WTB: Neve BA438 opamps

[Golgoth]

Hi,

I am looking for BA438 opamps, please PM me with your offer/quantities if you want to sell some

Thanks,
G

EDIT: Sorry, posted that thread in the wrong section!

 

[noizetoys]

If you want to build them yourself try:

https://analogclassics.com/product/neve-ba438-replica-pcb/

 

[Golgoth]

@noizetoys Thanks! I'll check them out. I am restoring an old Neve module and would like to have everything original, but that could be a solution!

 

[noizetoys]

I just ordered a pair of boards, I'll let you know how they work out. I have several 3415's so I need some spares. I found another guy with boards for 512's. I was planning to order some of those to try out.

All original is nice but just so expensive these days.

 

[Golgoth]

I just ordered a pair of boards, I'll let you know how they work out. I have several 3415's so I need some spares. I found another guy with boards for 512's. I was planning to order some of those to try out.

All original is nice but just so expensive these days.

Indeed, very expensive, but luckily about only 5% of the unit's components I am restoring!

Let me know how you like the Analog Classic's boards, I may try their BA283's boards for a different project.

 

[noizetoys]

I received the boards today. look like an accurate copy of the 438 board. Now to see if I have the components to build one.

One of my concerns is the transistors. I looked at AML's ez3415. For the 438, all of the 'gain' transistors are BC550/560 and the 'output' transistors are BD139/140. I've got plenty so I'm going to give those a try and compare them to 'original' 438's. Will there be a significant difference? I doubt it, maybe if I crank the hell out of the gain, but I'm not expecting anything too noticeable. Welcome to the land of confirmation bias!

Out of curiosity, what are you restoring?

Happy Last Day of the Calendar!

 

[Golgoth]

I received the boards today. look like an accurate copy of the 438 board. Now to see if I have the components to build one.

One of my concerns is the transistors. I looked at AML's ez3415. For the 438, all of the 'gain' transistors are BC550/560 and the 'output' transistors are BD139/140. I've got plenty so I'm going to give those a try and compare them to 'original' 438's. Will there be a significant difference? I doubt it, maybe if I crank the hell out of the gain, but I'm not expecting anything too noticeable. Welcome to the land of confirmation bias!

Out of curiosity, what are you restoring?

Happy Last Day of the Calendar!

Happy New Year!

I am not too sure about what difference using different transistors would make actually, but I'd love to hear back from you if you experiment!

It's a Neve "Audience Reaction Mixer". Ten 1081/1073 preamps (without EQ) into 1 output, in a 1U 19" rack which is pretty awesome. The unit I bought is pretty beat up and is missing some parts. I am gathering what I need at the moment. I am going to rewire everything neatly, then add a second output for stereo summing so I can track stereo sources / sum busses. Lastly I will add a couple microphone transformers and switches to be able to choose between line/mic on a couple channels (the unit I have only has line input transformers for now). I will post a thread when the job is done!

 

[noizetoys]

Have you considered running the 32167 backwards as Mic transformers? I think I ran across a thread about using a switch or relay to change the input from line to mic by changing which windings are used.

Here's an article form Jim Malone (JLM Audio) about using different transformers for mic inputs.

http://www.jlmaudio.com/Neve transformer info.htm
I look forward to seeing what you come up with.

 

[Golgoth]

Thanks a lot for reminding me using the irons "backwards" is possible! I always thought that using a transformer like that would depreciate its qualities but the page you linked says otherwise which is very interisting.

I will try to figure out how to implement the switch, and probably save quite a lot if money thanks to you haha!

 

[Rob Flinn]

Have you considered running the 32167 backwards as Mic transformers? I think I ran across a thread about using a switch or relay to change the input from line to mic by changing which windings are used.

Here's an article form Jim Malone (JLM Audio) about using different transformers for mic inputs.

http://www.jlmaudio.com/Neve transformer info.htm
I look forward to seeing what you come up with.

Years ago I tried using this info with some Mariniar 31267 & found it didn't work, it hummed badly. With the particular transformers I used it hummed badly. From memory I found that I had to reverse the polarity of one of the winidings to correct it & then sort out the phase at the output xlr. If you have problems try searching here for my post in about 2004.

 

[Golgoth]

@Rob Flinn I have not tried the JLM method yet with the 31267s. Will definiteley do tho and report back how my transformers handled the method!