• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Onkyo M-504 Recap

CohibaJoe

CohibaJoe

AK Subscriber
Subscriber
Just got in the amp...What a Nice amp. CL buy and 100%.

So what I am going to do...Recap this Beast.

Welcome to my Missile Silo..:D

The 8 Big cans are 9000uf /80v...

The Caps are a 4 Pin. I need to see how to use a 2 pin Snap-In.

I also am replacing the axial bulbs with LED's. Contacted a seller on fleebay..will be making these up.:yes:

All other caps will be Elna Silmic II

Will post back when I get these in..around 2-3 weeks..
 

Attachments

  • OnkyoM504b.jpg
    OnkyoM504b.jpg
    79.8 KB · Views: 747
  • OnkyoM504a.jpg
    OnkyoM504a.jpg
    120.7 KB · Views: 744
  • OnkyoM504Bulb.jpg
    OnkyoM504Bulb.jpg
    86.8 KB · Views: 650
Last edited:
Register to hide this ad
The person who is making the LED Axial lamps is now offering them on Fleebay(Seller: qua-co - Item number: 281049270499) :yes: This would be the way to go.

I should be getting this in by Tuesday. Once I install I will post some pictures.
 
Last edited:
I just had those big caps replaced on my 508...you might wanna look for a 100v cap, 80v is pretty close to rail voltage hich is part of the problem with them. My guy went with some caps from Chem Con..he also had to modify the pc board for fit due to leads being different and no longer avilable to the orginal ones. Those LEDs look sweet!
 
skinnypuppy said:
I just had those big caps replaced on my 508...you might wanna look for a 100v cap, 80v is pretty close to rail voltage hich is part of the problem with them. My guy went with some caps from Chem Con..he also had to modify the pc board for fit due to leads being different and no longer avilable to the orginal ones. Those LEDs look sweet!
Click to expand...
Yeh..I look forward getting the LED's.

I will look at 100v...I was thinking the same to increase to 100v. Only
one I see is United Chemi-Con ESMH101VND103MA63T. There is a Audio cap on fleebay...Sent a message to find out who makes it.
 
The speaker post are horrible. May as well replace those too but it get's a bit involved. Also the signal wire is long inside and could use a better cable to the rca's.
 
iceman79 said:
The speaker post are horrible. May as well replace those too but it get's a bit involved. Also the signal wire is long inside and could use a better cable to the rca's.
Click to expand...

Lord, ain't that the truth. Same kind on my Denon POA-1500. I can't stand 'em.
 
LED's Installed

Here you GO!!!!!:thmbsp:

LED's are in. These are 2-LED's per lamp. Again, search fleebay for "ONKYO AXIAL LAMP".

I used Lenght 1", Color Green and Volts 14.0 VDC(Onkyo)

I installed mine with LED side down at meter. I felt the brightness is just right.

Ordered the caps...till then..
 

Attachments

  • OnkyoM504LEDa.jpg
    OnkyoM504LEDa.jpg
    66.7 KB · Views: 550
  • OnkyoM504LEDb.jpg
    OnkyoM504LEDb.jpg
    68.6 KB · Views: 581
  • OnkyoM504LEDc.jpg
    OnkyoM504LEDc.jpg
    44.6 KB · Views: 460
  • OnkyoM504LEDd.jpg
    OnkyoM504LEDd.jpg
    30.6 KB · Views: 533
  • OnkyoM504LEDe.jpg
    OnkyoM504LEDe.jpg
    37.7 KB · Views: 541
Looking good:thmbsp: How much different do you think the led lighting is from the original? It appears to be very close to the same shade of green. Do you think it's any brighter?
 
motorstereo said:
Looking good:thmbsp: How much different do you think the led lighting is from the original? It appears to be very close to the same shade of green. Do you think it's any brighter?
Click to expand...

These look so good..I am never going back to incandescent bulbs.

I had two types of LED's made..2-LED and 4-LED. The 2-LED are a better match to the OLD bulbs. LED are softer to the eye and
even light thought out the meters. As the 4-LED..this will be Brighter and I am looking to get another M-504..so I will see then.

I say...rip the Old bulbs out and get into LEDS...:banana:
 
Hi...what is all involved in replacing the caps( just getting (8) new caps and installing them( as long as nothing else is wrong..or is there other things that has to be changed along with doing that?
 
Nice! My tech also changed my M-504 bulbs to LED last Jan., I can' tell the difference from the original. :thmbsp:
I will take a peek later tonight if he used 2 or 4
 
I'm just curious, cohibajoe,

This amp is around, what...20 years old?? Does it necessarily NEED a recap?

Just asking. I have so much stuff that needs attention...mine works 100% (balance knob is assy, tho...) and still attempting to have a functioning Pioneer SX-1250 (oh, the headaches..)
 
onwardjames said:
I'm just curious, cohibajoe,

This amp is around, what...20 years old?? Does it necessarily NEED a recap?

