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Pioneer SA-8800ii recap

jojo0416

jojo0416

aka Karipas
Finally, I decided to get my hands dirty and wanted to start with my smallest integrated. I have downloaded the manuals of SA8500ii from the database. Anyone who has recapped this amp, I would be very thankful if you can share me your parts list. I want to start with the power amp section. I had electronics class 28 years ago so I need to jog my memory with your guidance. I have the following questions to begin with:

1.) Can I use RoHS solder for this job? What size, I see there are different sizes of solders. I only have an ordinary iron, no temp adjustments.
2.) How do you remove and return the wires from the connections, most wiring are wrapped in the terminals, can i just cut it and resolder?
3.) In buying parts, how much should I place as buffer?
4.) Is 1% tolerance for the caps always good? Or 5% fine?
5.) What is a good brand replacement for those filtercaps?
6.) Can I just do the recap leave the resistors, pots etc., I do not want to touch those yet.
7.) I am assuming its best to change the outputs xsistors?
8.) If the outputs are to be replaced, what other particular parts should go with it?
:scratch2:
I still have doubts but with your inputs will give me enough confidence to start this project.

Thank you all in advance. :)
 
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jojo0416 said:
Finally, I decided to get my hands dirty and wanted to start with my smallest integrated. I have downloaded the manuals of SA8500ii from the database. Anyone who has recapped this amp, I would be very thankful if you can share me your parts list. I want to start with the power amp section. I had electronics class 28 years ago so I need to jog my memory with your guidance. I have the following questions to begin with:

1.) Can I use RoHS solder for this job? What size, I see there are different sizes of solders. I only have an ordinary iron, no temp adjustments.
2.) How do you remove and return the wires from the connections, most wiring are wrapped in the terminals, can i just cut it and resolder?
Don't do that. Most PCBs can be removed enough to get the caps off and the new ones on without cutting those wires. If you have to, then I guess you have to, but I know a lot of people here have had lots of success without messing with those wires.
3.) In buying parts, how much should I place as buffer?
4.) Is 1% tolerance for the caps always good? Or 5% fine?
5% is fine.
5.) What is a good brand replacement for those filtercaps?
6.) Can I just do the recap leave the resistors, pots etc., I do not want to touch those yet.
Sure. But cleaning up the pots is easy and is a first step measure if something ever goes wrong with your amp. Do a search for Deoxit.
7.) I am assuming its best to change the outputs xsistors?
8.) If the outputs are to be replaced, what other particular parts should go with it?
:scratch2:
I still have doubts but with your inputs will give me enough confidence to start this project.

Thank you all in advance. :)
Click to expand...
:lurk:
 
not an expert so take my answers with a grain of salt
1. I would use silver solder if possible. At least use silver bearing (radio shack)
2. I have not done that amp, but best not to remove the wires, leave them attached and carefully flip it. Some may break, if they do, then reattach by wrapping. may not be able to wrap as much due to the length now being shorter, but do the best you can.
3. buffer? extra parts? for the most part they are cheap so I always order extra just to have them on hand. Chances are you could just order exactly what is needed. Unless you put in a cap backwards, not that easy to mess one up
4. actually you can still use the 20% which is pretty typical. amp was designed with this in mind.
5. i forget the brand name , search "Newark filter caps" run about $28 a piece for 22,000uf.
6. you do not have to change resistors. I think it may be a good idea to check the ones on the amp boards, but chances are they are still good. Usually I believe if anything, the resistor value will actually rise. I was told it was not necessary, but as long as I had the amp boards out on my Spec 2 i replaced all the resistors with 1% metal film. Most would probably recommend putting in new pots, not really a have to item.
7. I would say NO.......if they ain't broke.....do not know what it uses, but probably not your garden variety output transistor......unless one is blown, leave those be.


just my 2 cents worth. I am sure you will get some more opinions and probably much better then mine
 
Thank you guys for the first hand inputs.

