JH Living Vocoder [BUILD THREAD]

[OrganFixer]

I think jhulk is over there as he quotes things in pence. I think USA was a response to my question.

Regarding the resistor. Is there a
schematic to check against?

[jhulk]

lektroid im in uk

as for the resistor on the other forum all the problems was talked about maybe that info is there but would have to sift through a load of pages to find out

but like you i find the schematics are usually right

[jhulk]

The Living Vocoder is working.
As a summary, I suggest:

Synthesis Input and Compander
Levels:
R2610 (Potentiometer on front panel)
R2612=39K (to add 6dB of extra gain)
R2659 (Switch ExcMode and S_Mode OFF and Ns_Mode ON and adjust the trimmer R2659 for 1.23VRMS at U2606B output. Pin 7) (R2659 could also be on the front panel)
R2645=20K
R2649=7.5K
R2654=10K*
R2655=1.8K*
C2626=47nF*
R2657=20K
R2656=JUMPER
*PCB's Layout says 100K, 18K and 4n7 respectively. Schematics say the suggested values.

Switches:
C2622=100n
C2623=100n
C2624=100n
(These values attenuate “pops” when switching, these are noticeable when unvoiced signal turns on Ns_mode Switch for example.)

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Voiced/Unvoiced Detector
Filter's Cutoff Frequency:
I placed high-pass filter cutoff at 5000Hz and low-pass filter cutoff at 2000Hz.
R2311=33K
R2312=150K
R2309=56K
R2310=24K

Instability Preamp Protection:
Noise or high frequency oscillations in the preamp section will turn ON the unvoiced section.
To achieve protection to this, I considered to use the channel 17 analysis output instead of the high pass-filter, or convert the high-pass filter in a band-pass filter. However I found a more easy solution:
Place a 470pF capacitor in parallel with R2302 and
R2303=JUMPER

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Speech Input Amplifier
I noticed instabilities in this section.

TONE Network:
U2102A's inverting input has long trace and also it is the center leg of the TONE potentiometer. It will be recommendable take special care of this when assembling the Vocoder to the front panel, like to use a short length and coaxial cable (shell grounded).

A tested and working solution is to place a 100pF capacitor parallel to R2120.

An extreme solution could be bypass the tone section. In this case: do not place all components related (Blue labels on the attached picture) and C2111=JUMPER, R2117=20K, TONE 5 pin connector (pin 2 to 3)=JUMPER, R2120=20K with a paralleled 220pF capacitor. This is by now untested.

Preamplifier:
I'm using the chip THAT1510 instead the SSM2019.
My suggested values are R2101=10R, R2102=10R, R2103=1K, R2104=1K, RG0=OPEN, RG1=5R, RG2=Capacitor Electrolytic 10V 3300uF (will cut about 10Hz).

Limiter:
RLIM =6K
RG3=22K

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this is what was recommended for tuning the pcb
and some one asked about the values for resistors on the pcb values if they were correct and the answer was yes apart from the tuning values above

[jhulk]

the last was taken from the original 10 peoples thread

[LektroiD]

lektroid im in uk

Thanks, that makes things cheaper for me. Definitely count me in. Can I ask for 150 of each value though, as I always like to carry a few spares...

as for the resistor on the other forum all the problems was talked about maybe that info is there but would have to sift through a load of pages to find out

but like you i find the schematics are usually right

I saw Sound's reply on there, but the 47k/1k8 issue is not mentioned. It was also noted by Jürgen himself that there was another error on the schematic which was corrected on the PCB. I just don't know which way to turn in this instance...

I guess I'll leave it out for now, until I have completed the build, then swap them out and see which works best (unless anyone here knows better).

[jhulk]

put socket pins in easier for swapping on that value

[tjs]

I'd be in for a cap buy, 150 of each value.
Thank you.

[LektroiD]

Anyone thinking of drawing up a wiring diagram for this? I know there are many possible wiring options, so it would be good to see a few examples from various builders.

jhulk, I plan to put sockets in a few places.

[Synthsense]

My board was confirmed, so I'd like to be in the Caps buy too, 150 of each to make it rounder is fine for me. Europe

[consumer]

R2654=10K*
R2655=1.8K*

Further along in those posts others warn they had to revert to the 100k/18k values because levels were too high. Sockets.

There's a lot of good information in the e-m threads... wish they had an 'all' pages button.

