DB54 - 2254 style compressor {update 22.10.19}

[MoJo]

I knew it Ian. We have an English daughter-in-law and have visited England many times. I should have noticed!

Baccatchya.
Joe

 

[MoJo]

Hi Everyone,

If I have 10VDC going into the sidechain transformer, but only 0.003VDC coming out of it, does that mean it probably is wired wrong?

 

[JMan]

It might or might not indicate a problem. Do you know if the transformer is gapped?

Which model transformer did you go with, and can you give a diagram or description of how you have it wired?

 

[MoJo]

Hi JMan, It is a Sowter 9145



And if is wired as follows:

Primary Blue wire (5 on the designers wiring diagram) to 5 on the PCB
Primary Yellow wire (2 on the designers wiring diagram) to 2 on the PCB

Secondary Red wire (7 on the designers wiring diagram) to 7 on the PCB

This is where it gets weird to me:

Secondary Orange wire (10) AND Black ground wire from the transformer soldered to the wire shield, then the other end of the shield wire is soldered to 10 on the PCB.

If I was to try something out, I would solder the Orange wire to 10 on the PCB and solder the black transformer ground wire to the shield, and solder the other end of the shield to the SH on the PCB.

What do you think?

 

[MoJo]

Hi JMan, It is a Sowter 9145

View attachment 146734

And if is wired as follows:

Primary Blue wire (5 on the designers wiring diagram) to 5 on the PCB
Primary Yellow wire (2 on the designers wiring diagram) to 2 on the PCB

Secondary Red wire (7 on the designers wiring diagram) to 7 on the PCB

This is where it gets weird to me:

Secondary Orange wire (10) AND Black ground wire from the transformer soldered to the wire shield, then the other end of the shield wire is soldered to 10 on the PCB.

If I was to try something out, I would solder the Orange wire to 10 on the PCB and solder the black transformer ground wire to the shield, and solder the other end of the shield to the SH on the PCB.

What do you think?

I checked my email from Sowter and they said the black wire is the screen connection. I don't really know what this means, but I assumed they meant ground.

 

[Rob Flinn]

Be careful with your BC214. There are a few different pin outs for them. It's not as straightforward as with the BC184. I had problems with this many years ago when I was building a Neve style compressor limiter.

 

[Mach 43]

Hello!

This thread about DB54 diode bridge compressor.
It's based around Neve 2254 but not a blind clone.

It's available as diy kits for those who are interesting in building their own compressor:
kit contain BA185, BA191, BA283 boards, board for joining BA cards, face board for switches and 24V psu board.

More info:
https://www.diystudiotoys.com

Some additional info here:
http://wiki.diyrecordingequipment.com/projects/garash-db54-diode-bridge-compressor/

Build info here:
http://bit.ly/2dLli43

Progress:
12.06.16 - topic start
21.09.16 - first run, check Reply #41 for video!
05.10.16 - fully calibrated and works as it should, check Reply #48 for more info.
10.11.16 - samples added! Check reply#71 and #73
25.03.17 - assemble gude added. Check reply#126 and further
12.10.18 - 9 kits left from third batch
22.10.19 - we start to order 4th batch of DB54




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PRIMORDIAL THREAD:

As a couple years ago I was really inspired by original 2254, I've started to explore its schematic and construction. Now, after about 8 month of lazy processing I've got some results that I hope very soon will be materialises in to the real piece of gear!

During my explore I’ve decided to get best from vintage, save mojo approach as possible, extract some not useful function and add some additional options multiplied by modern approach.

And here is what I’ve got:
- first of all I’ve recreated original BA cards - 185, 191 and 283, I hope that save some vintage “mojo”. Using same 18pin connectors give possibilities of using vintage cards that sometimes can be found on evilbay.
- one mono unit will feat into 1U
- limiter function was deleated, compressor only
- all wires between BA cards was replaced with pcb
- additional variable attack times (original has fixed on 5mS)
- additional faster release times
- meter off switch. Yeah, that's my own freaking function. It stay compressor in action but turn off the gain reduction meter. It let me concentrate on the sound and hearing it with ears not eyes))
- relay bypass

Unit will need three transformers (31267, 10468, 1166), three BA cards - 185, 191 and 283 and outboard power supply.

Your meter delete function is brilliant. I'm a touring FOH guy (30 years now) and my current go to gripe is how much modern digital audio consoles compromise your decision making simply due to everything being visually represented in front of you. It's impossible to ignore and in most cases, turning them off is not an option so, I do my best to not look or even, if I can, make adjustments with my eyes closed. The screens really do detract from your ability to listen. So, well done sir, well done!