Two ugly and Abandoned Half-Sisters (SA-8500ii,SA-9500)

[Ian C.]

After a few years listening to my SA-9100's, I got to upgrading my listening room (room treatments) and my speakers (OLA->Monitor Audio Silver 100's) and have since been fiddling withe the componentry. Long story short, after having tried various setups I love how things sound with the sa-9100 amp between the schiit saga preamp and my monitor audios.

That said, I was bottom fishing the bay and got an sa8500-ii clean but wouldn't power on a year ago, and an sa-9500 that had been mistreated and left for dead. The first one just seemed neglected, but the second smelled like broken dreams Seemed like the her handler didn't even care enough to wrap her well, and looks like it got dropped on one of the cable management handles in shipping

I'd thought no power at all might be simple problem in the unregulated p/s part in the 1st unit. The 2nd unit, the seller said it clicked a second after turning it on, but no light came on. I'd guessed this might just be a lamp out. Turns out I was lucky on both. A tech fixed the former with a diode, and the latter didn't need a fix. Both amps make terrible popping, scratching, intermittent channels out in the pre-stage, but if separated and using a different pre work fine, though I haven't pressed my luck by listening to them long o hard.

So I'm interested in interviewing each of these amps between my schiit pre and my monitor audios. After the last ordeal with my 2nd sa-9100 where another tech had added workarounds, subbed wrong parts, reinstalled boards with resistor legs lifted out of circuit, I had sworn not to inflict audiokarma or myself to another repair, yet starting with working (kinda) units seem a more known quantity.

I'm not sure, but I feel like best practices have changed in the last 15 years, but I'm thinking, power supply board(s), amp board(s), main caps? I'm not sure from the threads I've read if this means all transistors or just the problem ones, all electrolytics with thoughtful substitution with film caps, and new trim pots. For my purposes, other than de-oxit I'd leave the pre stages alone for now?

 

[Colleton]

I've been working on a receiver recently with a lot of popping and noise in the preamp. I had thought that it was a bad transistor or two on the tone board (and it may well have been a factor), but the big issue ended up being a bad speaker protect relay. It would just randomly arc and pop on its own, and do it consistently if I tapped it with my finger.

I bought a moldy old 9500 II at the end of last year. It worked but smelled like a mix of mildew and dirty ashtrays. It was a lot of work, but I love it now. You'll like your 8500 II once you get it going, I think. I have a 9500 as well and it's one of my favorites. Unique.

I am far from being an expert, so grain of salt... I have definitely been in the "replace everything!" camp for the most part, but this year I've been experimenting with just aligning and enjoying new equipment or recapping the electrolytics and replacing only the transistors on the bad list. That's worked pretty well for the equipment I've tried it on. As for your last question, if you're going to do it then I'd do all the boards. I usually replace the filter caps, but I don't think I've actually found a bad one yet though. YMMV.

Good luck!

 

[Ian C.]

Thanks for the tips!

On the SA-8500ii, I'm slowly looking at this and am digging around - mine seems to be the multi-voltage version (111/120/220/240) and my "AWs-108" seems to be instead aws-113, that sound right? Anyone seen a different schematic for this? It's also silkscreened anp-549 preamp board.

 

[Ian C.]

Thanks for the tips!

On the SA-8500ii, I'm slowly looking at this and am digging around - mine seems to be the multi-voltage version (111/120/220/240) and my "AWs-108" seems to be instead aws-113, that sound right? Anyone seen a different schematic for this? It's also silkscreened anp-549 preamp board.

on SA-8500ii:
aws-110 - on KC (120 Only, Canada only)
aws-108 - on KU (120, USA only)
aws-113 on s (110,120,220,240)
aws-112 on hg (220,240)

Models S,HG,KC covered in supplementary service manual:

Manual: SA8500II SM PIONEER : Free Download, Borrow, and Streaming : Internet Archive

Manual: SA8500II SM PIONEER

archive.org

 

[Ian C.]