[jhulk]

my pcb turned up today

are people using the 13600 or 13700

as in his docks on some of his builds he requests 13600 as he tried 13700 and did not work as good as the 13600

[jhulk]

consumer it was just a copy and paste from em forum build post i havent even started building yet i only got it at 1pm today

[synthdude]

Where are these pcb's available? I have built three different JH pcb's that I got directly from him back in the day and they are pretty much amazing. He was a genius.

[LektroiD]

my pcb turned up today

are people using the 13600 or 13700

as in his docks on some of his builds he requests 13600 as he tried 13700 and did not work as good as the 13600

I have read the 13700 can be used as a drop in for the 13600, but the 13600 is not forward compatible if the circuit utilises the additional diodes of the 13700.

I always use 13700 in place of the obsolete 13600 and never found any problems. I'll be using 13700's in mine (socketed). In fact for the money, it's probably a good idea to source 20 of each and swap them out, you'll always use them anyway.

[LektroiD]

Where are these pcb's available? I have built three different JH pcb's that I got directly from him back in the day and they are pretty much amazing. He was a genius.

http://randomsource.net/haible/vintage

There's a few original Haible PCBs in stock.

[jhulk]

if you ask him nice there is 1 string filter left

im getting a bunch of 13600 and i already have loads of 13700

im going to put socket pins in all those points that will need changing for the resistors

[synthdude]

Where are these pcb's available? I have built three different JH pcb's that I got directly from him back in the day and they are pretty much amazing. He was a genius.

http://randomsource.net/haible/vintage

There's a few original Haible PCBs in stock.

Cool thanks!

[LektroiD]

if you ask him nice there is 1 string filter left

You need to be specific when ordering, I ordered a string filter along with my vocoder board, he only sent one PCB (it needs two identical PCBs, populated differently to work). I had to make a separate order for the other. So make sure you specify 2 PCBs when ordering.

If he's sold out, it might be worth asking if he is likely to do another run; he may have plans on making a RS version, or maybe he will rerun the original. Something to discuss with him...

[synthdude]

I sent an email to confirm there are some pcbs still available for the vocoder. If he does I will order one this weekend. I would like to be on the list for a 150 each cap order.

[jhulk]

yes string filter is 1 pcb you need 2 if you want to make a 40 band one i also did the same thing and then told every one on this site that the string and scanner pcbs were available

then he had loads of orders luckily i managed to get a second string filter pcb when i paid the rest for vocoder

[jhulk]

he did say to me he might do a string filter run if enough interest

[jhulk]

any more for the caps really would like to get 3000 of each or more if possible

what about any other parts

turned pin sockets buy them in the 1000,s makes them a lot cheaper

[thermionicjunky]

my pcb turned up today

are people using the 13600 or 13700

as in his docks on some of his builds he requests 13600 as he tried 13700 and did not work as good as the 13600

I have read the 13700 can be used as a drop in for the 13600, but the 13600 is not forward compatible if the circuit utilises the additional diodes of the 13700.

I always use 13700 in place of the obsolete 13600 and never found any problems. I'll be using 13700's in mine (socketed). In fact for the money, it's probably a good idea to source 20 of each and swap them out, you'll always use them anyway.

Jörgen Bergfors claims that the 13700 has a bit less gain. Perhaps that is a contributing factor.

[LektroiD]

any more for the caps really would like to get 3000 of each or more if possible

I've just posted about the group buy in the vocoder thread in the SDIY forum on Facebook. Hopefully a few more might be in for them.

How many more people do you need in for the group buy?

what about any other parts

turned pin sockets buy them in the 1000,s makes them a lot cheaper

I usually pull apart some turned IC sockets for this. Any difference buying them individually?

[jhulk]

i only use the gold over bronze turned pin sockets for all chips i find the chip insertion types start to go black over time

done a few memorymoog rebuilds most of the time its those tin plate sockets and headers that go black that make them so hard to tune by changing to turned pin sockets and gold headers and they stay in tune so i make it a matter of course to use the gold types

i never understood why people buy expensive parts then skimp on sockets and cheap ass pots or sliders

if you want something to last do it right and only once

and why i wont buy parts from tayda if you buy in large quantities from mouser or farnell you can get them just as cheap and they usually are not b stock

for the turned pins as inline rows you can get them in 40 row and they have proper cut marks already so they are easy to snip unlike sockets