Hi, I used the 2SC2632 in my black SU-V8. These parts are well gone, and though they appear on sites like yahoo auctions, the shipping is high, and then its not known if they are real or hot, though some looked really like the old parts My silver SU-V8 is now in need of replacements.
Following a bit of search around DIYAudio forums, i came up with 2 possible replacements. I can only get D version in the KSC series, frequency is the same not the Hfe
KSA1381ESTU
https://au.mouser.com/datasheet/2/308/1/KSA1381_D-1810601.pdf
KSC3503DSTU
however the matching pair is D spec not E (which appears to be discontinued)
https://www.onsemi.com/pdf/datasheet/ksc3503-d.pdf
So that concerns me re the specs, though both have good frequency like the old
I got another pair of transitors also
2N5551 PBFREE/ 2N5401 PBFREE
https://my.centralsemi.com/datasheets/2N5550_2N5551.PDF
https://au.mouser.com/datasheet/2/68/2n5400_5401-1518545.pdf
Old parts
https://alltransistors.com/adv/pdfview.php?doc=2sc2632.pdf&dire=_panasonic
Thanks
Sam
I have the above from my order from Mouser, just not sure which is best
@Iomis Hi Cosmin, its Sam, you may remember me, i think you said you had a Technics SU-V8, did you need to change your transistors, ones above i have from my order
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Hello, Sam,
Of course I remember you.
I don't use my SU-V8 anymore, but I'll open her tonight (it's 5 AM here now) and let you know what transistors I used. Can't remember if I changed them. Anyway, I bought some 1381E/3503E from our colleague here and they substituted those 1123/2631 and 1124/2632 just fine. Years ago I bought a few pairs of 1124/2632 from the Japanese site you mentioned and they were OK.
Best regards, stay in touch,
Cosmin
Of course I remember you.
I don't use my SU-V8 anymore, but I'll open her tonight (it's 5 AM here now) and let you know what transistors I used. Can't remember if I changed them. Anyway, I bought some 1381E/3503E from our colleague here and they substituted those 1123/2631 and 1124/2632 just fine. Years ago I bought a few pairs of 1124/2632 from the Japanese site you mentioned and they were OK.
Best regards, stay in touch,
Cosmin
Good morning Cosmin,
Thank you, here is 12:46pm, so lunch time here. Thanks for the link. Yahoo auctions have them now and then the transistors. I have my silver V8 dismantled, and adding new internal wiring and cleaning up the cabinet. I replaced the small electro capacitors. My black SU-V8, its almost ready to do the bias.
Best Regards, and have a nice day
Sam
Thank you, here is 12:46pm, so lunch time here. Thanks for the link. Yahoo auctions have them now and then the transistors. I have my silver V8 dismantled, and adding new internal wiring and cleaning up the cabinet. I replaced the small electro capacitors. My black SU-V8, its almost ready to do the bias.
Best Regards, and have a nice day
Sam
Thank you Wiseoldtech, good news they work fine afterwards. Ones i have, not sure of.
Hi, Sam,
Just opened the amp and... surprise! I used TTA/TTC004B! I really don't remember what was the reason at that time. Probably something like 'how about...?'. Although not needed, I attached to them something like this (they're used to attach a power device to heatsink). Because of their shape, they go sideways and make no contact with the lid above.
The amplifier plays fine and I remember she looks great on oscilloscope (including unnecessary square wave tests). I don't have an analyser, nor external soundcard for in-depth tests.
Also, 4 blue capacitors found their way in the power supplies, replacing initial attempt with 15000uF/63v Mundorfs (they don't have the right pin-out, and I felt somehow uncomfortable with that).
Best regards,Cosmin
PS: Hmmm, those screws are inappropriate...
Just opened the amp and... surprise! I used TTA/TTC004B! I really don't remember what was the reason at that time. Probably something like 'how about...?'. Although not needed, I attached to them something like this (they're used to attach a power device to heatsink). Because of their shape, they go sideways and make no contact with the lid above.
The amplifier plays fine and I remember she looks great on oscilloscope (including unnecessary square wave tests). I don't have an analyser, nor external soundcard for in-depth tests.
Also, 4 blue capacitors found their way in the power supplies, replacing initial attempt with 15000uF/63v Mundorfs (they don't have the right pin-out, and I felt somehow uncomfortable with that).
Best regards,Cosmin
PS: Hmmm, those screws are inappropriate...
