Thomas Organ Wah inductors

[Mark Hammer]

I would imagine you might want to adjust one or more other component values to make something that large a value sound the way you want a wah to sound.  IIRC, though, I don't think I did too much tinkering with the critical range-setting cap, if any.  All my changes were to adjust the gain of the first transistor.

[Paul Marossy]

Thanks for the tip, Mark. 

[yeeshkul]

Guys this is a good article about tweekin V847 to V846.
http://www003.upp.so-net.ne.jp/kazuhee/ewahmod1R.htm

After reading that, i am much more relaxed about picking "the right"  inductor 
Also can you please tell what the frequency-response graphs show exactly? I have no idea what is the frequency on the X ax is (was he sweeping frequency of a testing signal to the wah while the treadle was fixed at a position or ...).

for Geoffrey Teese: man i checked the mp3 of your Picture Wah, that's a brilliant sound. Hat off.

[Dai H.]

it seems like he put the wahs at their extreme positions (max treble, max bass) to get the measurement. It says "sine sweep" on the graph, so maybe a sine wave that swept through the frequencies? To touch on what Mark said, the gain of the 1st transistor does seem to affect the wah range. I tried a 2N2925 which I liked, and when I later measured the gain on that plus some other ones I tried I found the 2925 to be something around 400.

[Paul Marossy]

the gain of the 1st transistor does seem to affect the wah range.

As well as the value of the resistor on the emmitter of Q1.

[Austin73]

Does anybody have a link or info on the TDK inductors .

I'm really struggling trying to get any info on inductor size so just wondered if you knew of a site or had a list of values.

Cheers

Aus

[Dai H.]

meaning you're having trouble reading the values on those inductors? If they have numbers like caps, then I think you can read them the same way, for ex. "154" = .15H = 150mH. Therefore, "504" = 500mH, "203" = 20mH,  and so on.

(1000mH = 1H)

[Austin73]

cheers for the info.

Looks like I've scored lucky then as they are all pretty much 500mH!

Yeah and I have about 60!

Aus

[Austin73]

Actually disregard my last post I had just got up off Nights!


That can't be right. I know when previous posts have come in most of the inductors are of a small 20mH range.

I had a quick look through the 'stash' I have and the numbers do not correspond.

Heres an example of the numbers.

TDK RED ONES as in the pic

382GB1
368GB1
439GB1
468GB1
512GB1
527GB1
582GB1

Black Ones Yamaha

527
539
456
518

etc the list goes on.

I am waiting to here from the mechanic at work if he has a multimeter with inductance as I don't , and I don't have a frequency generator to do it via the maths.

If I find out what they are I wiil post my findings but till then would still love any input.

Cheers as always

Aus

[Austin73]

Just thought I'd add to this one.

Got my new DMM checked the values of the inductors I have and DOH' was reading the things wrong 512 isn't 5.1mH its 1.2H so unlike caps the value of the power number is at the front.

Which means I have a 8.2H inductor now stick that in a wah and see what happens! .....................although I'm sure nothing will happen!

Check out the trade/sale board for the values I got out of it!

Aus

[CodeMonk]

Just wondering...
If anyone has wired up wah to use multiple inductors (via a switch of course).
Or is this not a doable idea?

[tehfunk]

totally doable.

[swt]

regarding the use of buffers...i read somewhere that Jimi used the tychobrahe octavia between the fuzz and wah, there are pictures you can trace, to see the wires going between pedals, and fact is that the octavia was not true bypass, and has a buffer always present in bypass mode. So there you have it!!, there is a buffer from wah output to fuzz input. I really don't like wahs with buffer inputs anyways...think the output buff is the way to go.

[zombiwoof]

One point - Hendrix didn't use a "tychobrahe" pedal, he used a custom Roger Mayer one, the Tychobrahe was copied from a "borrowed" Mayer pedal.  Mayer claims that the one that Tychobrahe copied was an inferior earlier version (he made several different ones for Jimi).

Al

[DavidRavenMoon]

Paul i am not writting them off at all. I'm  just surprised as i expected something with "Thomas Organ" on it instead haha. I am definitely gonna use them

Thomas Organ manufactured gear under the name "Vox" in the states, and that would include their version of the Vox wah, which was sold under the name "Cry Baby".   They invented the wah.

http://en.wikipedia.org/wiki/Wah-wah_pedal

From Wikipedia:

http://en.wikipedia.org/wiki/Vox_(musical_equipment)

In 1964 Tom Jennings, in order to raise capital for Jennings Musical Instrument's expansion, sold controlling interest in JMI to the Royston Group, a British holding company, and sold American rights to the California-based Thomas Organ Company.

One of my first amps was a Thomas Organ Vox Super Beatle.  The Thomas Organ Vox amps were all solid state.   

http://en.wikipedia.org/wiki/Thomas_Organ_Company

[Paul Marossy]

Thomas Organ manufactured gear under the name "Vox" in the states, and that would include their version of the Vox wah, which was sold under the name "Cry Baby".   They invented the wah

According to my research, and Maestro's claims, the Maestro Boomerang was technically the first wah pedal on the market. The patent it was manufactured under predates the patent that the McCoy and CryBaby wahs are manufactured under - it was filed in 1961, and the shell it used was filed in 1958. The Vox/CryBaby wah pedal that we all know and is featured at www.geofex.com didn't have the patent filed until 1967, IIRC. In any case, it appears that the Boomerang and the McCoy wahs hit the market very close to the same time.