Pioneer SPEC-4 repair and restoration thread!

[petervv]

All,

Thanks for the compliments!

>What happened with your relay to transformer clearances?
>I have a spec-4 that had the caps and relay rammed into the chassis/transformer...

The Omron MY-02 is a tight fit in my case, I've got maybe 1mm of air.

>not many original parts left...

Indeed, just the connectors, bias diodes (all were intact!) thermistors and off course the inductor, see picture.

>No ceramics----EXCELLENT!

I replaced all with MKP or Mica, not for reliability but for sound.
Also replaced the Polyester caps with MKP, I don´t want to start a thread about the sound of capacitors, but ceramics and polyester are ´not done´ in high end audio, and it´s a very small extra investment.....

Has anyone ever searched for a replacement for the mains relays and found something suitable?

Next project will be a PL630 with just about all electronics problems I could find in the various PL630 threads.

regards, Peter

 

[omri617]

Why did you leave D2 + D3 ?
And TH1 + TH2 thermistors?

 

[markthefixer]

Why did you leave D2 + D3 ?
And TH1 + TH2 thermistors?

Simple, those parts can no longer be sourced, they are unique. Just like the heat sinks, the coil and the connectors.

I will be on the mains relay soon enough, with several spec-4's waiting for attention.

If there is just one relay, it's a model KU (120v only) using Pioneer parts number asr-041, a 120vac relay (dpdt?) and being a chassis mount with lower ears, that is wired in, there are few constraints on it.\
This MIGHT be ok, according to the schematic :653-LY1F-AC1 as it shows a SPST normally open relay.


However the model S is the 110-120-220-240 using dual asr-044 relays. They are both chassis mount with ears, and I could see no normally closed (clipped) contacts, but I could maybe see double poles, I could not open them to check.

I suspect they both can be:mouser.com's
653-LY2F-AC1 - a DPDT relay - this should help you find equivalents.
mounted with four standoffs.

This post Pioneer SX-1010, 939, 838, et.al., Relay Replacement gets you a head start as to the relays with ears - at the TOP (sadly) and what is done to compensate.

p.s Where did you get the beads to raise the resistors? not all needed to be raised, especially if they were flameproof resistors, which their color seems to indicate they are.
also I realize that ceramic caps are not for passing quality audio, but I usually thought they were fine for bypassing HF.

 

[petervv]

hi Mark,

The relay you propose looks like a drop in replacement, unfortunately I didn't research long enough and have already ordered other relays. These are PCB type relays and will need a small board, I think it will look ok, I'll post the results.

I also found this thread on the subject: http://www.audiokarma.org/forums/archive/index.php/t-367581.html

>However the model S is the 110-120-220-240 using dual asr-044 relays

I indeed have the S model, even the model with the thermal fuses inside the transformers, which are in series with the incoming mains.

>p.s Where did you get the beads to raise the resistors?

actually, I found them in a drawer at work..., I did look if I could buy them at Mouser/Farnell but couldn't find them.

>not all needed to be raised

I raised all that had a sleeve (on one of my boards)

>especially if they were flameproof resistors, which their color seems to indicate they are.

they are not flameproof, standard KOA Speer from Mouser, I looked at the flame proof version but couldn't find all values I needed.

>>also I realize that ceramic caps are not for passing quality audio, but I usually thought they were fine for bypassing HF.

Ceramics are non-linear and therefore introduce distorsion, you can find some info here http://sound.westhost.com/articles/capacitors.htm#2.4.
I don't know if it's the ceramics but the SPEC-4 sounds a lot better (smoother, more musical) then my recapped SA-9500II I was using as a power amp up till now.

I have a shoot out planned with some friends, we will be comparing the SPEC-4 against Odyssey Audio Stratos Mono amps and Hypex nCore 400, driving Magnepan MG1.6 speakers.

regards, Peter

 

[markthefixer]

I have found improvements when all main caps are bypassed by 2.2uf (or 1uf) stacked film capacitors, that smoothness, regardless of model. On the higher end stuff, there are ceramic bypass caps across the power filter electrolytics in the amplifiers. So they (pioneer's engineers) did have an inkling of the problem. Of course I go for stacked film caps there too.

 

[petervv]

The new mains relays are in, problem solved, I used these: http://nl.farnell.com/te-connectivity-schrack/7-1393243-8/relay-power-pcb-115vdc-8a/dp/2060849, had already ordered them when Mark suggested the LY2F.

I'm not too proud of the install, I should have made the board a bit larger than the hole in the chassis, would have looked better. Next time I'll use the LY2F.