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Hi Cosmin,
I almost got the Toshibas. There is not much room in height with the V8s ICQ pcb, so that gives me an idea how to heatsink them, as i think they do run hot there. I may ditch the ones i have for the toshiba you got, since the v8 is running so well on the oscilloscope. These main caps are the same height and widith of the old. -https://www.digikey.com.au/en/produ...lier-electronics-cde/382LX123M080A082/2295338 The CDE seem to be popular replacements as well as the KMH/SMH UCC. Did you need to change the emitter or diodes with the extra 2000uf increase?
Best Regards
Sam
I almost got the Toshibas. There is not much room in height with the V8s ICQ pcb, so that gives me an idea how to heatsink them, as i think they do run hot there. I may ditch the ones i have for the toshiba you got, since the v8 is running so well on the oscilloscope. These main caps are the same height and widith of the old. -https://www.digikey.com.au/en/produ...lier-electronics-cde/382LX123M080A082/2295338 The CDE seem to be popular replacements as well as the KMH/SMH UCC. Did you need to change the emitter or diodes with the extra 2000uf increase?
Best Regards
Sam
Hello,
There's no need to heatsink that type of capsule.
Now that you mentioned, I took a look over the rectifier diodes and they are MUR420. Geee! Nowadays I wouldn't change them. The extra 5000uF from former Mundorfs didn't hurt, so your option for reservoir caps is fine. I must mention that the original electrolitycs measured perfect a few minutes ago. Man, there's plenty of 'upgrades' I wouldn't do today.
I read somewhere that Cornell-Dubilier bought some Panasonic facility/research center in the U.S. years ago... and I was under the impression that newer CDE 383/382LX series are former T-HA and T-UP series from Panasonic. I'm probably wrong, but this is the reason for I'm inclined to use the American brand.
As you can see, my English is not OK, so I don't know what you mean by 'emitter' in that context.
The only modification I'd do at my actual (sooo limited) knowledge would be at transformer(s) level. I'm convinced that bigger (in Ampere terms) is definitely better. And I think I saw a photo with toroidals inside an SU-V8. Anyway, my point is that this model is designed well enough then for what it has to offer. And was top of line! (I understand why a plane or a ship is reffered to as 'she/her' but why an amplifier?) I also do not disagree with people trying to upgrade here and there, this is a way to learn stuff.
Best regards,
Cosmin
There's no need to heatsink that type of capsule.
Now that you mentioned, I took a look over the rectifier diodes and they are MUR420. Geee! Nowadays I wouldn't change them. The extra 5000uF from former Mundorfs didn't hurt, so your option for reservoir caps is fine. I must mention that the original electrolitycs measured perfect a few minutes ago. Man, there's plenty of 'upgrades' I wouldn't do today.
I read somewhere that Cornell-Dubilier bought some Panasonic facility/research center in the U.S. years ago... and I was under the impression that newer CDE 383/382LX series are former T-HA and T-UP series from Panasonic. I'm probably wrong, but this is the reason for I'm inclined to use the American brand.
As you can see, my English is not OK, so I don't know what you mean by 'emitter' in that context.
The only modification I'd do at my actual (sooo limited) knowledge would be at transformer(s) level. I'm convinced that bigger (in Ampere terms) is definitely better. And I think I saw a photo with toroidals inside an SU-V8. Anyway, my point is that this model is designed well enough then for what it has to offer. And was top of line! (I understand why a plane or a ship is reffered to as 'she/her' but why an amplifier?) I also do not disagree with people trying to upgrade here and there, this is a way to learn stuff.
Best regards,
Cosmin
Hello Cosmin,
I didnt know the term emitter resistor at first either. It is those large white cement type near the output transmitters. I think your english is great, and i believe is one of the most difficult languages to learn. Thanks, i can get your sort of heatsink at Mouser, i found them last night, they call them heatsink clips.
The 420 rectifier diodes, are 4A verse the original at 3A. The old reservoir caps seem to have a high tolerance -20/+80%, so this may allow an extra 5000uf over the original 10000uf capacitors. Did you get a chance to measure the old capacitors? I only replaced the small electrolitycs in mine after finding one bad one with a leaking leg. However, that is amazing they still measured perfectly, I wonder if the new replacements could last as long as the original capacitors - I think not.
That is interesting about Cornell-Dubilier buying some Panasonic research facility. The series 383/2 are the former T-HA and T-UP series. It could be possible, as i know Panasonic seem to have stopped production of certain components like power relays etc. The only audio line they have now is Technics, however i could be wrong. Alot of people on another forum and here seem to like United Chem Con KMH/SMH capacitors, however they are not regularly stocked.
