Where to get drivers for talkboxes?

[joelap]

Anyone know where to get a suitable driver for a talkbox, similar to the one used in the heil maybe?  I'm not sure where to look for one

[aron]

I remember cutting up plastic horn drivers..... I don't know where I got them from. Radio Shack?

[petemoore]

  You'll probably want some power handling...15+ watts, not more than 30 or your fillings or teeth fall out I hear...
  Distortion, eq, helps, most of the TB records are w/dist.
  Starting with a horn that can handle some lower frequencies and power.. 
  When I did that, cut up plastic and other types of horns, I was using an active Xover to range the freq's and attenuate, and did alot of trying to get wider freq response/volume/gain...deciding a more substantial driver would probably provide more of that.
  Also, thinking about the hose mounting is a good idea when choosing a driver, a wider diaphram/outlet probably has less pronounced diffraction [it may be tricky to get the driver/hose transition down to a smooth tube] than a smaller one with higher air speeds.
  I thought about a flat-flange type of driver mount, using a block of wood, making a hole the exact size of the driver outlet 1/2 way through, then a larger hole from the other side [by the amount of the tube wall thickness x 2] meeting in the middle of the block, hopefully ending up with a smooth walled tube/driver transition. 
  I don't know but suspect that horns driven at lower volume levels can withstand lower frequencies and sound good doing them, over-excursion is to be avoided, perhaps if you have available...more than one driver, a multi driver Y tube [2 drivers] could somehow be made.
  I have 6 'extra' medium sized console stereo horns, all look about the same, some say motorola..I thought about making a '6-cylinder' radial horn porting block so all 6 could gang up on 1 horn lens...never got around to it though, I haven't tested them with a good xover, perhaps they're kinda cool, the lenses are metal.

[mdh]

Since no one has mentioned a particular vendor, I'll mention that I bought a horn driver for a talkbox from Parts Express (http://www.partsexpress.com/). I just bought the cheapest one they had, and it definitely worked... of course I destroyed it in the end, and I'm not sure how. That was a couple years ago, during my baptism of fire into DIY effects (literally... I let the magic blue smoke out of a chip amp at one point). I've been meaning to get back to talkboxes, but I've been having too much fun with distortions, phasers and envelope filters

[remmelt]

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=260-097
Something like that?

[birt]

i prefer paging horn drivers instead of high frequency horn drivers. you get more mids.

i'm still looking for a reliable source in europe myself. if i can find them they are rdiculously expensive so i've been using olde paging horns from flea markets.

[remmelt]

Great idea.. Off to the flea market.

[joelap]

Thanks for the replies.

At the moment, I'm working on a design that works like the rocktron banshee, but doesn't require an external P/A, so the talkbox works like a regular pedal (you can feed the mic return back into the pedal).  The preamp or distortion circuit will distort the sound, and then I found a 5W poweramp IC at gigikey (TDA7056A) tht I planned on using to power the driver.  If 5W isn't enough, I'd find a higher one, but I figure if I use a sufficient driver it shouldn't be too bad.  Then, the return from the mic will be sent into a mosfet stage based off of Tim Escobedo's Duende, the purpose of that to compensate for any volume loss between the normal guitar output and the mic output, or even boost the signal a bit if needed for solos.  I'm meeting with one of my EE professors today for a little help reading the data sheet (the sample schematic shows a few parts I dont think will be necessary coming off of my distortion circuit).  My only concern is finding a driver that will be cheap, that can extend into the lower frequencies, maybe about 150Hz or so.  I know a lot of those drivers don't go that low, and I don't want to 1) run the risk of blowing the driver or 2) have to add a filter to filter out those low frequencies.

That direct link to the $10 parts express horn seems like a good starting point, though its range starts at about 600Hz.  Would I need to filter out the bass frequencies prior to the poweramp to protect the driver?  I'd rather not, sicne the tonestack I added is based of the BMPi tonestack, so it has plenty of bass on the duncan amps curve.

[mdh]

That direct link to the $10 parts express horn seems like a good starting point, though its range starts at about 600Hz.  Would I need to filter out the bass frequencies prior to the poweramp to protect the driver?  I'd rather not, sicne the tonestack I added is based of the BMPi tonestack, so it has plenty of bass on the duncan amps curve.

Can't you just use a passive crossover, i.e., a cap, between the power amp and the driver?

[joelap]

Can't you just use a passive crossover, i.e., a cap, between the power amp and the driver?

I don't know how to do that.  After looking at parts express, it seems the 600Hz one will probably be the best for the job, since the others dont get much better without getting much more expensive.  How can I filter out frequencies below 600Hz in that passive crossover method?

EDIT: found this: http://www.bcae1.com/passxovr.htm  reading into it right now.  Thanks for the heads up!

[mdh]

Take a look at http://www.the12volt.com/caraudio/crosscalc.asp. I used about a 20uF cap for a 6dB per octave high pass filter @ 1kHz. Then again, I did damage my driver (that same one on Parts Express), but I can't be sure why. Maybe I should have been more conservative (smaller cap), or maybe the damage didn't have anything to do with the crossover. Perhaps this doesn't inspire confidence, though 

[joelap]

hehe... here's some Cadence curves I just drew up for different values.  I used an input of 1VAC to represent the signal, and used a bunch of different cap values.  I guess by this graph, I should go for the 22uf or 33uf cap.



