Modifying Technics SUV78

[Bose(o)]

Hello,

Recently, I have had to order in a stereo pot for my ClassA Techinics receiver. The order will arrive in the store in about a week, and I'm getting very anxious to tackle the PCB with my soldering iron. I've looked at the capacitors, transformer and such, such that I can sweeten up the sound. I know that the receiver makes use of a solid-state transformer--considering it's LARGE size and HEAVY weight (about 10lbs.). Anyway, I can give up any info that you'd like except for things that I probably would've posted already. For example, I don't have a service manual nor do I have any schematics.


TIA, Brodey.

[richie00boy]

Solid-state transformer? That's a new one to me!

[Bose(o)]

...Suggestions?

[EchoWars]

Originally posted by richie00boy
Solid-state transformer? That's a new one to me!

play nice now richie.

What is it you want to accomplish? 'Sweeter' sound?

First off get the manual, or you're just fiddling in the dark. Then, if you want to tweak, perhaps look at replacing the old electrolytics.

(BTW, forget about messing with the transformer unless you are anxious to turn this unit into 'that thing in the basement that hasn't worked for 10 years')

[Bose(o)]

Hi,

My goal is to improve the sound, overall, by replacing current components. I read a thread here, where someone 'sweetened' up the sound of his Nikko (or something) amplifier by changing op-amps and such. I'm pretty sure I don't have any of the usual 6- or 8- pin (I forget), op-amps. The only amplifier IC, that I can see is this LARGE piece...I'll post up later with more info..


Thank you for the suggestions...


Oh yeah, I'm in the dark, no manual...in fact I can find a lot of newer Technics receiver mods and such, but not for my version.

[millwood]

Originally posted by Bose(o)
My goal is to improve the sound, overall, by replacing current components. I read a thread here, where someone 'sweetened' up the sound of his Nikko (or something) amplifier by changing op-amps and such.

well, just a word of caution:

1) what the other person considered "sweet" may or may not be sweet to you at all. sound is quite subjective.
2) what the other person perceived to be "sweet" sound may or may not have existed in his/her system at all. People hear things all the time because we simply wanted to hear a difference, a better sound as return for our labor or money spent.

[Bose(o)]

Never thought of that. Thanks for the heads up though.

Anyway, is it possible to 'better' the sound of a receiver (in theory), by replacing caps to 'higher quality' caps where, switches and tone controls would also receive the same treatment?

[KevinLee]

Hello Bose(o),

Does this unit have discreet output transistors? It sounds to me like it might have a big old STK module. If this is the case I would not do much more than cleaning the amps controls with some Nutrol.

If you do have an STK module as your driver/output section, you may want to look for an older discrete output piece to upgrade (Akai, Sansui, Rotel, NAD, HK etc.).

Good luck.

Kevin Lee

[SkinnyBoy]

Originally posted by KevinLee
Hello Bose(o),

Does this unit have discreet output transistors? It sounds to me like it might have a big old STK module.

I am fairly sure it does... and, from what I have read these aren't the best... lol if you're up for a challenge, then replacing this IC with a pair of LM3886's or something similar is quite possible..

[Bose(o)]

Yup, nice large STK as it goes....SVI 3205 is the code marked on the package.

Wouldn't there be different power requirements for different STKs?

hmm...the LMs...possible, but slightly difficult...I'm guessing that I'd have to buy a seperate circuit board and run the wires as they correspond to the PCB. I may also need a new heatsink...though, I'd guess the current amp IC is fine.