# Vintage Stereo Amplifier System



## ste2425 (Aug 2, 2013)

Hi all

I know we have some audiophiles on TPU so lets hope you can shed some light.

I recently got my hands on a lovely Sony TA-313 that im recapping. Lovely amplifier but im wondering was it part of a separates system? Was it part of a range that included tape decks, record player, tuner etc or was something that a user would have bought stand alone? I intend to pair it with a tape deck, record player and tuner but I would much prefer to find the original set if it was sold a system back in the day.

Thanks all Stephen


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## McSteel (Aug 2, 2013)

It was a stand-alone integrated amp, AFAIK.

What are you recapping it with?


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## ste2425 (Aug 2, 2013)

Well I haven't yet.

I get the sense this is where you show up my limited knowledge and say there's nothing to cap....

I haven't even opened it up yet. Waiting for my first pay check from my new job then ill be going through restoring it. Lots of googling I think will be in order when it happens.


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## Frederik S (Aug 2, 2013)

See how it sounds first. Then replace what looks damaged. 

Contact cleaner and toothbrushes will be needed  

Good luck it is a beauty!!


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## ste2425 (Aug 2, 2013)

Yes every google hit recommends contact cleaner for the potentiometers 

It does sound good but its very picky as too its sound source for the quality of output. I don't mean specific inputs on the amplifier but if i hook the same input upto my tv then my iphone it takes allot more effort to configure the sound options on my tv to get it sounding good compared to my iphone. I also have a pioneer sa-520 and thats lovely. 

Not just that theres some issues with the mute not muting, nearly all pots buzz when turned(contact cleaner there) but most of all i think im suffering some form of ground hum. The power cable has no earth but when i turn it on from both speaker outputs i get a very low hum through the speakers. Doesn't matter what input i use or if i even connect a cable up to any. The volume makes the hum louder after about half way up below half way it seems to make no difference. I did notice strangely that sometimes touching the case caused it to go quieter for a second, not every time it was a bit hit and miss. But like you said i need to open her up and have a look 

Just wish it had power outlets for my tape deck, record player on back like the pioneer. But i do love the proper VU meters and the built in spring reverb  don't get that on modern junk (even though on paper modern stuff is better in every measure) 

I also found this in the house i just moved into, haven't used it yet but its bloody cool  No idea if its of any quality when it was new but still brilliant


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## Vario (Aug 3, 2013)

ste2425 said:


> Yes every google hit recommends contact cleaner for the potentiometers
> 
> It does sound good but its very picky as too its sound source for the quality of output. I don't mean specific inputs on the amplifier but if i hook the same input upto my tv then my iphone it takes allot more effort to configure the sound options on my tv to get it sounding good compared to my iphone. I also have a pioneer sa-520 and thats lovely.
> 
> ...



nice ghetto blaster


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## McSteel (Aug 3, 2013)

ste2425 said:


> Well I haven't yet.
> 
> I get the sense this is where you show up my limited knowledge and say there's nothing to cap....
> 
> I haven't even opened it up yet. Waiting for my first pay check from my new job then ill be going through restoring it. Lots of googling I think will be in order when it happens.



I don't (normally) enjoy showing people up. Knowledge is gained, not born with, and there's no shame in seeking it.

But, it so happens that cap choice may not be all that relevant to how an amp will sound or perform. It's all dependent on circuit design, and there's no single best brand/model of a capacitor that will universally be good in most, let alone all amps.

There are even clever designs out there that fully avoid using capacitors in the audio path altogether, and bring their numbers down to a bare minimum (2-4) in the power supply filter stage.

That said, your vintage amp does put caps in the audio path, IIRC. Wet electrolytics at the PSU filter stage can have a minor effect, in so far as to clean up the supplied power. You don't want high-frequency harmonics nor noise entering your amplification stage.

As for the audio path, caps are used for DC (de)coupling, oscillation suppression . They can be minimized or even avoided with clever use of op-amps. If they have to stay, depending on the amp design, then you'll find that "classical" wet electrolytics will influence the soundstage, dynamic response and spatial harmony the most. Solid state caps will, in turn, define if the sound is "warmer" or more "sparkly", and the total harmonic distortion, especially in the upper range.

In my opinion, the HiFi crowd is divided into two dichotomic groups: Those who prefer transparency (i.e. as little alteration to the original recording as possible - no EQ, and no coloration) and those who prefer "the digital age" enhancements/alterations. Typically those who were exposed to live performances, with non-electronic instruments, early and often, prefer the transparent-sounding equipment. On the other hand, those who have had more contact with reproduced sound seem to prefer everything that it brings, both enhancements and distortions (to a degree).

For transparency, you want to avoid wet electrolytics completely, if at all possible. As for solid states, you want teflon and/or polypropylene (with silver foil if not too expensive).

As for enhancement, I really like how Elna RFS (Silmic II) series sound, and they're inexpensive. To add precision, you could add some Vishay MKP1837 in parallel with them, for added precision.

But what you'll probably get the most from, is thoroughly cleaning the pots, and reflowing/reworking any suspect/oxidized solder joints. This will really revitalize your amp.



ste2425 said:


> Yes every google hit recommends contact cleaner for the potentiometers
> 
> It does sound good but its very picky as too its sound source for the quality of output. I don't mean specific inputs on the amplifier but if i hook the same input upto my tv then my iphone it takes allot more effort to configure the sound options on my tv to get it sounding good compared to my iphone. I also have a pioneer sa-520 and thats lovely.
> 
> ...



It's picky because of input impedance and how the input termination is done. Can't do too much about that without drastically changing the design. As for humming, that's probably your best reason for considering recapping. Probably the ESR of some of the caps has slipped over the years, and ripple filtering (hum should be at double and quadruple the mains frequency - 100/120Hz and 200/240Hz) is now de-tuned. Also, probably some of the solder joints aren't what they used to be... But this is easily fixed. Alternately, the ground plane isn't doing it's job, if the PSU's filter stage relies on grounding to sink/divert noise to.

Well, anyway, you've got a beauty, treat her well.


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