Pioneer SA-8800

[Lorne]

I bought a Pioneer SA-8800 integrated amp yesterday for about $50 US here in Sendai, Japan. It was in the Junk section — take-it-or-leave-it-no returns. As soon as I pulled the hood I was in love. I am currently restuffing its companion Japanese domestic model tuner, the TX-8800 II, so I instantly recognized some production similarities.

I was anticipating a rather boring sound. WRONG! After Deoxing the pots and sweeper selector, I spun an LP on a Micro DQ-5 TT with a Denon MC 301 II cart. The performance astonished me — particularly considering that this unit appears untouched after 28 or so years — dry old Elna electros and all. I immediately knew that I would try to completely rebuild this gem, even though comments on this forum regarding the replacment/substitution of transistors in other Pioneer projects seem very discouraging. I have played this album on some good amps in otherwise the same system, so I had references to go by.

AN IMMEDIATE CONCERN
There is the same left-channel racket as another writer addressed in his 5XXX series SA. I thought of the usual suspects: a bad transistor, dirty connections to the grounding plane , leaking capacitor/s or — all the above. The scratching noise is not an issue on strong signals — at volume. But at idle with no signal, or with very low signal it gets worse and worse until the volume is pushed up again.

Anyone care to comment about ANY part of this post? Are there other Pioneer SA maniacs in addition to the SX species? I have done a search on this forum, but I see that I am going to need as much info, advice, stories and suggestions as I can find, listen to or read.

I have just tried attaching an image, but the site interface keeps failing to either post or put up the image attachment. You WOULD notice the absence of floruescope windows, and there is a chromium plated balance control wheel behind the volume knob. I can only guess that it was a domestic varient. Of course it runs on 100 VAC, 50-60 Htz.

All the best — Lorne

[djk]

Look for 2SC1345 transistors, small plastic types.

If you find any, replace them all, they had a bad batch in the late 70s that developed popcorn noise.

[Peter Daniel]

Here's the schematic of the output stage. If you are interested, I can e-mail you the high res version.
http://www.diyaudio.com/forums/attac...&postid=157673

[destroyer X]

This way we will be happy together!

regards,

Carlos

[Peter Daniel]

hi Carlos,

you asked me for nakamichi schematics. I only have zxl 1000 deck manual. I don't think it would be of any usage for you, wouldn't it?

[anatech]

Hi Peter,
You had me excited, I was about to ask you about CA-5/7 and PA 5/7 schematics. I wanted to study them some more.
-Chris

[Lorne]

Thanks for the hint DJK. I will be looking for those transistors and will change them out if I find them.

And PETER, I would be very grateful for the hi-rez version. I downloaded the doc you referred to from the archives before I put up the thread, but I can't read it on the screen rez.

UPDATE
The next day I powered the SA up and tryed to play a disk, The noise was more aparrent and gradually grew so loud that I powered down. Looks like I had better change out the caps and get a tech or someone to power up on a variac and scope. I am thinking of changing out the transistors at the same for more modern equivalents if available.

I found out that someone has been inside before me and has taken the wiring out for the Pre-amp out. So I really need a service manual eventually. And it may have to be specific to what seems this Japanese domestic varient. But Peter, the hi-rez output schematic would be a great start. I am suspecting that the output schematic for the the flouroscope models includes the same circuit as mine.

There is a reason why I will go to the trouble of restoring this amp — even though it may not be the world beater that some may claim the Luxmans and Macs of the same vintage were. Firstly I own it. Secondly it did not cost a fortune. And thirdly it is an all discrete amp, and I believe we are hearing a distinctive sound from such a unit. It suits my taste anyway — or would if it were working properly. Does it anyone elses? Who else owns an 8800?

Thanks you guys — Lorne

[Peter Daniel]

I will send you the schematic, but send me your e-mail first as I can't do attacments with forum mail.

If you're into that kind of equipment, you might check this thread:
Anybody into older, classic looking gear?

To anatech, I only have one Nakamichi tape deck schematic: ZXL1000.

[Peter Daniel]

Originally posted by Lorne
Who else owns an 8800?

I do

http://www.diyaudio.com/forums/attac...=&postid=50247

I also have this Pioneer receiver, which is a looker:
http://www.diyaudio.com/forums/attac...=&postid=48952

[anatech]

Hi Peter,
I used to service those things. They sound incredible when set up right. Keep in mind the old Nak 20khz cal tape was about 135 deg out of phase with standard. If it's set up with the Nak tapes, skip the last azimuth tape & you'll be amazed. Also, the auto cal is sometimes off & the instructions can not be followed (trust me on that).