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talkbox

Started by 12bar13, April 16, 2008, 10:02:04 PM

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12bar13

i want to try my hand at a making a talkbox. as far as i can see all it takes is basically making a small amp with a tube and a collector of some sort. this seems way to simple to me. is there any more to these things?

ACS

In fact, you don't really even need to make the amp - I run mine off a 15W Peavey Rage practise amp!

I built mine using the instructions at http://www.blamepro.com/talkboxG.htm, no problems at all.  I think the commercial ones have a protection cap in there somewhere as well, but it's certainly not necessary...


12bar13

did you have to cut up the amp or did you just strap on a tube?

ACS

Nope, I go:

Amp>speaker out>talkbox

If you have a read through the link above, you'll see that the talkbox takes the place of the speaker (it actually has a speaker / horn driver in it).  I then have a switch in the talkbox that sends the amplified signal to either this horn driver or to the original speaker - that means I can turn the talkbox on or off at the push of a button.

That's just one way of setting it up.  Other have a dedicated amp for the talk box, and just switch their guitar signal accordingly.  Remember that a talkbox by itself is next to useless - you need to have the tube strapped to a mic and then have *that* amplified or recorded to make it any use at all...


12bar13

you know i got an old crate practice amp collecting dust that i could use however it doesn't have an output.  could i just stick a switched jack in line with the existing speaker?  that way i don't have to lose the amp.

thanks
joe

ACS

Yep, my old Peavey didn't have an output either - my solution was to cut the speaker wires, wire in a phono plug on one side and a phono jack on the other - so then I could connect it back up to run as normal.  Otherwise I can disconnect the plug, put the talkbox in circuit and imitate Dave Gilmour perfectly...

Ok, all true but that last bit...

12bar13

seems simple enough.

thanks for the help
joe

ACS

Oh, one caveat: if you're going to do this with a tube amp, MAKE SURE YOU GET YOUR IMPEDANCES RIGHT!!!

(we don't like smelly transformer smoke, not one little bit...)


12bar13

transformer smoke is never a good sign

where is a good place to get the horn driver from?  i checked ebay and they all seem to be componants for high end speakers or way too big for what i need.

ACS

Ebay is probably the best bet.  I actually got mine from a second hand audio place - it was the driver from a high powered (100W I think??) "Tannoy".  Tannoy is actually a brand name, but it's become synonymous with the types of speakers used at sports fields etc.

Something like this http://cgi.ebay.com.au/NEW-TITAN-FOOTY-FIELD-WEATHERPROOF-60-WATT-HORN_W0QQitemZ220224339372QQihZ012QQcategoryZ23794QQssPageNameZWDVWQQrdZ1QQcmdZViewItem - this is Ebay Australia though!!  I paid $10 for mine, as the 'horn' itself was beaten within an inch of its life - however the driver was still fine...

Good luck!! By far my favourite effect, you'll love it!

Aidan

12bar13

once again thanks a lot for all your help. i just found this forum today and i have been browsing though it all night!  i love this place

joe

ACS

No problems mat e- it's nice to be able to answer someone's question, rather than being the question asker all the time  ;D

c101aviojet

I built one using a driver similar to this one: http://www.mcmelectronics.com/product/555-6426
There are many drivers available, and you can use one salvaged from an outdoor speaker, but if you want to build a top performing device I would buy a new horn driver.

I spent quite some time looking for a driver that would go as low as this one! Most start at 500-600Hz. Mine, starting at 150Hz (or so it says!), sounds like a mad growling beast!  :icon_mrgreen:
The tube adaptor will be hard to find; I finally called DUnlop and ordered the one used in the Heil talkbox (I'd say it was part #307, talkbox driver nut); it's a very well made machined aluminium nut and shoudl fit well the driver. Also, the tube size used in Heil's seems to be the better compromise betwee sound/usability.

As for the amp, I'd go with the cheapest solid state amp (=old practice amp) you have. A tube amp will hardly be any improvement sound-wise, so avoid them.

After some initial trials, I'm finishing mine. I built a plywood box and installed a 10W Academy amp inside (both amp and speaker). The amp is a bit on the short side, since all knobs have to be nearly pointing 11, but the driver can deafen you anyways. It measures about 25x27x20cm, If I recall correctly.
I'm wiring everything so as to have the following:
- With it's internal amp, you can put the talkbox in an effects chain just like any other pedal.
- However, you can also override the internal amp and plug it to an external amp.
- You can select to power the driver or the speaker, so the talkbox can still be used as a practice amp / microphone amplification system.