Think I'm going to just round robin my upgrades of these two amps checking along the way I'll catch it if I screw up.
Recapped 8500ii aws-113 that I'm guessing contains the protect circuit and power supply awh-051's amp boards - sounds good including the pre stage, but I'm only listening with headphones.

Are there draining resistors on these big caps or are mine just not holding a charge? Any current part numbers for the big caps sa-8500ii? All the #'s I see from the threads I look up seem out of stock.

 

[Colleton]

I just checked and the Nichicon Muse caps I used for my 9500 II are no longer available at mouser or digikey.

This one from Kemet is available on Mouser, it should work: 80-ALC10C153EF063

15000uf / 63v
40mm diameter, 50mm length

GL!

If someone else has a better choice please chime in.

 

[Ian C.]

thx!!

 

[ivandezande]

Think I'm going to just round robin my upgrades of these two amps checking along the way I'll catch it if I screw up.
Recapped 8500ii aws-113 that I'm guessing contains the protect circuit and power supply awh-051's amp boards - sounds good including the pre stage, but I'm only listening with headphones.

Are there draining resistors on these big caps or are mine just not holding a charge? Any current part numbers for the big caps sa-8500ii? All the #'s I see from the threads I look up seem out of stock.

I always use these in SA-9500ii's. Bump in voltage means they'll last longer.

382LX153M080N082 | DigiKey Electronics

Order today, ships today. 382LX153M080N082 – 15000 µF 80 V Aluminum Electrolytic Capacitors Radial, Can - Snap-In - 4 Lead 3000 Hrs @ 85°C from Cornell Dubilier Knowles. Pricing and Availability on millions of electronic components from Digi-Key Electronics.

www.digikey.com

 

[Ian C.]

SA-9500ii and sa-8500ii same caps?
while we're at it, good caps for the SA-9500?

 

[hansjoakim]

SA-9500ii and sa-8500ii same caps?
while we're at it, good caps for the SA-9500?

Perhaps this restoration thread can be useful for the 9500, it was for mine!

SA-9500 Restore

My first time seeing a SA-9500, was surprised as the driver board resembled the 950 I did recently almost 1:1. I performed a full recap, replaced all transistors minus outputs, trim pots etc. Needed a thorough pot cleaning and had the crackle/pop due to the matched transistors on the driver...

audiokarma.org

 

[Ian C.]

That's a great thread! I don't see it called out, but if I engage my safety squints I think I read Nippon Chemi-Con 18,000uf 75V 95 degree, but looking for a part #

 

[Ian C.]

SA-9500ii and sa-8500ii same caps?
while we're at it, good caps for the SA-9500?

note to self, ALT22A153DE063 for sa-8500ii backordered, 40mmx70mm

 

[Ian C.]

After wrestling with an idle problem and then royally self inflicting some damage on an innocent amp board, the sa-8500ii is back among the living.
De-oxited contols, (I think) power and protect circuit, big caps and renewed amp bords. Eager to compare the amp stage to the sa-9100 amp stage and see if there's any audible difference.

By the way, I learned if you have a labeled bag of transistors, it doesn't mean there's not a different transistor in there to wreck your day if you don't verify.

On to the SA-9500...

 

[Ian C.]

I rotated out the sa-9100, and am now auditioning the sa-8500ii in it's place, and am running the power stages off a schiiit pre-amp.
I must say, I am very surprised at the difference. I figured both amps are supposedly flat in the audible range, so there would be marginal difference.
It's subjective, but FWIW, the sa-8500ii sounds like it has the loudness on compared to the sa-9100. In think with this there is quite a bit more dynamic range on the sa-9100 - it can be quieter,and louder, and a lot more in between. I'd almost think something was lacking in the sa-9100, but I have another and it sounds the same, so I think the sa-8500ii has something extra. The sa-8500 is fun and seems to want me to crank it. The sa-8500ii seems to have a voice/timbral character closer to my sx-650.
The sa-8500ii seems to have noticeably better separation and a wider soundstage than the sa-9100. I was surprised here, because I've tried actual paired monoblock amps, vs. dual transformer of the sa-8500ii in the form of dual NAD 2100pe and dual Parasound HCA-70a and didn't notice much difference. The 8500ii sounds great with video or what I'd call 80's music.
I'd say the sa-8500 is more of a crowd please, while the sa-9100 is better for critical listening. I think I might get a niles speaker/amp switch to make the comparisons less subjective. I was expecting that much different a sound in the pre stages, but now the power amps. The difference was obvious I think you could hear it in the next room with the door shut.
SA-9500 is next, after power/protect,amps and new filter caps and a good scrubbing.