I saw that Technics SU-V8 on youtube with 2 toroidals inside. If you wanted more Ampere, the toroidals are good in terms of noise etc? The V8 was the top of the line, before the V9. The chassis of the V8 is better constructed than the SU-V9 - it's built like a tank. I call my audio gear she or her also, and name them, for instance the V8s are Dustinator ( black SU-V8) and Bourbonette (silver SU-V8) haha
Best Regards Sam
p.s the main capacitors without the plastic cases in my silver SU-V8 amplifier. I was assured by another friend , they will be fine, even though I did scratch two of them. Since she still sounds good, i may keep them, Reason i removed the sleeve was the tops looked bulged, however this was only the plastic cap, they look perfect otherwise. They large white resistors are the emitter resistors. I think over the years the heat may cause the plastic top to warp.
I didnt know the term emitter resistor at first either. It is those large white cement type near the output transmitters. I think your english is great, and i believe is one of the most difficult languages to learn. Thanks, i can get your sort of heatsink at Mouser, i found them last night, they call them heatsink clips.
The 420 rectifier diodes, are 4A verse the original at 3A. The old reservoir caps seem to have a high tolerance -20/+80%, so this may allow an extra 5000uf over the original 10000uf capacitors. Did you get a chance to measure the old capacitors? I only replaced the small electrolitycs in mine after finding one bad one with a leaking leg. However, that is amazing they still measured perfectly, I wonder if the new replacements could last as long as the original capacitors - I think not.
That is interesting about Cornell-Dubilier buying some Panasonic research facility. The series 383/2 are the former T-HA and T-UP series. It could be possible, as i know Panasonic seem to have stopped production of certain components like power relays etc. The only audio line they have now is Technics, however i could be wrong. Alot of people on another forum and here seem to like United Chem Con KMH/SMH capacitors, however they are not regularly stocked.
I saw that Technics SU-V8 on youtube with 2 toroidals inside. If you wanted more Ampere, the toroidals are good in terms of noise etc? The V8 was the top of the line, before the V9. The chassis of the V8 is better constructed than the SU-V9 - it's built like a tank. I call my audio gear she or her also, and name them, for instance the V8s are Dustinator ( black SU-V8) and Bourbonette (silver SU-V8) haha
Best Regards Sam
p.s the main capacitors without the plastic cases in my silver SU-V8 amplifier. I was assured by another friend , they will be fine, even though I did scratch two of them. Since she still sounds good, i may keep them, Reason i removed the sleeve was the tops looked bulged, however this was only the plastic cap, they look perfect otherwise. They large white resistors are the emitter resistors. I think over the years the heat may cause the plastic top to warp.
Hi,
The original electrolytics measured over 9800uF with an ESR of 0.04Ohms (@120Hz)..
The emitter resistors will not be affected if you increase the capacitance of those filter electrolytics (you can read this topic).
Changing transformers in your SU-V8 is not worthing the cost, as they'll have to be custom made (I paid 1 year ago for a 321VA toroidal - 4x20V/4A + 12V/0.1A and screening between primary and secondaries - over 100 Euros, so 2x over 500VA made for audio use...). Anyway, I don't think there's much to improve in this design.
Remember, my posts represent my opinions and you'd not take them as an absolute truth.
This topic you started is about some transistor equivalencies and you've been presented a few options... Repair The Dustinator and start making your own amplifier, there's plenty of them to try. Buy a kit... then another... and maybe, at some point, you'll present your own personal project. Or try other brands, other concepts, if you think that SU-V8 isn't what you want.
Good luck, best wishes,
Cosmin
The original electrolytics measured over 9800uF with an ESR of 0.04Ohms (@120Hz)..
The emitter resistors will not be affected if you increase the capacitance of those filter electrolytics (you can read this topic).
Changing transformers in your SU-V8 is not worthing the cost, as they'll have to be custom made (I paid 1 year ago for a 321VA toroidal - 4x20V/4A + 12V/0.1A and screening between primary and secondaries - over 100 Euros, so 2x over 500VA made for audio use...). Anyway, I don't think there's much to improve in this design.
Remember, my posts represent my opinions and you'd not take them as an absolute truth.
This topic you started is about some transistor equivalencies and you've been presented a few options... Repair The Dustinator and start making your own amplifier, there's plenty of them to try. Buy a kit... then another... and maybe, at some point, you'll present your own personal project. Or try other brands, other concepts, if you think that SU-V8 isn't what you want.