I'd totally encourage you to build one. If you like wahs, you'll enjoy this. It gives you an inmense amount of freedom and it's pure funk coming out of your mouth!
But you'll have to keep a small cloth around to avoid "drowning" the tube... :icon_wink:

Hope this helps! I'm searching for a funky fabric while I finish the build of the enclosure. I will post some pics when it's done!

Valoosj

I'd love to see the pics. Last year I bought the Dunlop, the thing is KILLER!
Only downside is that you end up drooling all over yourself :D Try not to do that in front of hot girls in any audience
Quote from: frequencycentral
You squeezed it into a 1590A - you insane fool!  :icon_mrgreen:
Quote from: Scruffie
Well this... this is just silly... this can't fit in a 1590B... can it? And you're not even using SMD you mad man!

Sir_Ian

I just built a talkbox a while back, and it was actually what got me into building pedals. I needed to make an a/b switch, and this forum and others had all the info.

Here's what I did. I bought a cheap 10 dollar horn driver from partsexpress. put it in a box, with a tube coming out, and simply put an input jack into it. The jack goes straight to the talkbox. If its plugged in and it gets a signal, then....its on.

I built a simple a/b swich with one input and two ouputs, and here is how I plan on running it.

Guitar to and and B switch.

A switch sends signal to regular big amp for playing music.

B switch sends signal to practice amp, which then sends it to talkbox. Talkbox is then picked up by mic.

Now my brother's practice amp has a line out, which will bypass his speaker and send the signal directly the talkbox after amplification. Mine, has no such thing. It has a headphone out, but that don't work well for this. Other people cut out there speaker and just put the talkbox in the amp. What I'm actually gonna do in the next week (i just got the parts in) is to mod my amp. I bought a enclosed input jack and a enclosed input plug. I'm going to cut the wires from the back of my practice amp to the speaker. I will solder the "jack" to the amp wires, and the "plug" to the speaker wires. And then just "plug" the speaker into the practice amp(i'm not moving the speaker at all, just leaving it in its location in the amp box). This will me to still use the practice amp. But If I turn off the amp and unplug the speaker I can plug in a speaker cable, and run the speaker cable from the amp to my talkbox. With my talkbox's Horn driver effectively taking the place of my amps speaker.

So my path will be. Guitar -> guitar cable -> a/b switch -> guitar cable -> practice amp -> speaker cable (like instument cable, but not, don't ask me what's the difference. I'm too ignorant). -> talkbox


But the sites linked above tell you exactly how to do it. But if you have any questions, feel free to post back in this topic. This forumn has answered so many of my questions, and now its my turn to help out on something I'm a lil' familiar with. I hope what I wrote was clear, but it might not be. You see, I'm writing this at 2:20 am in the morning....so yea... Anyway, good luck.

ONE LAST WARNING. I don't know if you have read this, but the reason you want to use a practice amp and not a nice fender hot rod deville or anything is because big amps are big and can blow the horn driver in the talkbox, which will inturn blow up your amp. With a practice amp, its a lot harder to screw anything up, and if you do, your only out 40 dollars, not hundreds. ok. bueno.
Time flies like an arrow, fruit flies like a banana.

c101aviojet

#15
Quote from: Valoosj on April 17, 2008, 05:19:14 AM
I'd love to see the pics. Last year I bought the Dunlop, the thing is KILLER!
Only downside is that you end up drooling all over yourself :D Try not to do that in front of hot girls in any audience
When I'm done with it, I'll open a post and I'll let you know. ;)
Regarding drooling... So true!  :icon_mrgreen: The firsts times, when you aren't used to it, it's even annoying. After a while, though, you can manage to keep it under reasonable limits. Depends a lot on the player too! Some play dry, others resemble a sweaty bulldog and there are even some who have their gag reflex triggered when playing!  :icon_lol:

Quote from: Sir_Ian on April 17, 2008, 05:25:07 AMONE LAST WARNING. I don't know if you have read this, but the reason you want to use a practice amp and not a nice fender hot rod deville or anything is because big amps are big and can blow the horn driver in the talkbox, which will inturn blow up your amp. With a practice amp, its a lot harder to screw anything up, and if you do, your only out 40 dollars, not hundreds. ok. bueno.
+1 to that.