@ johnnm

I was trying to figure out last night how to remove the board, I will keep it in mind avoiding cutting wires, do my best without touching 'em, besides I find the wires wrapped very neat .

Yes, I mean execess parts, how many I need to keep for each part?

So I can also clean those bias pots?


@donberry

Filtercaps mentioned are rated @ 10000uf 50V, so its still fine to use 22000uf? I do know its ok to use replacements with a bit higher cap rating same with the voltage, I just want to confirm twice the value is fine? I am trying to search newark but no results yet, I'll will measure the caps to find the nearest size.

I hope the others who have experience in capping SA8500ii can share their part list. Next step for me is to review the schematic and compare to the actual values. Will keep you posted.

Edit:

I found filtercaps at Newark, the Cornels a bit deep for my pocket @ $20+ X 4, can I use united-chemi for the time being @ $5+ ea or Nichicon Audio caps 8.30ea? BTW these Aluminum Electrolytics, am I sourcing the correct capacitor type?

TIA
 
Last edited:
donberry said:
not an expert so take my answers with a grain of salt
1. I would use silver solder if possible. At least use silver bearing (radio shack)
2. I have not done that amp, but best not to remove the wires, leave them attached and carefully flip it. Some may break, if they do, then reattach by wrapping. may not be able to wrap as much due to the length now being shorter, but do the best you can.
3. buffer? extra parts? for the most part they are cheap so I always order extra just to have them on hand. Chances are you could just order exactly what is needed. Unless you put in a cap backwards, not that easy to mess one up
4. actually you can still use the 20% which is pretty typical. amp was designed with this in mind.
5. i forget the brand name , search "Newark filter caps" run about $28 a piece for 22,000uf.
6. you do not have to change resistors. I think it may be a good idea to check the ones on the amp boards, but chances are they are still good. Usually I believe if anything, the resistor value will actually rise. I was told it was not necessary, but as long as I had the amp boards out on my Spec 2 i replaced all the resistors with 1% metal film. Most would probably recommend putting in new pots, not really a have to item.
7. I would say NO.......if they ain't broke.....do not know what it uses, but probably not your garden variety output transistor......unless one is blown, leave those be.


just my 2 cents worth. I am sure you will get some more opinions and probably much better then mine
Click to expand...


Use 60/40 or whatever they sell for electronics nowadays. Silver solder I a LOT hotter and if your iron melts it, I would expect board damage.

Broken wrapped wires need to be soldered, wraps won't work without the correct specific tool. DO NOT UNWRAP!!!

everything else is fine...
 
markthefixer said:
Use 60/40 or whatever they sell for electronics nowadays. Silver solder I a LOT hotter and if your iron melts it, I would expect board damage.

Broken wrapped wires need to be soldered, wraps won't work without the correct specific tool. DO NOT UNWRAP!!!

everything else is fine...
Click to expand...

Thanks, MTF. Finally I was able to figure out how to remove one board (left channel). I de-soldered the header pins so there's no need to cut or un-wrap the wires, less mistake when putting it back. With that I was able to compare easily the caps actual values vs the similar SA8500ii SM that I have. Values in actual and SM seems identical (the ceramics a bit different unlike reading values of elcaps).

Next step is to source these parts getting the MPN's (Mfg P/N). I will post once the list is complete.

I am now getting excited. It's not that difficult as some may think, since this is dual mono, one board only consist of 13 caps. :yes:

BTW:

1.) I'm ok with 22000uf 50V oppose to the original part 10000uf 50V should be fine right? The filter caps dims is 45mm X76mm.

2.) Can I replace all the ceramics with mylar?

Jojo
 
First, only the electrolytic caps need to be replaced, ceramic and film caps do not deteriorate, electrolytics dry out. Tantalum caps get replaced too,

The rule of thumb is anything 1 microfarad or greater is almost always an electrolytic, with some exceptions in the 0.1uf to 1 uf range.

You are looking for caps with a can type construction with a rubber end seal.

