Schematics for Neve BA438 and BA440?

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Flatpicker

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Jun 3, 2004
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Anyone got schematics for these, particularly the BA438? Used in the 1091, I think. Info on these seems to be scarce. I can reverse engineer it, but of course, having the schematics is much easier.
 
http://www.vintagedesign.se/diy/B338_Schem.pdf

and

http://www.vintagedesign.se/diy/B340_Schem.pdf

both of which are from the Tommytones 1081 DIY page over at TK's site,

http://www.vintagedesign.se/diy/index.htm

The schematics are for the BA338 and BA340, but these are the same circuits as the BA438 and BA440, respectively. The difference between the 3xx and 4xx versions is the 3xx versions had narrower pins for connecting to the motherboard, so they fell out easier than the 4xx versions. Same circuits, however.

So do you have 1091's? Those modules are from the EMI/Neve's, and I understand that they have 10468's transformers for the line inputs instead of 31267's used in other Neve gear. Is this true, and have you ever compared them to, say, a 1081 to see if there's a noticable difference sonically between the line inputs of the two?

I would love to know.

Peace,

JC
 
There are some minor differencies between the 3xx and 4xx serie, send your e-mail and I'll send you a copy, know I have it somewhere!
 
Differences? Really? I've only ever heard about the physical pin difference.

Can I get a copy of that info too, TK?

My email is r7fm(at)integrity(dot)com

Thanks man!

:thumb: :green:

JC
 
Thanks, guys! :thumb:

JC - I don't have a 1091 - I actually meant to say "1081", but looks like they are used in the 1091 as well.
 
[quote author="Tekay"]1081 used 338/340 31105/33114/33115 used 438/440 IIRC!?[/quote]Did the 1081 use both? The reason I ask is because John Klett refers to replacing both 338s and 438s in the 1080 troubleshooting section of his Neve "80 Series" Modules article. May just be a typo.
 
There are other versions of these amp PCBs, the 638 & 640, which use ICs driving a comp. pair transistor output. Interestingly enough, I have swapped them in 31105 Mic Pre/EQs in the 8078s that I used to take care of, and NO ONE could tell the difference.

My friend Fred Hill in Nashville maintains that the sound is in the XFMRs, and I tend to agree.

From what I know, and the consoles I have worked on, the 6xx series were designed for the 8088 series of consoles, which are large frame 8068s, using 31102 Mic Pre/EQs. These were the consoles built for the AIR studios, that wound up at A&M/Henson, Bryan Adams studio, and a few other places.
I currently take care of a lovely 40 ch. 8088 in Burbank, CA.
 
Thanks for the info, Stephen and welcome to the Lab! That's interesting about folks not telling the difference between the 4XX amps and the 6XX amps.

What output transformers does your 8088 use? Seems that there are lots of options for input transformers, but I'm having trouble finding output transformers for these things. I know an API 312 type will work since it's not DC gapped, but I want to use what gets me closest to that "Neve" sound.

BTW, anyone have schematics for the 638 and 640?
 
[quote author="Tekay"]1081 used 338/340 31105/33114/33115 used 438/440 IIRC!?[/quote]Tekay, for the record, you are correct. According to Geoff Tanner, any 1081 with a 4XX amp has been modified. (It's taking me a while to piece this stuff together! :wink: )
 

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