SUMMIT AUDIO TLA100A schematic?

[OlympicPhil]

Hi,

I have a TLA 100A in my workshop which needs repairing.
It's blowing the main fuse about 3 seconds after switching on (probably a power supply or blown capacitor problem) but I have no schematic for it.

Does anyone have a schematic for this unit that they could let me have a copy of?

Also, the fuses inside say 1/2A

I've never seen fuses with their ratings given as fractions before, so are they actually 2A fuses or are they just from some bizarre batch of fuses that say 1/2A meaning 500mA?

Any help would be greatly appreciated.

Phil

 

[gyraf]

Hi Phil,

I've never been able to find schematics for the summit stuff - I spent much time searching for them some years ago. No luck. So if you find them, think of us schematic-hungry beasts over here, please?

½A fuses are just an old notation. Use 500mA - but be sure to use the same type (slow, med or fast)

The Summit boxes contains a lot of standard IC's and a couple of tubes. I don't think they're running starved-plate, but I have a feeling that the compression is not tube-related at all.

Jakob E.

 

[SSLtech]

I thought that the TLA was supposed to ba an optical compressor, and I thought also that the input & output was supposed to be transformerless.

-It's perhaps an iterarion of an LA-2a topology with the "Mastering Lab" updates built-in...? (The Mastering lab was famous for removing the input & output transformers from LA2a's and making them all-tube-transformerless...)

keith

 

[Guest]

Phil
since you are from Olympic and might have a few schematics lying around in a cupbaird - any chance of havign a look at this thread for us..
http://www.groupdiy.com/index.php?topic=1222&highlight=helios

 

[Kid Squid]

'Allo Chaps,

Olympic Dave, one of my mate's used to own one of these, and although I haven't got a copy of the schematic - I can remember seeing the schematic in the User Manual. try and get hold of a copy :thumb:

If my memory serves me correctly, The TLA100A , is not a true valve compressor (Vari - Mu), the valves are there for input and output warming !
Sort of like a prettier optical TL audio comp.

anyway, hope this helps :grin: :guinness:

 

[tubejay]

Yes, it's my understanding that they are optical compressors based on the La2a. It believe it has 990 amps inside, so I think the tubes are for warming. I had to open one up once to replace the lamps. I don't recall seeing transformers inside, but I could be wrong. I definetely remember seeing 990's in there though.

All I really know is that the TLA100a is a F'n awesome compressor for vocals and strings/acoustic guitar. It's a smooth sounding compressor. I would love to build one!

 

[mesmer]

This one was dasigned by Dan Hill of Cranesong, in his early days.
Peter

 

[wilebee]

Dave hill would might be a good source

Wil

 

[fum]

That or call Summit directly. I've a DCL-200, and they were right courteous about providing a schematic and calibration info for it ( after I faxed them a signed NDA of course)

Regards

ju

 

[JPrisus]

A tech friend tried getting a TLA100 schematic from Summit a few years back and they gave him much grief about it. Even though he was more than qualified, they made him send the unit back and pay all sorts of shipping.

IMHO, Dave Hill MADE that company what it was. It's a shame what happened really.

 

[peter purpose]

Here's a block.

 

[gyraf]

The blackbox "Compression cell" it uses seems to be an oldfashioned transistor-array VCA, judging ftom the three associated trimmers. Not an opto or vari-mu compressor for sure - more like the "tube" compression in the Drawmer 1960:

Summit TLA-100A Schematic:

http://img.photobucket.com/albums/v172/gyraf/Summit_TLA-100A.gif

Jakob E.

 

[OlympicPhil]

Hey, thanks everyone that's helped me, I've now got 3 copies of that schematic, 2 user manuals and 2 copies of the line-up procedures.

I'm blown away by the help I've received, so a huge thank you to everyone.

I've traced the problem back to two big black plastic blocks filled with hardened resin that looks as though they each contain a pair of caps and a pair of ICs (probably op-amps?).

Are these the Jensen 990s does anyone know?

Phil

P.S. StDomingo, The B.Sc.(hons) is in Music Technology from Staffordshire University, Stafford site, class of 2001.

 

[toby]

maybe a stupid question but whys there no biasing resistor on either of those tube stages?

 

[peter purpose]

Phil,
If they are indeed Jensen 990's, then they are discrete op amps.
Available from John Hardy. http://www.johnhardyco.com/

I could pop round with 990 compatibles for you to try out.

peter

 

[Kid Squid]

Hello Phil,

'I'm blown away by the help I've received, so a huge thank you to everyone'

Phil, This goes to show how everyone else on this forum feels :grin:

everyone needs some help now and again, some more than others !!! ( like me :grin: )

anyway, i hope you get what you need,

Best Regards

Steve :thumb:

 

[Steve Jones]

I have repaired a lot of TLA 100A's, Eric at summit kindly provided me with schematics after I filled an NDA. You have a faulty 990 module, (the 2 black boxes.) I have seen this problem many times before, and have replaced quite a few. Really I think there needs to be more DC decoupling on the 2 990 modules in that unit, they blow quite often.

Nice compressor though....

 

[audiocraft]

Hi ,

I have repaired some of those units as well and after replacing their 990 clones by John Hardy 990C devices I never had any problem .....

IMHO most of the 990 clones made by Summit are not quite up to spec and have an annoying tendency to blew of .......
:evil:

BTW if upgrading the opamp don't forget to use the PCB sockets as the Summit pcb's are a pain to work with ...... !

:guinness: :guinness:

Luis

 

[Lindell]

I have two TLA100, they are just great compressors on vocals !
Anyone up for cloning........? heheheh

 

[gyraf]

The "compression cell" is potted - probablt not because it's secret brilliant circuits in there, but to stop technically minded custoners realizing that it's not really a tube compressor after all.

Jakob E.