connected to a 10k pot connected to pin 5
The schematic was drawn according to that ;)
The power amp stages have 0.1uF input caps. Putting two caps in series didn't sound like a good idea so I omitted the output caps here. 2M2 resistors to ground, whoops forgot about that :lol: I'll edit the schemmo.
The active filter, I calculated the values, the lowest passing freq is 15Hz and the highest would be 10kHz with the cap being 1600 pF, but since that ain't a standard value I decided to use 3 470pF caps in series. That's a total of 1410 pF. Close enough, if the clock noise still gets through I'll have to tweak it a bit.
The caps wouldn't be in series. The 3x470 is inside the feedback loop, a capacitor outside of the feedback loop won't effect it.
You're using a bandpass filter, then? That's quite interesting, I would have chosen a lowpass at about 8khz.
Try this circuit:
Active Low-Pass Filter
+---------+--------+
| | |
R2 C2 |
| | |\ |
IN--R1--+---R3----+---|-\ |
| | >-+--- OUT
| +---|+/
C1 | |/
| |
-------+---------+--------------
R1= 13 ohms
R2= 14 Kohms
R3= 13 ohms
C1= 2042 nF
C2= 1 nF
I got that from http://www.vwlowen.demon.co.uk/java/audio.htm
I think I described it wrong. It should be "A 22pf capacitor connected to pin 5 and pin 7. A 5k resistor and a 10k in series connected from pin 6 to pin 7". Look at the datasheet on my site, that should clear things up.
-Colin
P.S.-thanks for the credit! :)[/code]
Thanks for the help! Credit where credit is due in my opinion :) I edited the pin numbers for the MN3201, they're correct now I hope :) Now to de-lazyfy myself and re-draw that low pass filter :lol:
I was referring to the output caps of this circuit interacting with the input caps of the power amp stage, since each power amp has got a 0.1uF cap at its input before anything else, I decided to leave output caps out here.
Quote from: smoguzbenjaminThanks for the help! Credit where credit is due in my opinion :) I edited the pin numbers for the MN3201, they're correct now I hope :) Now to de-lazyfy myself and re-draw that low pass filter :lol:
I was referring to the output caps of this circuit interacting with the input caps of the power amp stage, since each power amp has got a 0.1uF cap at its input before anything else, I decided to leave output caps out here.
Ah, I've never heard of that. You learn something new every day!
Let me know how it turns out. The schem is a nice building block for a chorus/flanger with the addition of an LFO to modulate that pot.
-Colin
:) Right! Now to absolutely finalize the plans for the preamp, get the parts I need and build. Thing is I have an important school week from the 8th till the 12th march and after that I'm in London for a week. Damn.
Oh well. I'll amuse meself in the meantime :mrgreen: lol
Quote from: smoguzbenjamin:) Right! Now to absolutely finalize the plans for the preamp, get the parts I need and build. Thing is I have an important school week from the 8th till the 12th march and after that I'm in London for a week. Damn.
Oh well. I'll amuse meself in the meantime :mrgreen: lol
Waiting for parts sucks so much. I've been waiting for 2 weeks for this big order from futurlec, a few days for some sample orders (3 or so) and a while for an order from Smallbear.
-Colin
My TI samples shipped pretty fast :) 3 days or so to Holland. I'm not gonna start this next week though since I'll be occupied for the coming 2 weeks. Dang life has a way of kicking you in the ass and occupying you when you just get ready to start something relatively big! :x Drat.
Oh well I'll just hang out here and survive for a week or two :D