 

[lorne]

.... SNIP ....
Recapped 8500ii aws-113 that I'm guessing contains the protect circuit and power supply awh-051's amp boards - sounds good including the pre stage, but I'm only listening with headphones.

Are there draining resistors on these big caps or are mine just not holding a charge? Any current part numbers for the big caps sa-8500ii? All the #'s I see from the threads I look up seem out of stock.

I am not an adept technician. But I cobbled an SA-8900 into one of my favorite pieces. It was a lot of work. I took on each board — one at a time. I use it as a pre-amp these days. Luv it!!

• Your SA-8500II is the younger successor to my Japanese SA-8900.

• Just replace the filter caps with similar capacity and voltage rating that is already in there. Don't fret about replacement part numbers. (A pointless exercise all these years later anyway.) Standard Chemicon / Nippon Chemicon cans will do you fine. You may have to do some adjustments as to how they are installed. (See my attachment.)

• I dunno about your 8500II, but there is a short list of some dubious transistors in my 8900 — a pair in particular. (I've got the parts, but I still have to get in there and do a changeout — different form factor.)

If your 8500II lives up to or exceeds my 8900, you'll love it — dynamic and yet nuanced. Baby sit and be kind!

 

[Ian C.]

Successful in washing some of the smellof broken dreams away....
Need both side panels still, and washing some nicotine off the PCB's with isopropyl and can then consider re-releasing her into the wild.

 

[lorne]

I hope you keep at this project and get at least one of these units exactly like you want it. (I'd be partial to the 8500II, but that's just me.) My respect for vintage Pioneer just keeps getting greater. IMHO the build quality was excellent; the performance of their premium units outstanding. They seem have survived the decades, often abused and neglected and are still restorable. It just depends on how much effort you are willing to commit. And if you do it yourself, albeit with the help of experienced and skilled members here on AK, it will be affordable and rewarding.

If I ever work on something like this again, I would order a wire wrapping tool. When you start lifting boards out to work on them or get to places you need to test, rebuild or service, you will be unwrapping wire from binding posts. The wraps on these post was (AFAIK) supposed to induce gas tight connections. The wrapping tool will get you a better reconnection than what I was doing.

My SA-8900 belonged to a smoker — maybe like yours. But you can see from my photos above that I got the boards and other stuff pretty clean. And BTW, my 8900 is now doing duty on my second system in the living room as a fully integrated unit. (These days, I have a dedicated, vintage SS preamp on the big system.) All its features are proving to be useful ... for example when I play the TV through it.

 

[Ian C.]

I'll write more later, but let's just say I can hardly believe what I'm hearing from the SA-8500ii. I can't believe they don't sell for double what they do.

 

[lorne]

>>> SNIP >>> I can hardly believe what I'm hearing from the SA-8500ii. I can't believe they don't sell for double what they do.

Unhuh ... just don't tell too many people!! There was a time when you could get a working unit here in Japan for $20. Now look what's happening! Maybe not a top model, but some really nice silver face stuff could be had for a few bucks from Pioneer, Denon, Onkyo etc. If you didn't need 100 watts .... And if I'd spurged a bit, I could have scooped some Sansui integrated amps that cost a bomb now. I was just too ignorant at the time. SIGH!!

But, in 1994 I managed to fish a pair of Tannoy III LZ 10'' Monitor Golds out of the garbage.

 

[Ian C.]

Nice! The SA-9100 is really nice and I get why it sells at a premium, but there are a few others that are a steal even at 2024 prices.