Second, the manufacturer's numbers are almost certainly a dead end... all you need is the value in microfarads, the voltage rating, the physical configuration (axial(rare),radial(common)) and whether or not the capacitor is polarized.

Then post THOSE facts, or look through the posts where folks have already found similar caps.

Otherwise
Use Panasonic FC or FM, and Nichicon PW or HE.
digikey.com has panasonic and mouser.com has nichicon upw and uhe

EchoWars posted this:
For small value electrolytics (1µf - 100V
and under), I try to replace with a Panasonic stacked film cap. For non-polar
electro's, usually a Panasonic SU will do fine (if it is a non-polar axial, I
find a way to neatly incorporate a radial lead cap rather than resort to a
cheap speaker crossover-type electro).

When buying a radial lead cap, you are often given a choice between a short &
fat cap, or a tall & skinny one of the same value & voltage. The short & fat
one will have a longer life and better specs, and probably fit better in
vintage gear considering the reduction in size of electro's over the years.
Click to expand...
 
I removed the ceramics from the list, so I'm just down to 4 p/n's.

Here are the PN's sourced from Mouser. I used Nichicon PW's. Let me know if I did it right, so I can place the order. I suppose the HE and PW's are not available for the big caps.

C4 - 22uf 35V Nichicon # UPW1V220MDD
C5 - 330uF 6V Nichicon # UPW1C331MPD
C13 - 1uf 50V Nichicon # UPW1H010MDD
Filter caps 10000uf 50V Nichicon # LKS1H103MESC

The challenge was the filter caps, can't find one with a 40mm dia, largest I can find is 35mm, but should not be a problem placing spacers on the brackets.

Thanks again in advance.

Jojo
 
Remove and replace one cap at a time paying solid attention to polarity. Spend the money and get a decent desoldering iron of 30+ wattage or higher if available. A variable temp soldering iron will also make your life easier. Check MCM for some decent inexpensive units.
 
jojo0416 said:
I removed the ceramics from the list, so I'm just down to 4 p/n's.

Here are the PN's sourced from Mouser. I used Nichicon PW's. Let me know if I did it right, so I can place the order. I suppose the HE and PW's are not available for the big caps.

C4 - 22uf 35V Nichicon # UPW1V220MDD
C5 - 330uF 6V Nichicon # UPW1C331MPD
C13 - 1uf 50V Nichicon # UPW1H010MDD
Filter caps 10000uf 50V Nichicon # LKS1H103MESC

The challenge was the filter caps, can't find one with a 40mm dia, largest I can find is 35mm, but should not be a problem placing spacers on the brackets.

Thanks again in advance.

Jojo
Click to expand...

The first three are fine, the fourth is also fine, but I am unsure of the form factor and connections - so it's up to you.
 
Thanks King, that's exactly what I planned to do, I know what you mean with the iron, I both mine 2 months ago for this project @ 25watts, its taking forever to heat up. Yes, I will defenitely invest in a more decent one.

MTF, I studied the specs dimensions vs the actual, it should fit well, and the fourth I will work something out to fit the brackets. I am going to buy the parts on Tuesday, will keep you guys posted.

Thanks for all the suggestions and advises, you all have been a good help. :yes: I will be back with the results. :thmbsp:
 
I recommend that when you order the caps you also get a couple of rolls of fluxed desoldering braid. For me it works much better than a desoldering iron or other suction device.
 
Thanks Udors, I already placed the orders from Mouser this morning. I will let you guys know the moment I get the parts.

BTW, how do I test the actual value of the capacitors if its good in a DMM, I can remember in my electronic days the analog meter swings and goes back to zero?
 
To give update, the parts I ordered were shipped via USPS, until now have'nt received it yet and tracking result in USPS site is way too late.
While waiting I cleaned the board with Isoprophyl alcohol, I realized its a big NO NO, the alcohol reacted with the board's coating and left white residues, good thing the board is still ok.
 
going to have to clean the flux off the board (I use denatured alcohol) which will take the coating off anyway.
One thing I do is when i am done, to make it look pretty again, I clear coat the PCB board. If the board is out of the unit, I just spray it, if it is in the board, I spray into the cap and apply it with a small brush.
Can probably use about anything, I happen to use high heat (engine) clear I get from the autoparts store - maybe $6.00 a can which will do who knows how many boards.