Good luck, best wishes,
Cosmin
Just a quick note: as you can see in my photo above, those Al clips are mounted on front of Q316 (and Q315), and not on the back as it should be for a better thermal transfer. The reason, probably, positioning issues.
Hi
So very close to spec for the old capacitors. Is that a good ESR? I am in rush to change the main capacitors, that is good the original emitter and diodes can handle more capacitance, as the original emitter and rectrifier diodes would be of good quality.
Thanks for the tips on the clips. I can see how its costly to change the transformers, however i think Technics would be of good quality and hard to replace, and at expense if they had to be replaced.
I love Dustinator and both SU-V8s They are my favourite amplifers i own.
We got well off topic. I have those transistors above i mentioned to try. How did you find the sound quaility with the Toshiba transistors Australian business Wagner claims to have the 2SA1124/2SC2632 in stock, however i am not sure if they are originals I will do a sheet up to compare the specifications. The transistors Wisholdtech mentioned are discontinued. Of the transistors i have i think the KSAKSC i would try.
Thanks for the luck best wishes
Sam
So very close to spec for the old capacitors. Is that a good ESR? I am in rush to change the main capacitors, that is good the original emitter and diodes can handle more capacitance, as the original emitter and rectrifier diodes would be of good quality.
Thanks for the tips on the clips. I can see how its costly to change the transformers, however i think Technics would be of good quality and hard to replace, and at expense if they had to be replaced.
I love Dustinator and both SU-V8s They are my favourite amplifers i own.
We got well off topic. I have those transistors above i mentioned to try. How did you find the sound quaility with the Toshiba transistors Australian business Wagner claims to have the 2SA1124/2SC2632 in stock, however i am not sure if they are originals I will do a sheet up to compare the specifications. The transistors Wisholdtech mentioned are discontinued. Of the transistors i have i think the KSAKSC i would try.
Thanks for the luck best wishes
Sam
Hello,
I consider every change I made in my SU-V8 having no impact on sound quality. Maybe a little cleaner sound, but not something 'in your face'. The only plus I consider is a prolonged life. By not using this amp currently, after around 2 years in my service, it means I'm using something else. Getting older, my hearing is worse... and I moved toward what's considered 'opened' sound and a sort of diy.
Best regards,
Cosmin
I consider every change I made in my SU-V8 having no impact on sound quality. Maybe a little cleaner sound, but not something 'in your face'. The only plus I consider is a prolonged life. By not using this amp currently, after around 2 years in my service, it means I'm using something else. Getting older, my hearing is worse... and I moved toward what's considered 'opened' sound and a sort of diy.
Best regards,
Cosmin
Thanks Cosmin, the replacement transistors the Toshibas didnt change things much in terms of sound,, so i may try those since they worked for you. I;ll research more the KSA/KSC in the meantime., as on paper they seem good. Best Regards Sam
@anatech
Hi Chris,
With the transistors i have on hand, would the KSA/KSC series be best? i know Cosmin has had success with the Toshibas he mentioned.
Also, i have 7 stranded silver plated wire, i have used in one Technics SU-V8 ? Does this look corroded the old wire ? Silvery tinny on the external but the copper appears dull underneath if I wrapped it. I have already solded some of the wire with the old wire, but isnt much troulbe to replace it, and I dont think the silver will make things bright,, , better for signal transfer and power I would expect
Thanks Sam
Hi Chris,
With the transistors i have on hand, would the KSA/KSC series be best? i know Cosmin has had success with the Toshibas he mentioned.
Also, i have 7 stranded silver plated wire, i have used in one Technics SU-V8 ? Does this look corroded the old wire ? Silvery tinny on the external but the copper appears dull underneath if I wrapped it. I have already solded some of the wire with the old wire, but isnt much troulbe to replace it, and I dont think the silver will make things bright,, , better for signal transfer and power I would expect
Thanks Sam
@lomis and any V8 owners
Hi Cosmin sorry to disturb you again so soon, if possible would your V8 have 2 fuses like the one here in the photo i found online? if so how is the wiring done, i have 2 orange wires labelled A and B, Grey Labelled A and B and Black Labelled A and B
Ive had a snag with the silver SU-V8, since i had trouble with one of my hardrives ive lost some images of the wires before i took it apart to clean up and restore the cabinet from rust etc.