Just asking. I have so much stuff that needs attention...mine works 100% (balance knob is assy, tho...) and still attempting to have a functioning Pioneer SX-1250 (oh, the headaches..)
Click to expand...

Well, 20 year old caps are likely near or at their service life. Recapping is a reliability measure in some respects. With an upgrade in voltage and possibly capacitance, you may even get enhanced performance. At the very least, if one is trying to get full power for sustained periods of time, the caps will not be a worry.

So CohibaJoe, did you ever complete your restoration?
 
onwardjames said:
I'm just curious, cohibajoe,

This amp is around, what...20 years old?? Does it necessarily NEED a recap?

Just asking. I have so much stuff that needs attention...mine works 100% (balance knob is assy, tho...) and still attempting to have a functioning Pioneer SX-1250 (oh, the headaches..)
Click to expand...
As "mech986" said..For reliability I would. I have been running the M-504 since Friday as I changed out the 2 Nichicon FG I had on the Amp Board with Elna Silmic II. YES...As I also said many times...The Silmic II have a MORE defined Bass thru Smooth Highs.
mech986 said:
Well, 20 year old caps are likely near or at their service life. Recapping is a reliability measure in some respects. With an upgrade in voltage and possibly capacitance, you may even get enhanced performance. At the very least, if one is trying to get full power for sustained periods of time, the caps will not be a worry.

So CohibaJoe, did you ever complete your restoration?
Click to expand...
The only item I DID NOT change are the Main Caps. Issue is the 4 Pins on the Orig Caps. New ones I just got in from Mouser (Cornell Dubilier 380XL) are 2 Pin. I am going to make a Shout Out to see if anyone had installed to see what Mods was added.

Sound Wise...With the Caps update and the P-304 Op-Amp update (another thread)...I just may leave these alone for now(Hum...:no:)..well just for a little while.
 
OK...MAKING A SHOUT OUT!!!!

Has anyone changed the Main Caps for the M-504 ?

Need to break out the SM for pin outs.

As you can see with the Pic...4 Pins on Orig Cap...as to 2 Pins for replacement.
 

Attachments

  • OnkyoM504g.jpg
    OnkyoM504g.jpg
    133.5 KB · Views: 408
I think I read a thread on AK a while back about someone doing this exact cap change out. It was on either a M-504 or M-508. I don't remember the details, but it took some re-engineering because of the dual capacitor original design. I would search for the post, but I will be away to do other things much of today. So it's doable, just not straight-forward maybe??
 
Hmmm, missed this thread.

I've done filter cap replacement pm a 504 and 508 and it is NOT simple DIY. The geniuses at Onkyo used caps with 4 pins. Nothing special, just a U bar on the cap. I've seen them in other things. BUT, they designed the circuit board to use the pins separately and the caps are installed through hole. SO, replacing with 2 pin types means reconnecting all the separate traces. The closest size are (were) snap in where you need to cut off the extra pins. AND the new pins are damn short AND spaced different, so you need to re-drill the circuit board. The new holes are so close to the sub chassis that it made me nervous about shorts, so I machine the sub chassis away from the new pin locations.

The original connections are large pieces of copper plate with a lot of solder. All that must be removed (LARGE solder iron) and they won't fit back on the new caps.
So you need to build new connectors.

I made copper jumpers for the board traces using the old holes and soldered them in and then built copper busses from heavy wire across the cap pins. I even added solder wick to help flow all the new solder points well. Lots of hot solder.

I think the next time, I would look to a different solution. Like adding a sub-sub chassis and board and using point-to-point wiring.
 
blhagstrom said:
Hmmm, missed this thread.

I've done filter cap replacement pm a 504 and 508 and it is NOT simple DIY. The geniuses at Onkyo used caps with 4 pins. Nothing special, just a U bar on the cap. I've seen them in other things. BUT, they designed the circuit board to use the pins separately and the caps are installed through hole. SO, replacing with 2 pin types means reconnecting all the separate traces. The closest size are (were) snap in where you need to cut off the extra pins. AND the new pins are damn short AND spaced different, so you need to re-drill the circuit board. The new holes are so close to the sub chassis that it made me nervous about shorts, so I machine the sub chassis away from the new pin locations.

The original connections are large pieces of copper plate with a lot of solder. All that must be removed (LARGE solder iron) and they won't fit back on the new caps.
So you need to build new connectors.

I made copper jumpers for the board traces using the old holes and soldered them in and then built copper busses from heavy wire across the cap pins. I even added solder wick to help flow all the new solder points well. Lots of hot solder.

I think the next time, I would look to a different solution. Like adding a sub-sub chassis and board and using point-to-point wiring.
Click to expand...

This is why someday YOU will be getting my amp. You really care about your work and don't look for shortcuts. You think through everything taking into account all things that may pose a future problem
 
The caps pictured don't look like double caps...was this a running change or have they already been replaced by someone, making a bank of eight instead of 4 doubles?
 
You must log in or register to reply here.
Back
Top Bottom