IJR's 2254/33609!

[syn]

2254 calibration

It would be better to ask Igor, I haven't tested this yet. In the mean time have fun...

Did you use Igor's PCB layout?

greetz

 

[Rob Flinn]

Syn

Thanks for that. That was the kind of stuff I was looking for.

I am using Igors board layout, which may present some problems lining the thing up because it's not a 33609 or a 2254 really. I know there is a level change somewhere in the circuit to accommodate this.

 

[syn]

cool

bits and pcs of info...

http://www.auroraaudio.net/dcforum/DCForumID1/192.html
http://recforums.prosoundweb.com/index.php/t/13315/0/

 

[syn]

Rob

any progress? Hope you don't mind me asking...

Thanks

 

[Rob Flinn]

NOt really ! I spent some time a few weeks ago on one channel & got it passing a signal, but no compression is happening.

The calibration is very difficult because it is neither a 2254 or a 33609. I suspect that something is not happening in the side chain ! I could really do with some advice from Igor on how to calibrate this, but he doesn't seem to be about lately.

 

[Swedish Chef]

Did this just die again?
Shame. IK have a real one with both compressor sections not doing their thing.
The PT went open circuit so I replaced it and soak tested it before sending it back to the client, but he didn't try it for 3 weeks and now I have it back :-(
PS still solid but the comps ain't happy...

chef

 

[Rob Flinn]

Well I finally have my version of this project compressing & limiting, & it calibrated nicely. 

The one problem I do still have is some HF oscillation at extreme make up gain settings.    Igor did you have any problems like this ??

 

[Rob Flinn]

Nailed it !! The audio ground needed to be connected to chassis ground !!

Thanks for another great project Igor, even if it did take me 4 years to complete having sat on the shelf for months at a time while I was too busy to look at it   !!!

Am I the first/only person to have got this working ????    If so I don't feel quite so embarassed at the time it took !

 

[Igor]

Congrats!!! Happy to see this post. PICRTUREZZZZZ!!!!! There was one UK person who built this comp as well.

 

[kambo]

mine is on the way too
waiting for some parts

 

[kambo]

This compressor deserves good iron. It is the sound.
One guy ordered from me two of these comp's and we used
choke+ungapped out trafo, line in's old round ones, and by the reason
it was impossible to find any original mic inputs, I just re-wound same line in (to use same iron).
Choke + ungapped trunny sounds killer (in good sence) for drums, and compared to original 2254, there's same character of sound and compression.
Original by unknown reason sounded very tiny bit more distorted on highs.
Choke+ungapped gave very  "neevish" lows on drums/bass (we preferred this combination).

Hi Igor,

can you give us more info on this choke+ungapped  output transformer and also wiring/options ...
where to get them from...
can we get choke's from sowter, which ungapped tranformer did you use etc?

 

[Wonderlandaudio]

This compressor deserves good iron. It is the sound.
One guy ordered from me two of these comp's and we used
choke+ungapped out trafo, line in's old round ones, and by the reason
it was impossible to find any original mic inputs, I just re-wound same line in (to use same iron).
Choke + ungapped trunny sounds killer (in good sence) for drums, and compared to original 2254, there's same character of sound and compression.
Original by unknown reason sounded very tiny bit more distorted on highs.
Choke+ungapped gave very  "neevish" lows on drums/bass (we preferred this combination).

Hi Igor,

can you give us more info on this choke+ungapped  output transformer and also wiring/options ...
where to get them from...
can we get choke's from sowter, which ungapped tranformer did you use etc?

This is the original Marinair T1310 choke used by Neve when unbalanced output on the B283 or B183 was enough ( Usually in routing/ switching modules). Or sometimes in combination with the LO2567 output transformer like in the 1290.

I have lots in case you need any.

 

[kambo]

i sure am interested
i will email you...

 

[Rob Flinn]

This compressor sounds good with the gapped transformer too.  I have used Marinair & Carnhill transformers & it sounds great to me/

 

[kambo]

i used gapped carnhills on my 2254C they sound great too... i wanna try this choke+ungapped option on this version
i am getting close to finish...

Rob, i read some members have some un-compression issue... is this due wiring on top layer ?
do i need to be aware of anything...

 

[Rob Flinn]

Rob, i read some members have some un-compression issue... is this due wiring on top layer ?
do i need to be aware of anything...

I'm not really sure what you mean by this ?  Can you clarify ?

 

[kambo]

NOt really !   I spent some time a few weeks ago on one channel & got it passing a signal, but no compression is happening.  

The calibration is very difficult because it is neither a 2254 or a 33609.  I suspect that something is not happening in the side chain !    I could really do with some advice from Igor on how to calibrate this, but he doesn't seem to be about lately.

ohh it was actually you

was it your wiring/component  mistake or pcb mistake ?

 

[Rob Flinn]

Is was several mistakes, I can't remember exactly as this was several months ago, & I've had a lot on the bench since then.

However what I found useful was looking at the stereo link point & switching the comp/lim in & out, you should see a rising & falling voltage.  If this is not present you won't have any comp/lim action happening.  You can then look at the 2 sidechains to see where the signal disappears, 

You need to be more methodical than with the other 2 Neve type clones that igor has made, since the hook up is easy to mess up.  This isn't quite so much of a paint by numbers job like some projects round here

 

[kambo]

thank you Rob... makes sense...