See the 2 fuses attached to chassis near the power button. I lost my files with which wire went where. I labelled the wires A and B after the 2 fuses (this image above is all i could find,
As with the service manual
Is it correct the adjustment procedures
Thank you Cosmin and All
Have a nice Easter Break
Sam
Hi, Sam.
My amp is already back in its place, I'll open it again later and take a look.
I followed the adjustment procedures from the service manual.
So, the transistors 'issue' in the black one is solved? Since you moved to another chapter in the other amp... I'll friendly reiterate what I wrote before: if you do not like your amplifier in its original, functional form, then move on. Or try another set of speakers... or another sound source... I don't think is restauration what you're doing. Improvement? In my opinion, not necessary. But, of course, is a matter of personal choice which I totally respect.
Anyway, I'll be back here in a few hours with a post regarding those fuses.
Regards,
Cosmin.
My amp is already back in its place, I'll open it again later and take a look.
I followed the adjustment procedures from the service manual.
So, the transistors 'issue' in the black one is solved? Since you moved to another chapter in the other amp... I'll friendly reiterate what I wrote before: if you do not like your amplifier in its original, functional form, then move on. Or try another set of speakers... or another sound source... I don't think is restauration what you're doing. Improvement? In my opinion, not necessary. But, of course, is a matter of personal choice which I totally respect.
Anyway, I'll be back here in a few hours with a post regarding those fuses.
Regards,
Cosmin.
Hi Cosmin,
Thank you so much for looking, as i am really confused. The service manual is correct then i can proceed.
Yes, Dustinator the Black SU-V8, i took the transistors out of the silver SU-V8, as the black V8 had issues, which i traced to a transistor, I first thought it was the relay so i put a new one in, and it work pefectly, however the issue returned next time i used it. ,
Then i had to search for new transistors for the silver V8, and i have installed the KSC/KSA. I am not sure if need heatsinks for them, so i may get some.
I love the V8 amps, and the sound with my small mods.
As for mods, I usually only change the speaker terminals, better rca socket for the cd and phono, and new internal wiring. CD players upgrade the caps, usually opamp and rca socket.
The V8s love all my speakers even the Celestion SL-6 with copper domes,. It has very very low sensitivity at 82dB, however the V8s dont seem to mind, and sound great with them.
Thanks again,
Regards
Sam
Thank you so much for looking, as i am really confused. The service manual is correct then i can proceed.
Yes, Dustinator the Black SU-V8, i took the transistors out of the silver SU-V8, as the black V8 had issues, which i traced to a transistor, I first thought it was the relay so i put a new one in, and it work pefectly, however the issue returned next time i used it. ,
Then i had to search for new transistors for the silver V8, and i have installed the KSC/KSA. I am not sure if need heatsinks for them, so i may get some.
I love the V8 amps, and the sound with my small mods.
As for mods, I usually only change the speaker terminals, better rca socket for the cd and phono, and new internal wiring. CD players upgrade the caps, usually opamp and rca socket.
The V8s love all my speakers even the Celestion SL-6 with copper domes,. It has very very low sensitivity at 82dB, however the V8s dont seem to mind, and sound great with them.
Thanks again,
Regards
Sam
Hi,
One fuse connect the black wires together, the other one, the orange wires.
Please let me know if there's anything else I can help with, because I really want the amp back on its shelf (to access it, I have to remove other devices on top of it).
Good luck!
One fuse connect the black wires together, the other one, the orange wires.
Please let me know if there's anything else I can help with, because I really want the amp back on its shelf (to access it, I have to remove other devices on top of it).
Good luck!
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Hi Cosmin,
Thank you so much, i really appreciated it. I am so sorry you had to remove other devices to access your V8. I have 6 wires, orange, black and brown labelled A and B. I remember seeing on the Back Fuse, wha looked like it had 2 wires attached to each. That is what i needed, so you can put your V8 back. Did you V8 have the lights on the front for each connection? Ive seen some online but they dont seem common.
Thank you again
Regards
Sam
p.s
I hope to have some photos and videos of both the V8s back in action to share with you soon
Thank you so much, i really appreciated it. I am so sorry you had to remove other devices to access your V8. I have 6 wires, orange, black and brown labelled A and B. I remember seeing on the Back Fuse, wha looked like it had 2 wires attached to each. That is what i needed, so you can put your V8 back. Did you V8 have the lights on the front for each connection? Ive seen some online but they dont seem common.
Thank you again
Regards
Sam
p.s
I hope to have some photos and videos of both the V8s back in action to share with you soon