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Calling All "Vintage" Integrated/Receiver Owners - Page 656

post #9826 of 13430
Quote:
Originally Posted by wotts View Post

Quote:
Originally Posted by DarKen23 View Post

cool.gif Thank you kindly LugBug1, Ive had that vsx-406 receiver for awhile now--when all else fails the 406 is always there, only if it had more transparency. I have another Onkyo receiver possibly older, I cant remember the year and model but Ill check when I get to work tomorrow *crossing finger* hopefully its a gem.

Yea that Sansui is sick. Id like to have one just to look at the purty colors.


That is exactly why I bought mine. I've used it a few times, but the lights are more fun.
Give it here tongue.gif
post #9827 of 13430
Quote:
Originally Posted by dryvadeum View Post



The power knob has come off and is a bit bent but it still works. I think it needs a clean though cos I tried using my LCDs with it and the channels were cutting out or had crackling whenever I fiddled with the volume or filters.

Any advice on cleaning it?

http://www.audiokarma.org/forums/showthread.php?t=207005

post #9828 of 13430
Quote:
Originally Posted by dryvadeum View Post

My father in law just gave me a Kenwood KA 9100. Are they any good?

Score!! They are nice amps indeed.

A word of advice though... For some unknown reason, Kenwood decided to use powerpack output modules on these amps, rather than discrete outputs. The powerpacks are now unobtanium, so if they blow, the amp becomes an paperweight.

I'd get the amp serviced at an absolute minimum, and if you are happy with the sound, consider getting a rebuild.

This gives you an idea what the amps are like internally, and what is involved with a recap and restoration:

http://www.cdkands.com/ka91002/ka91001.html
post #9829 of 13430
Quote:
Originally Posted by petemac110 View Post

Score!! They are nice amps indeed.

A word of advice though... For some unknown reason, Kenwood decided to use powerpack output modules on these amps, rather than discrete outputs. The powerpacks are now unobtanium, so if they blow, the amp becomes an paperweight.

I'd get the amp serviced at an absolute minimum, and if you are happy with the sound, consider getting a rebuild.

This gives you an idea what the amps are like internally, and what is involved with a recap and restoration:

http://www.cdkands.com/ka91002/ka91001.html

I read through that link and am speechless...........the time and effort put in is incredible. Wonder what the cost for that project was?
post #9830 of 13430
Quote:
Originally Posted by Oregonian View Post
 
Quote:
Originally Posted by petemac110 View Post

Score!! They are nice amps indeed.

A word of advice though... For some unknown reason, Kenwood decided to use powerpack output modules on these amps, rather than discrete outputs. The powerpacks are now unobtanium, so if they blow, the amp becomes an paperweight.

I'd get the amp serviced at an absolute minimum, and if you are happy with the sound, consider getting a rebuild.

This gives you an idea what the amps are like internally, and what is involved with a recap and restoration:

http://www.cdkands.com/ka91002/ka91001.html

I read through that link and am speechless...........the time and effort put in is incredible. Wonder what the cost for that project was?

When I saw "this is not routed right!" I knew I had seen that web page before...

... it's just like restoring an 1967 Mustang from an old rusted junker... either you enjoy doing that sort of thing or you don't... if you do enjoy it, then you have a fun hobby, and you have a great amp (or car) when you are done...

 

My restored Sansui AU-417 came from a guy whose hobby is looking for Sansuis and then restoring them in his free time.   His day job is car technician (coincidentally)...


Edited by kstuart - 9/15/13 at 5:24pm
post #9831 of 13430

Do we have anybody in here who knows the inner workings of these vintage Pioneers?

 

Pretty much every time I start my SX-750 up I get some distortion and channel imbalance for the first 3-5 minutes. It will go away after a few seconds and then sometimes come back after a few seconds or minutes. It'll go away on it's own or go away as I adjust the volume knob. I've already shot a whole bunch of DeOxit in all of the pots. To me it just doesn't seem like it's a pot issue since it goes away completely after about 5 minutes or so of warm-up. After about 3-5 minutes of warm up time it goes away completely and won't come back for the rest of the listening session. After it warms up it sounds spectacular, but it's just a bit annoying that it takes a few minutes to sound right. 

 

Is there something wrong that I can fix, or is it simply the unit warming up? 

post #9832 of 13430

Congrats to Oregonian and JasonB on being selected for the loan of the Alpha Dog !

post #9833 of 13430
Quote:
Originally Posted by jasonb View Post
 

Do we have anybody in here who knows the inner workings of these vintage Pioneers?

http://akdatabase.org/AKview/albums/userpics/10004/Pioneer%20SX750%20Service.pdf

post #9834 of 13430
Quote:
Originally Posted by Oregonian View Post


I read through that link and am speechless...........the time and effort put in is incredible. Wonder what the cost for that project was?

 

I'm not quite sure what the going rate would be over in the USA for this kind of work, but you'd be looking at around $500-600 for a commercial workshop here in Australia to undertake a thorough resto like that, or around $300-400 for a non-commercial vintage specialist/enthusiast to undertake the work. There's certainly plenty of demand for the latter category - it is my hobby and keeps me quite busy!

post #9835 of 13430
Quote:
Originally Posted by petemac110 View Post

I'm not quite sure what the going rate would be over in the USA for this kind of work, but you'd be looking at around $500-600 for a commercial workshop here in Australia to undertake a thorough resto like that, or around $300-400 for a non-commercial vintage specialist/enthusiast to undertake the work. There's certainly plenty of demand for the latter category - it is my hobby and keeps me quite busy!

That cost is very reasonable. Including parts?
post #9836 of 13430

thanks for that, but it doesn't tell me what my issue is, or if I even have an issue.
post #9837 of 13430
Quote:
Originally Posted by jasonb View Post
 
thanks for that, but it doesn't tell me what my issue is, or if I even have an issue.

The way you word the description is a little ambiguous.

 

However, a few days back, I mentioned that someone at AK pointed out that it takes up to 5 minutes for the Bias current to stabilize.

 

If there is never a problem after 5 minutes, then that seems a likely explanation, that it takes that long to stabilize.

post #9838 of 13430
Quote:
Originally Posted by jasonb View Post



thanks for that, but it doesn't tell me what my issue is, or if I even have an issue.

If playing with the volume pot can make the problem completely go away before the 3-5min warm up time, then the pot would seem to be the issue. But if you pretty consistently have to wait for warm-up to get normal operation, it sounds like a marginal component (maybe transistor?) that requires warm-up before it's stable. Some have used cold spray to try and isolate bad components, but I've never done that myself. Seems okay as long as it doesn't create moisture leading to possible shorts. Could even be two issues if the playing with the pot helps, but doesn't fully resolve the issue before the 3-5min is up.

Do you have a service manual? There are certain known marginal transistors that don't age well.
post #9839 of 13430
Quote:
Originally Posted by Oregonian View Post


That cost is very reasonable. Including parts?

 

 

Yes, that includes parts and labour, but generally excluding the large power supply caps. They can vary from $40-100 depending upon the amp (eg. four 15000uf 63V Nichicon Gold Tunes are $100).

post #9840 of 13430

Question for the more knowledgeable here. On many of these vintage receivers/amps, there are 2 phono inputs. Are those inputs on the same circuit from the beginning or do they merge later or not at all? Thanks.

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