All the wire-wrap connections on the fuse board were soldered, somebody before me had been trying to fix the problem but didn't succeed.

regards, Peter

 

[markthefixer]

I just finally found the mouser number for the standoffs, for the LY relays

from my notes:
24v dc dpdt chassis mount using upper ears 24v 653-LY2F-DC24 MOUSER.COM stock level 51 @ $ 6.55
being chassis mount, conversion from doubled 4pdt to dpdt is easy
standoff from mouser 15mm need two per side: 728-FM2110-3005-A due to TOP ears!!
728-FM2110-3005-A is 4.5mm od 3mm x 0.5 thread 15mm male female aluminum 0.63 /100: 0.43
728-FM2110-3005-SS is 4.5mm od 3mm x 0.5 thread 15mm male female stainless steel 1.07 /100: 0.74
728-FM1262-3005-A is 4.5mm od 3mm x 0.5 thread 15mm female female aluminum 0.59 /100: 0.40
728-FM1262-3005-SS is 4.5mm od 3mm x 0.5 thread 15mm female female stainless steel 0.97 /100: 0.67

I am leaning toward using one male/female and one double female, leaving female threaded holes in both ends of the stand offs, due to the difficulty I had getting the 3mm threads of the males into a sx-1010's 3mm threaded chassis holes, and the lack of 3mm threaded 30mm long standoffs.
So
I enlarged the holes to 3mm clearance and used 3mm x 0.5 steel screws instead on both ends.


Considering yours:
All things considered ( I wouldn't let those relay mounts bother me much) a great job. :yes:

 

[omri617]

I'm sorry but the list is a bit not organized , is this the correct BOM list ? :

647-UPW2A101MHD | 1
647-UPW1V101MPD | 1


647-UKL1H2R2KDDANA | 1
647-UPW1H2R2MDD | 4
647-UPW1A221MED | 1
647-UPW1A471MPD | 4
647-UPW2A3R3MDD | 2
647-UPW2A470MPD6 | 2
647-UPW2A331MHD | 2
647-UPW1V330MDD | 1
647-UPW1V470MED | 5
647-UPW1H3R3MDD | 2
647-UPW2A470MPD6 | 1
647-UPW2A101MHD | 8
667-ECQ-V1H224JL | 2
512-KSC1845FTA | 4
512-KSC2383YTA | 2
512-KSC945CYTA | 2
512-KSC2690AYS | 1
512-KSD1616AGBU | 2
653-MY2-02-DC48 | 2
652-3386H-1-501LF | 2
652-3296P-1-501LF | 2


512-KSA1013YBU | 2
512-KSC945CYTA | 2
512-KSC3503DSTU | 1
512-KSA1381ESTU | 1
512-KSC2073TU | 1
512-KSA940TU | 1
863-MJ21194G | 4
863-MJ21193G | 4
660-MF1/4DCT52R22R0F | 1
660-MF1/2CCT52R2000F | 1
660-MF1/2LCT52R221J | 1
660-MF1/2DCT52R1000F | 1

 

[vsat88]

Sorry as I am a NooB. I have a few questions.

1st. what does BOM stand for ?
2nd. I see a parts list but where do I order from Mouser Digikey or some from both ?
3rd. Can I get original light bulbs and if so where please.

I am just trying to get one up and running (SPEC 4) and I will decide if I going for the full re build after that. I know I have bad output transistors on one channel and a bad driver transistors as well as bad resistors and diodes on the same channel. I intend on replacing all the parts on both boards including output TX and the driver TX on both channels then on to other parts in the amp. I know about the dim bulb tester and I have a veriac. With regards, Jim H.
Oh BTW. if someone really wants to make it easy on me please send me a complete parts list of what I need to re build both output boards and where I should buy them. I would like to go back completely stock if possible Thanks, Jim H.

 

[markthefixer]

Any further exploration of this matter really deserves it's own thread please.

OK, here goes:

Bill of materials in the service manual.
Our defacto "BOM list" is a text block that can be cut and pasted into mouser.com's parts list importer tool (free registration required)

The bulkier part of the list preceeding the text block shows the board number and specific component referenced.

The "BOM list" is an extraction of just the mouser parts numbers from this list.

They are mouser part numbers

AK's own dgwojo is the lamp guru

master list of lists

from the spec-4 listed thread:

Thanks Tim. Here is the recap list for the SPEC-4.