Now some just leave it be as they do not wish to have to clean it off again if any more work is ever required. Me, I like the pretty looks. If I am doing a repair, I do make sure everything is operational before I do this.
You could always buy the stuff made for this purpose, but I have never had a problem with the clear I use and it looks like new again when I am done.
 
jojo0416 said:
To give update, the parts I ordered were shipped via USPS, until now have'nt received it yet and tracking result in USPS site is way too late.
While waiting I cleaned the board with Isoprophyl alcohol, I realized its a big NO NO, the alcohol reacted with the board's coating and left white residues, good thing the board is still ok.
Click to expand...

The white residue is a leftover element of the never cleaned off factory wave solder flux. A stiff brush (I use a paintbrush cut off to about 3/8 inch bristle) will clean it off as a powder. The stuff dissolves in the solvent, and surface tension when it's drying (water part, not alcohol part) forms microscopic balls instead of it drying adhered to the board. I see this when I use rubbing alcohol as a safer preliminary bulk cleaner.

I see the white residue a lot. The green coating stays on, and this is the first I have heard of clearcoating, which I do not recommend , the green solder mask does a perfectly adequate job.

I use acetone for cleaning and do not have any problems, INCLUDING the white residue - OTHER than being VERY CAREFUL I don't blow myself up. So far only the flux comes off, not the green solder mask.
 
Thanks, so the rubbing alcohol (70% Isoprophyl) is not such a bad move after all, it's good to know that the water made the reaction with the flux, and not alcohol with the green coating. I made a mistake before on using a lighter fluid with a brush to clean the board of my Denon amp, the magic smoke came out and blew the outputs. I don't know what went wrong, either I plugged it with the board not yet dry or I shorted something in the process.

The caps are now in New Jersey as of 8/8, I would probably get it within this week, so I can work on it in the weekend.
I removed the rust from the tranny and painted it with a black muffler paint, nothing compared to the experts here in AK but at least it looks better now.
 
Got the parts today and wasted no time in replacing the caps. I did not install the filters yet. I guessing the answer is yes given today's technology of smaller components but I need your expert opinion if for this case size does not matter. I have no problem in mounting as you can see in the 1 st picture. 2nd and 3rd are the before and after. I also cleaned and replaced the thermal compounds of the outputs.

Placed everything back, connected to my bookshelf PSB Alpha, powered it up....after a few minutes... man, there was a smile in my face, the sound was even better than before, I can't imagine just a few parts replacement can make a very big difference. :banana::banana::banana:

I am not good in describing but I can hear new instruments and the music seems to come alive :music: I am now listening to my Best Audiophile Voices Selection :D

Can't wait to complete the whole re-cap.

I also observed that the right outputs were already replaced, the left should be the originals: Below are the corresponding NEC#'s:

Right:
B617A / D588
B618 / D587A
Left:
B617A / D587A
B617A / D587A

Will the tone control section be the next best bet for re-cap?
I planning to also work on my SA9800II/SA9500 and SX1050 as my next project, if someone has a working Bill Of Materials of these 2, I hope you don't mind sharing, also trying to consolidate to save shipment cost.

Thanks in advance.

My special thanks to MTF, Kingbubba, Donberry, Udors giving me confidence and advises to start this project which I have been contemplating for the past 1.5 years.

Jojo
 

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I went ahead with the filter caps installation, and guess what? The pint size caps can do the job. :yes: Anyways, I found a Panasonic equivalent, on my next caps shopping I will get me another 4 set.
 

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I've made a moderate effort to locate the caps you got for replacement, and the nichicon number in the thread isn't stocked at mouser.

What caps are those in the picture and where did you get them?

And what about the other number you mentioned you intend to get?
 
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