PRR-176 REV 4 Build Thread ***Manual up!***1/16/14 - (chk 1st post)

[ilfungo]

Thanks berkleystudios
I also think something like this!

Can you help me with some info?

Hi mrdarwin
I've  checked the schematics and I think you are right!!! :-\

another question:
I'm using output transformer
The components that I can omit are these?
R38-39-40-41-42-43-44-45-46-47-48-49-50
C15-16-17-18 and 5532
and same for other channel
Correct?
Something else?
If DOA are used all the 22pf must be omitted?
Thanks

Thanks

 

[Esoterimix]

Yeah, but what about those of us who ordered a 1ru case, or one of Dan's chassis? There's gotta be a way to work around that error... Hopefully.

 

[mrdarwin]

This is how i plan to mount them. I will have headers giving me enough height to clear the resisters. and I can mount mine up becasue I will be using a 2u (maybe even 3u) case

I think I will use some wires connected to a custom tube support I will build outside the pcb...
I was already planning to use a 2u case, but its a bad new for people who want to use 1u case like dan's case....

 

[prh]

OK, so we have routing errors on the DOAs, routing errors with the tubes... and next???

I have tubes, audio transformers and a power transformer for this project.

I won't commit any more time or money to this build until someone can demonstrate a Rev 4 unit finished and working.

 

[berkleystudios]

This is how i plan to mount them. I will have headers giving me enough height to clear the resisters. and I can mount mine up becasue I will be using a 2u (maybe even 3u) case

I think I will use some wires connected to a custom tube support I will build outside the pcb...
I was already planning to use a 2u case, but its a bad new for people who want to use 1u case like dan's case....

I would suggest people with a 1u do that as well but Im not sure they will have the room. its pretty tight with the power and out put trannies with these big pcbs

 

[berkleystudios]

OK, so we have routing errors on the DOAs, routing errors with the tubes... and next???

I have tubes, audio transformers and a power transformer for this project.

I won't commit any more time or money to this build until someone can demonstrate a Rev 4 unit finished and working.

currently saving for an orion so I wont be done with mine till after I get that most likely. but even with a few mistakes I still think this build will go just fine. and It really isnt that expensive if you dont want it to be. the price is really dependent on how creative you want to go with this thing.

 

[mrdarwin]

I think its a really hard work to create and design an experimental and personal project like this, I would to be able to do... It is not a clone guys!

thanx to abe and lets contribute to make the prr176 better!

 

[berkleystudios]

abe

say I really wanted to be adventurous with this build and wanted to put a pair of ba283 cards to drive my output. any idea where i would wire it to the board and components I could leave out?

 

[berkleystudios]

Thanks berkleystudios
I also think something like this!

Can you help me with some info?

Hi mrdarwin
I've  checked the schematics and I think you are right!!! :-\

another question:
I'm using output transformer
The components that I can omit are these?
R38-39-40-41-42-43-44-45-46-47-48-49-50
C15-16-17-18 and 5532
and same for other channel
Correct?
Something else?
If DOA are used all the 22pf must be omitted?
Thanks

Thanks

i know that if doa's are used omit the 22pf caps. do not know about the transformer option.

 

[mrdarwin]

Ilfungo, what kind of xformer will you use? what ratio?

 

[ilfungo]

Hi mrdarwin
I don't know
I've different trafo and will try some experiment
4 x LL1540 ( input/interstage)
4 x LL139  ( output)
2 x Marinair T.1148 ( 10k/2k5 : 9k6/2k4 ( 2 x 5k : 2 x 4k8 windings ) for input
2 x edcor PWC 10k:10K interstage ( on 176 REV 2 good sound but bad noise captured from the tubes)
I hope in this rev that noise is gone..

and I've also 4 x
marinair T1720 perhaps 600:600 interstage
2 x carnhill VTB 2281 - 600:600  output....

 

[mrdarwin]

Hi mrdarwin
I don't know
I've different trafo and will try some experiment
4 x LL1540 ( input/interstage)
4 x LL139  ( output)
2 x Marinair T.1148 ( 10k/2k5 : 9k6/2k4 ( 2 x 5k : 2 x 4k8 windings ) for input
2 x edcor PWC 10k:10K interstage ( on 176 REV 2 good sound but bad noise captured from the tubes)
I hope in this rev that noise is gone..

and I've also 4 x
marinair T1720 perhaps 600:600 interstage
2 x carnhill VTB 2281 - 600:600  output....

well... I believe if you use (and me too) a 600:600 xformer for output, you dont need to remove some components. Can someone confirm?

 

[druu]

6x DOA's? I've only received 2! (joined to the tube sockets).

 

[abechap024]

Can someone tell me how many DOA's we were supposed to receive?

None. They were included at random as a "bonus". But if you want a total of 6 I will send you some, because the footprint on the board is upside down.

I've noticed the biggest benefit when I use just one on the makeup gain opamp position. At least in the past when I've done the tests. I haven't tried this one with all six yet. I am using all monolithic chips on the build I just put together and there isn't one thing I would want to change about it!! Haha I don't even care right now if it even has discrete opamps or not cause I am just really excited on how it sounds. Even more so then the Revs before this one.

 

[abechap024]

Yes mount the tubes straight up.

 

[abechap024]

Ilfungo, what kind of xformer will you use? what ratio?

1:1 for everthing is fine. Others will work but watch frequency responses..

 

[abechap024]

Yea. If u already got dans case shoot me an email or pm and I will get some other tube mounts made....sorry guys,

I made mine standing up in a 2ru. And it does work very well. even in spite of all these things, it is by far my favorite compressor now

 

[abechap024]

2 x edcor PWC 10k:10K interstage ( on 176 REV 2 good sound but bad noise captured from the tubes)
I hope in this rev that noise is gone..

and I've also 4 x
marinair T1720 perhaps 600:600 interstage
2 x carnhill VTB 2281 - 600:600  output....

You need shielded interstage transformers if you are experience hum. Thats why i used cinemag, some people still wanted edcor because they didnt seem to get any hum? Or they shielded the edcors themselves. Get shielded interstage, much easier than messing with it.

 

[tazwolf]

Are the tube mount pcbs single or double sided? If they are single sided i can try and etch my own as i need them horizontal for Dans case.

Has anyone found a supply of 47uf 45 volt bipolar electrolytics with a 2,5 mm lead spacing?

/taz

 

[abechap024]

Are the tube mount pcbs single or double sided? If they are single sided i can try and etch my own as i need them horizontal for Dans case.

Has anyone found a supply of 45 volt bipolar electrolytics with a 2,5 mm lead spacing?

/taz

You could cut all the traces at the connector and use wire to invert them all. Otherwise I am going to do a quick run of tube mounts flipped so the can be used horizontal. Everyone that needs them, just leave me a note of what you need at [email protected] and I'll make sure you get them.