Pioneer SPEC-4 recap list

Meter Amp Board (AWM-113) (Q8 and 9 should be gain matched) (Check board revision number, the A version has C1 as a 100uF 25v CEA cap and C11 as a 100uF 80v CEA cap)

AWM-113: C1: 220uF 10v CEA: 647-UPW1A221MED 220uF 10v
AWM-113: C2: 2.2uF 50v CEANL: 647-UKL1H2R2KDDANA 2.2uF 50v
AWM-113: C3: 470uF 6.3v CEA: 647-UPW1A471MPD 470uF 10v
AWM-113: C4: 470uF 6.3v CEA: 647-UPW1A471MPD 470uF 10v
AWM-113: C7: 3.3uF 63v CEA: 647-UPW2A3R3MDD 3.3uF 100v
AWM-113: C8: 3.3uF 63v CEA: 647-UPW2A3R3MDD 3.3uF 100v
AWM-113: C11: 47uF 80v CEA: 647-UPW2A470MPD6 47uF 100v
AWM-113: C12: 47uF 80v CEA: 647-UPW2A470MPD6 47uF 100v
AWM-113: C13: 330uF 100v CEA: 647-UPW2A331MHD 330uF 100v
AWM-113: C14: 330uF 100v CEA: 647-UPW2A331MHD 330uF 100v
AWM-113: C16: 33uF 25v CEA: 647-UPW1V330MDD 33uF 35v
AWM-113: C17: 47uF 16v CEA: 647-UPW1V470MED 47uF 35v
AWM-113: C18: 470uF 6.3v CEA: 647-UPW1A471MPD 470uF 10v
AWM-113: C19: 470uF 6.3v CEA: 647-UPW1A471MPD 470uF 10v
AWM-113: C24: 2.2uF 50v CEA: 647-UPW1H2R2MDD 2.2uF 50v
AWM-113: C25: 2.2uF 50v CEA: 647-UPW1H2R2MDD 2.2uF 50v
AWM-113: C26: 2.2uF 50v CEA: 647-UPW1H2R2MDD 2.2uF 50v
AWM-113: C27: 2.2uF 50v CEA: 647-UPW1H2R2MDD 2.2uF 50v
AWM-113: C28: 3.3uF 50v CEA: 647-UPW1H3R3MDD 3.3uF 50v
AWM-113: C29: 3.3uF 50v CEA: 647-UPW1H3R3MDD 3.3uF 50v
AWM-113: C30: 47uF 16v CEA: 647-UPW1V470MED 47uF 35v
AWM-113: C31: 47uF 16v CEA: 647-UPW1V470MED 47uF 35v
AWM-113: C32: 47uF 25v CEA: 647-UPW1V470MED 47uF 35v
AWM-113: C33: 47uF 25v CEA: 647-UPW1V470MED 47uF 35v

Q8: 2SC945: 512-KSC945CYTA
Q9: 2SC945: 512-KSC945CYTA
Q11: 2SC945: 512-KSD1616AGBU
Q12: 2SC945: 512-KSD1616AGBU
Q13: 2SC1384: 512-KSC2690AYS

If board is the "A" revision, then:

Q1: 100uF 25v CEA: 647-UPW1V101MPD 100uF 35v
Q11: 100uF 80v CEA: 647-UPW2A101MHD 100uF 100v

BOM List, put the 647-UPW2A470MPD6 to 1 and add these two lines into the main BOM list:

647-UPW2A101MHD | 1
647-UPW1V101MPD | 1

Power Amp Board (AWH-065) (Times 2) (Q2 and 3 should be gain matched)

AWH-065: C1: 100uF 80v CEA: 647-UPW2A101MHD 100uF 100v
AWH-065: C2: 100uF 80v CEA: 647-UPW2A101MHD 100uF 100v
AWH-065: C3: 100uF 80v CEA: 647-UPW2A101MHD 100uF 100v
AWH-065: C4: 100uF 80v CEA: 647-UPW2A101MHD 100uF 100v
AWH-065: C24: .22uF 10v CSSA: 667-ECQ-V1H224JL .22uF 50v

Q2: 2SC1775: 512-KSC1845FTA
Q3: 2SC1775: 512-KSC1845FTA
Q12: 2SC869: 512-KSC2383YTA

VR1: 470 ohm multi offset: 652-3296P-1-501LF 25 turn
VR2: 470 ohm single bias: 652-3386H-1-501LF 1 turn

Only replace these VR's below if you have the equipment to re-adjust the power limiter after replacement:

VR3: 100 ohm single: 652-3386H-1-101LF
VR4: 100 ohm single: 652-3386H-1-101LF

S1: MU2U 48VDC relay: 653-MY2-02-DC48

BOM List:

647-UKL1H2R2KDDANA | 1
647-UPW1H2R2MDD | 4
647-UPW1A221MED | 1
647-UPW1A471MPD | 4
647-UPW2A3R3MDD | 2
647-UPW2A470MPD6 | 2
647-UPW2A331MHD | 2
647-UPW1V330MDD | 1
647-UPW1V470MED | 5
647-UPW1H3R3MDD | 2
647-UPW2A470MPD6 | 1
647-UPW2A101MHD | 8
667-ECQ-V1H224JL | 2
512-KSC1845FTA | 4
512-KSC2383YTA | 2
512-KSC945CYTA | 2
512-KSC2690AYS | 1
512-KSD1616AGBU | 2
653-MY2-02-DC48 | 2
652-3386H-1-501LF | 2
652-3296P-1-501LF | 2

And the additional list for the blown components on the right amp board:

Power Amp Board (AWH-065)

Q6: 2SA733: 512-KSA1013YBU
Q7: 2SC945: 512-KSC2383yta
Q8: 2SC1904: 512-KSC3503DSTU
Q9: 2SA899: 512-KSA1381ESTU
Q10: 2SD608: 512-KSC2073TU
Q11: 2SB628: 512-KSA940TU
Q13: 2SC945: 512-KSC2383yta
Q14: 2SA733: 512-KSA1013YBU

R24: 22 ohm 1/4w: 660-MF1/4DCT52R22R0F 22 ohm 1/4w
R28: 200 ohm 1/2w: 660-MF1/2CCT52R2000F 200 ohm 1/2w
R34: 220 ohm 1/2w: 660-MF1/2LCT52R221J 220 ohm 1/2w
R36: 100 ohm 1/2w: 660-MF1/2DCT52R1000F 100 ohm 1/2w

The outputs

2SD424: 863-MJ21194G
2SB554: 863-MJ21193G

BOM list

512-KSA1013YBU | 2
512-KSC2383yta | 2
512-KSC3503DSTU | 1
512-KSA1381ESTU | 1
512-KSC2073TU | 1
512-KSA940TU | 1
863-MJ21194G | 4
863-MJ21193G | 4
660-MF1/4DCT52R22R0F | 1
660-MF1/2CCT52R2000F | 1
660-MF1/2LCT52R221J | 1
660-MF1/2DCT52R1000F | 1

All parts were confirmed to be in stock at the time of this post.

Does this cover all your needed transistors?

 

[omri617]

Mark your posts are just extraordinary!

 

[vsat88]

This is unbelievable ! Now I know (I think) what to do. It pretty much makes sense now. I do have the original schematic from Pioneer that came with the amp so that will come in handy. I suppose as far as outputs and driver TX. I order X 2... And lastly, Please tell me the etiquette Markthefixer am I the one who should start another thread if so I am more that willing to do so and I thank all the above for your help !

 

[markthefixer]

Yes, please start your own thread if you have more questions.

 

[jackflack]

EchoWars,

Did you ever start another thread on how you did this?

Spec 4 Relay Swap

Wanted to do a swap as neatly as possible with an Omron MY2. I think this worked out OK.

I have another channel to do, and I'll document it and start another thread.

 

[EchoWars]

I didn't. Sometimes I just get into the moment and forget that I wanted to document it.

Sorry about that. I don't see a lot of Spec 4's and should have followed up.

 

[IMF_Pioneer]

Hi Peter,

Just going back to the two photos of both your amp boards a some posts back now,

Am I correct in saying that the two Amp boards are from totally different units as the KU variant has 2 capacitors on the lower area of each side of the board while the S and G Models only have 1 cap on each side ?

 

[vsat88]

IMF, I was partly involved in the above thread but the last time someone commented was in or around September 2016 as far as I can tell so this is a pretty old thread. I am unsure what you mean by your above post but I wanted to let you know that there is someone still here following. Hopefully someone can help and answer your questions.

 

[zebulon1]

Best to start your own thread.
Click here for a shortcut

 

[zebulon1]

Hey, I am working on this Spec 4. It's the first one I've done.
I was following the speaker relay mods posted here in the thread and want'ed to add my tool I made to align the holes for the S1 relay 653-MY2-02-DC48 and the outcome.
I hope this adds to this already informative thread.
Nothing fancy, a hole alignment tool to get the exact position of the relay pins. Clear so you can see the traces and lead holes. Note: The two lower holes on the make shift jig that look off are not used. And, don't drill a hole in your finger while mod'ing the board

 

[embrown057]

The SPEC-4 talk has been light, not as popular as the SPEC-2. That's a shame since this amp has great detail and enough power for a lot of great speakers. Just to add some detail pictures of what can be done. This unit has been in service with the customer for 5 months now. Without any wildly absurd embellishment, he loves it. Sure it's over the top but it was well worth it.