Actually, after reading your post, maybe I should go lower and try 10uf, although trying that website you sent me said for an 8 ohm speaker and a crossover point at 600Hz, I should use 33uf.  hmmm.  I guess 22uf will be a safe medium?


EDIT: For a -12dB per Octave filter, all I'd need to do is use a 22uf cap in series with the resistor and a 3mH inductor in parallel.  Not too hard, and 1mH inductors are easy to come by.  I think I might do that, so the rolloff is steeper for the bassier notes.  This should serve as a good protection for the driver from those lower frequencies.

[dr]

.....try MCM  www.mcminone.com ....part number:53-810; 1-3 items-$2.39 ea.;4-24 items-$2.26 ea.;25 and up items-$1.95 ea.....they are 2khz-20khz freq.response, and can handle 75-150watts....I have used them to replace the horn drivers in my old Peavey SP1's-they are good for talkboxes!........dr 

[petemoore]

  Would I need to filter out the bass frequencies prior to the poweramp to protect the driver?
  What you want need is subjective.
  that 10 bukk job looks like what I'd go for, 600hz is nice and low.
  How steep the frequency rolloff is is a big part of the equation...how low can you go with frequency / up with volume without blowing the diaphram.
  I'm not that good with figures, but 6db rolloff angle means you'll want the frequencies to start rolling off well above 600hz to keep the driver protected from seeing lower freq's.
  I built a simple HP Xover [it's on ESP pages, linkowitz-riley...just the top OA's IIRC for HP section], and stuck in 3n3 caps, not measured to be matched, worked pretty good...I didn't get around to building a wheatstone bridge comparator...and you'd have to tweek values to get the Xover point to move.
  I would say just a passive Xover...ask at Parts Express tech support for coil and cap values...something like 600hz or 800hz rolloff point with your 8ohm driver.
  I would guess rolling off some highs would be as simple as a treble control pot/cap...having that adjustabe might prove useful, some highs will get eaten during the transition through the tube/mic/line/amp/speakers etc., you could adjust them after also..
  PA...seems like that'd be a whole nuther trick getting a guitar amp to talk box...I would guess you'd want a clean amp, with a distorter before then TB driver amp.
 

[MKB]

Here's another one from MCM: http://www.mcminone.com/product.asp?catalog%5Fname=MCMProducts&category%5Fname=3829617&product%5Fid=54%2D050

Response is 100Hz-8kHz (the 100Hz is not a typo), 40W power handling, and only $18 each.  I have a pair of these and they look perfect for talk boxes, especially with the lower frequency response.  Only problem is that they are a bit large.  I've been planning to make a talk box out of one but haven't had a chance to do so yet. 

[joelap]

Pete, thanks for the response.

I guess I'll star the rolloff somewhere around 700-800Hz or so, and use a second order crossover with an inductor in parallel with the speaker (and the whole thing in series with the cap), so it'll have a steeper rolloff for lower frequencies.  Also, since it is only 10 dollars, I can take a risk blowing it, since 10 bucks is, well, 10 bucks and not 30-50 bucks or so.  And as far as talkbox into guitar amp, yes the amp should be set clean, and I have a distortion circuit rigged up which comes before the poweramp section which drives the driver. 

So basically, the only things I need now to complete the design on paper is 1) an enclosure, 2) a suitable tube-type and diameter and 2) a suitable connector to attach the tube to over the driver (or does the tube connect directly on that opening on this driver: http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=260-097 ?)

Thanks a lot for all the recommendations.

[joelap]

Also, do any of you guys know how to find something specific in the mouser catalog?  I'm looking for something, you know on the dunlop revision E wah board, how all offboard wires are connected on that single solderless connector?  The prongs stick upward and the solderless connector slides right on top?  I can't find those on mouser, probably because I dont know the technical name for them.  If anyone could link me to a listing of them, or assist in my finding them, I'd appreciate it.

[Meanderthal]

 If you can get ahold of the old school outdoor PA speakers for permanent/semi permanent installations, or the old military surplus version(you know, the kind with the metal horn that sound all nasal and lo-fi), unscrew the horn, and the driver is ideal for a talkbox! They're usually capable of handling quite a bit o power too...

[QSQCaito]

I'm trying to look for it, in spanish. Driver is something between a tweeter and a woofer, for mids??

Something between 1.5kHz and 20kHz??

Like this one:

http://www.deremate.com.ar/accdb/viewItem.asp?IDI=15156716
http://www.deremate.com.ar/accdb/viewItem.asp?IDI=15309623

others:
Input (rated): 35W
Impedance: 16£[
Frequency response: 150Hz~6KHz


It was what I understood for Horn Driver, sory if it's wrong

[Rodgre]

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=260-097
Something like that?

I've gone through two of these very drivers. The first time I assumed it was my fault, so I called Parts Express to order a new one, and they suggested that I needed to put a cap on it to protect it from low frequencies, so I ordered that as well.

It lasted about an hour and that horn blew too.

I was using a Vox Pathfinder 15 as an amp for it, and really didn't have the volume up high enough to do damage as far as I know. I needed it for one song at one gig, so at least I got through that...

Roger