DB54 - 2254 style compressor {update 22.10.19}

[jona]

i will try, thanks 

 

[Spencerleehorton]

My build is nearly perfect but I have some hum, I'm thinking it maybe due to my screens on my txf not being down to gnd?
Should they go to chassis gnd or audio gnd?
If they were not grounded would the circuit hum?

 

[vitopower]

I received my Garash db54 boards, shipped to USA, excellent communication, fast shipping w/tracking, expertly packed and with a few cool extras.

Thank you diystudiotoys!

 

[kml23956]

Can anyone get transformers for this? What are you using besides AML because their site is empty for these as far as I can tell right now.

 

[Spencerleehorton]

I've wound my own to original spec, the winding sheets are in the technical documents section

 

[lennieh]

Can anyone get transformers for this? What are you using besides AML because their site is empty for these as far as I can tell right now.

AML have them back in the online store now

 

[jona]

hi all,

need help with build.. rev 1.0.
i have the exact same problem as Zergonion had earlier in this thread.. using an external 24V psu
voltages are ok on all card connector-pins .. bias on ba283 is adjusted..2,3vdc.
unity gain calibration doesn't work..when i send 1vac to the input i have signal only when compress is switched off. when i switch it on, there is nothing but a very little distorted signal. almost like bleed from side chain or something...
meter is working ok and reflects parameter changes of the front panel controls..
i have made 2 of each BA boards.. i interchanged them but still the same issue
somehow i think it has to do with the wiring but i checked everything over and over..same as in assembling guide.. i am using Carnhill versions 9046/9045/1148..

would be great to get some help...

thank you

 

[SubhumanRecords]

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




----------------------------------------------------
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.

When will the full kit be available again?
Thanks

 

[Kid Squid]

Anyone interested in original style metalwork ?
I'm gonna be doing a few for myself in the original plugin style.

Best,
Steve

 

[JosephGaetanoPapa]

I am building the BA185 board and had a question concerning capacitors C1, C2, C3, and C4; the ones I ordered look like little boxes but the ones in the pictures are cylindrical shaped. I don't find any 330pf 100V polypropylene film capacitors on the Mouser website that are cylindrical. Will I be building a substandard unit by using the little box shaped ones? Or should I hunt for cylndar shaped ones?

Thanks for any help,
Joe

 

[scott2000]

the ones in the pictures

What pictures are you referring to?

 

[JosephGaetanoPapa]

What pictures are you referring to?

One of the pictures that the creator put on the https://garashlab.com/db54 website.

 

[scott2000]

One of the pictures that the creator put on the https://garashlab.com/db54 website.

I'm not familiar with this project or what capacitors you are referring to but, I did see some polystyrene caps in the pics. Are those what you are talking about? Not sure they would be available at Mouser or wherever...Maybe have to find NOS somewhere..
Polystyrene caps are said to sound sweet but are somewhat delicate and require extra care when soldering if you do go with them. No camping out on them with the heat.

 

[JosephGaetanoPapa]

Thanks for your reply Scott2020. Here are the pictures of what "they" used and what I have:


What I have



I can't find any online article that specifically identifies what each type of capacitory "looks" like, and I am not knowledgeable enough to know what I am looking at. What do the ones they look like to you?

Thanks for all of your help,
Joe

 

[JMan]

The ones in the upper picture are polystyrene, yours are (I believe you said) polypropylene. Realistically, both are excellent dielectrics for audio. You probably don't need to hunt down polystyrene caps if you don't feel like it, the ones you have will be great.

 

[Jim50hertz]

Those are polystyrene capacitors Joe. Although it’s not strictly necessary to use exactly the same type of cap it’s advisable to stick to the same types as used in the originals or as used by the kit provider. Banzai in the EU has polystyrene caps or do a search for Styroflex caps (a brand)

 

[JosephGaetanoPapa]

Thanks so much Scott2000, JMan and Jim50hertz; I want to stay as close to original design and build as possible, so I will hunt them down.

Best wishes,
Joe

 

[Brian Roth]

The polypropylene caps you have should be fine. But, if you "insist" <g>:

https://www.mouser.com/ProductDetail/Xicon/23PS133?qs=Txz0Knfx5nM0cPEt0WLgxQ==

The shipping will FAR exceed the parts cost. When I have that problem, I scratch my head and find additional parts I need (or might need) to ""pad" the order.

Order extras. Those caps are pretty fragile and will melt from soldering heat if you're not super careful.

Bri

 

[JosephGaetanoPapa]

The polypropylene caps you have should be fine. But, if you "insist" <g>:

https://www.mouser.com/ProductDetail/Xicon/23PS133?qs=Txz0Knfx5nM0cPEt0WLgxQ==

The shipping will FAR exceed the parts cost. When I have that problem, I scratch my head and find additional parts I need (or might need) to ""pad" the order.

Order extras. Those caps are pretty fragile and will melt from soldering heat if you're not super careful.

Bri

Thanks so much Brian. I found those also, but didn't get them because they are 50V (the build called for 100V). I was able to find them in 125V from Elliot Electronic Supply. I don't know enough about electronics and circuits to determine if 50V would work; additionally, there is no schematic available from the designer of this particular build (and he states that it is not an exact replica of the Neve unit)..

Thanks again Brian,
Joe

 

[Migs 31]

it is not an exact replica of the Neve unit)..

Exactly, you wrote "not an exact replica of the Neve unit"
So don't worry about the polystyrene versus the Kemet film capacitors you have, they will be fine.
Enjoy your build, have fun Joe.
M