Pioneer SA-710 Amplifier

[Scott_drake]

Hi

I have recently aquired a Pioneer SA-710 integrated amplifier. I have tryed to get information on this amp from the net but i cant seem to find much.
As this Amp was made between 1978 - 1980 it would probly be worth replacing some components. What components should i be looking at replacing. Ive opened it up and cleaned it up and all the components are in good cosmetic condition. The Amp does seem to sound very good, although some clipping or distortion as it is turned up towards its 65W max power (as seen on the front bar meter).

What steps should be dont to refurbish this unit?

Does anyone have any information or experience with this model.

[Scott_drake]

Oops wrong image in previous post. How can i delete the previous pic?

[Scott_drake]

please help.......

[pioneerboy]

It's a pretty dreadful piece, introduced to fill out the budget end of the otherwise very successful SA series. It's prone to a lot of IM distortion and pretty uninspiring generally. It's not even heavy enough to make a good doorstop. A large ashtray, perhaps?

[audiomachines]

hello,

It's basically the same with the SA-610 and SA-6000, the tone control is incorporated within the NFB section of the power amp. You can download the service manual at www.hifiengine.com I have restored a few units myself. Recapping the power supply would be a good place to start.

Best regards,
audiomachines

[sakis]

last night ......

at this age the only thing you need to do is just a recaping .... and all information you need can be found here ....vintage amplifier repair/upgrade manual more or less

[rabbitz]

Forget about the stupid comment on ash trays and doorstops as it's not constructive.

I have recently done up a SA-610 which would be very similar. It ended up replacing a NAD C315BEE in a secondary system which is used every day.

Mods were:
* Replaced main power supply caps with the next size up in my case from 8200uF to 10000uF using Elna caps from a A400X.
* Changed signal caps 1uF or less to MKT or MMK and those >1uF to Nichicon Muse ES with a higher capacitance (such as 2.2uF to 4.7uF).
* Changed other electrolytics to better quality but non special Elna, Panasonic FC, Jamicon etc.
* Pulled apart the source switch on the PCB, cleaned and applied Deoxit (very worthwhile as it was gunk).
* For best performance run the speaker output directly to the speaker terminals using a good cable and not the existing speaker wire in the amp (speaker inductor wire is fine as well). I still ended up using the speaker A&B switch so ran a good quality Supra cable for the runs and sounded as good as the direct connection so the switch must still be OK. I routed this away from the power and transformer wiring.
* Check all the connections on the AC power and transformer wiring as it is wirewrapped and could be insecure. I soldered and heatshrinked all of them for safety.
* Clean pots if required but all mine were like new so were left alone.
* I didn't touch any of the filter caps on the tone or phono circuits as they wouldn't be used.
* Checked the bias etc as per the service manual. There is not adjustment pots and as long as it's in spec all is well.

All in all a nice lift and liked it better than my A400X (now sold) which sounded stringent and less engaging in comparison. One problem these have is not using an active pre so can lose on extension and dynamics but partner it wisely and it can sing quite well. I use a Marantz source as well as the matching tuner and feeds a DIY bookshelf using Vifa DX25TG + Peerless 830875. I've got no complaints with the sound as it's very open, lively, good tonal balance with enough punch and drive for my needs. Partnering is the key to success. Sure, it won't keep up with my AKSA or NXV200 but it's not shamed either.

If you are experiencing clipping etc, you may have needed a more powerful amp as these are not a power house but fine at moderate levels. Even my A400X clipped very early indeed and less perceived power output than an old NAD 7220PE rated at 20W.

The other possibilty is to gut it and replace all the electronics with another amp but I don't think that's a sensible path.

There's been some good info here supply by sakis so you should be armed with a direction.

Good luck with your amp.