- Some things to have in mind while making a talkbox:
- I must insist on Heil's nut. There just no better way to connect the tube to the driver. It's cheap (10-15$), it's very well made (machined aluminium, black anodized matt finish), it's the best design sound-wise and it's readily available.
- Always keep the throat of the driver closed while you manipulate it! Any dust or debris inside will cause major noise and possibly shorten dramatically it's life. You can use a small kid balloon, pvc tape, masking tape, etc. to do so.
- While playing, have a cloth nearby to keep everything dry. You can also put a hair band around the tube, a few cms from your mouth to help with that. Make sure it doesn't constrict the tube!
- I'd recommend to screw/unscrew the nut and driver several times, with a few drops of oil if you want, as hard as possible, to break-in the threads and make them adjust better. When it feels well, put some teflon tape on the driver, screw the nut as hard as you can and you'll have an life-long airtight seal.
- When a buddy sees the talkbox, he will unavoidably insist on trying it. My answer to that is letting him use it with a "courtesy tube", which avoids the somewhat disgusting act of sharing a plastic covered in saliva.  ;D
- Back to amps; what works best is a cheap, low-wattage solid state amp. A simple, reliable, mess-free amp. Something in the 10-30W range should be more than enough. As I said, a <10W amp will power a 60W driver strongly enough to harm your ears. An amp with more power probably distorts less, but remember the driver has a power rating! Always keep a safe margin and match impedances (the amp impedance must be equal or less than the driver's!) And save your tube amp for the solos!
- Use a filter (a cap) between amp and driver to kill unwanted freqs.  The formula to know it's value can be found here.





Mark Hammer

Talkboxes depend on confining the frequency content of the signal to your mouth and creating resonances via reshaping your mouth.  Since your mouth isn't that big, and the musculature only has so much flexibility, the resonances aren't going to cover a huge range.  They most certainly will not extend as low as some wahs do, although they can go higher. 

At the same time, the resonances created are perhaps not as "unidimensional" or "unimodal" as a wah.  Makes sense in several ways.  First, all speech contains multiple bands of energy or "formants", so you would expect the mouth to be "engineered" to affect sound passing through it in that way.  Of course it also makes sense that most electronic attempts to mimic speech-ey sound with a footswept pedal involve multiple filters that set up several different resonances.

Why am I telling you this?  Well, for one thing, the typical recommended use of a midrange horn driver and frequency-limiting cap is not only because of physical convenience (smaller, easier to couple to the tube, no driver burnout from bass, etc), but because the sounds you will primarily me modulating with your mouth ARE those midrange frequencies that are a normal part of speech sounds, and for which the resonant properties of your mouth were designed....by evolution.  Even IF the driver was comfortable with 200hz, unless you are Barry White (in which case you would be dead and unable to read this), your mouth could do very little, if anything at all, with that frequency content.  At the same time, because the resonant cavity properties extend higher than a wah, and because you tend to lose top end the longer and more absorbent the tube is, you will want to either keep the tube as short and direct as possible, add some top end via distortion, or both. 

Because less than the whole signal passes through your mouth, you may want to split the signal into bass and mids-and-up.  The bass gets amplified to be audible or perhaps mixed back in with the voice-modulated signal and then fed to an amp or PA.  There are two reasons why you want to do this.  One is that you'd like for the signal not to change from full to thin and reedy whenever you do the talkbox changeover.  The other is that losing the bass will lose a lot of signal level and turning up the talkbox mic level too high might get you more feedback than you'd like.  It's one thing if you're Peter Frampton on a huge stage where the speaker banks are a good 20 feet away, and quite another if you're gigging in a small bar.

12bar13

one thing that i have been thinking about doing is sticking a little switchable distortion (maybe bsiab) in there with a bypass and gain/level knobs just for a little tweakbablity. is there any reason this wouldn't work? as far a i can see all i have to to is cram one in the enclosure.  do you guys think that a fuzz might sound a little better?

thanks

GREEN FUZ

Check out the GHETTO TALKBOX on youtube. It will give you an idea of just how easy it is to build.
Or for a slightly different slant, the NOT SO GHETTO TALKBOX.
Or, the CHEAP option.

ACS

Quote from: 12bar13 on April 17, 2008, 01:46:57 PM
one thing that i have been thinking about doing is sticking a little switchable distortion (maybe bsiab) in there with a bypass and gain/level knobs just for a little tweakbablity. is there any reason this wouldn't work? as far a i can see all i have to to is cram one in the enclosure.  do you guys think that a fuzz might sound a little better?

thanks

As you're dealing with speaker level signals here, it wouldn't be possible to use a fuzz in that way.  Remember that while you talkbox can physically sit on your pedal board, it's actually not part of the signal chain down there... So you go guitar>effects (this is where you'd have to put your BSIAB)>amp>talkbox(>with a bypass option back to standard speakers if required).