New buchla 208 card 12,demo sound diy or built pcb no MB mods

[captnapalm]

One mod is needed to get the right main output working. There’s nothing feeding the input of the op amp. The original card 12 had a bridge between pins 7 & 9 so the same signal gets sent to both inputs, and is the same on both outputs.



On the Boops card if you want behavior like the original you can bridge them the same with a small wire or resistor leg:



If you want the behavior like Boops describes, you can take the output from the wiper on channel B pot:



Other options are possible if you want to experiment. I tried sending the CO output directly in before the gates, but it gave a lot of bleed so I abandoned that approach.

[captnapalm]

I did some comparison recordings between an original card 12 and the Boops. These aren’t a perfect 1:1 comparison because they were made many days apart and I recreated the patches for the Boops versions, but hopefully they’re helpful. All were recorded directly into Protools with an Mbox and no additional effects or plugins used. I tried to capture a variety of types of sounds so you could see how the reverb affected them etc.

Overall I find the Boops card is slightly tighter with cleaner bass response on the main outputs, but the big difference is in the reverb and the quality of the headphone amp, which are significant and much nicer to my ears.

I tried the motherboard mods Boops describes, but it gave less reverb response for me (but with finer grained control). I decided I like to be able to drown the signal in reverb so I went back to the original configuration.


Sample 1, original card
Sample 1, Boops card

Sample 2, original card
Sample 2, Boops card

Sample 3, original card
Sample 3, Boops card

Sample 4, original card
Sample 4, Boops card

Sample 5, original card
Sample 5, Boops card

[boops]

Many thanks Captain !

[boops]

Monsieur davebr page at Modularsynthesis

https://modularsynthesis.com/roman/boop ... card12.htm


Many thanks

[boops]

I order a new batch now,pm if interested

[boops]

A reverb mix level CV circuit (vactrol based) is ready to test,more in a few days

[boops]

I ve just finished to built a little pcb for the function :
CV control of the pot reverb ( VCA)
the reverb on the demo is this of my new card 12,but works with the original too.
I use (thanks papz for the idea) the rightmost pressure banana .
If interested by a pcb diy or or a ready built ,pm me
New really interesting modulations possible
a quick demo
https://soundcloud.com/boops95/new-card ... t-mix-demo

[boops]

the new pcb batch will be available in a few days


pcb card 12 is 40 eu +reverb cv 15 eu + bracket
shipping is 10 eu bubble letter registered WW

built card 12 :130 eu +reverb cv 35 eu little package registered shipping Eu cheaper or WW

[boops]

Available.

[boops]

Order before the summer vacation;)

[boops]

last days before vacation Rockin' Banana!

[keithwin]

One for me please!

[boops]

in stock but
i will come back home not before 6 weeks...

[boops]

Available ,in stock.

[captnapalm]

BOM has been updated with all in-stock components and best fitting caps

[boops]

BOM has been updated with all in-stock components and best fitting caps

Thanks

[Clemdu]

Hello everyone,

I'm finally getting around to build this card

any word on the motherboard mod? I read Captainnapalm prefered the original, any other experiences out there?

Thanks!

Clem

[boops]

Finally ,i didnt keep the mod,i use a resistor like DaveB
see his web site notes

[boops]

A few pcb in stock .

[boops]

up

[PacificState]

With a bit of advice of Dave Brown along the way (thank-you again, if you read this!), I have my 208 working with the new card 12. I'm about to calibrate it, but I'm noticing that I'm getting MO + CO bleed into the headphone output if I turn both outputs + the reverb mix down. The signal output jacks, on the other hand, seem to be totally clean.

Given the previous comments in the thread, I'm not sure I would expect this. Any ideas? I've cleaned flux from the board and checked my soldering - I guess it could be a grounding issue? Thanks!

[klangbauer]

Is there a complete CARD 12 schematic around??

Because it is DIY and I hope I get one for better understanding what I'm doing and necessary for debugging.

As far I understand from the partial schematic here, a LME49740 works as a part of reverb recovery amp. It boost a tiny signal from reverb out x20 and therefore it is sensitive for noise. Therefore to replace it with an TL074 is not best choice. As far I understand.
I my design I use at this point a NE5532, but it is only a dual opamp.
A complete schematic could help for a better understanding.

[boops]

Did you buy a pcb?
Do you have an issue?i can help.
All the infos in the first page of this topic.

[boops]

part of the schematic since mars 2019

Someone ask me the schematic
unfortunaly, for private reasons,i can not share the complete schematic
for the moment.
But i can help ,if needed to debug and

https://modularsynthesis.com/roman/boop ... card12.htm

very interesting !!

do you have a schematic ?
thx

In the future sure ,diyers will need it.

edit
for private reasons,i can not share the complete schematic
for the moment.

[klangbauer]

I bought three Cards for a respectable price, and so I expected a schematic. Boops ignored several mails asking for schematic. So it is was a pain to build. This is not for a beginners project. Finally he told me, schematic is not for private customer! See his mail above.
He always promised a schematic and don't do it, but sells pcb.

It is DIY, so there must be a schematic, one BOM with available parts (no LME ...) and easy understanding build instructions.