moray james Posted June 26, 2012 Author Share Posted June 26, 2012 You are very welcome. I am sorry if I did not give the answer that you may have been hoping for. I understand the sentimental connection some pieces of equipment can have, You either have to decide to move forward to better and to make a new connection or full speed ahead and make it new again. I hope that you are good either way. With some searching I am sure you will find the help you need.Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted June 26, 2012 Share Posted June 26, 2012 Your question is a good one, answering it is a little difficult. New caps will sound much better than old ones but you are correct they will sound different.There is no simple answer other than to say that with the old caps you are courting disaster as the amp will eventually fail. Problem is that there are very many different kinds of capacitors each for different applications and they all impact the sound in different ways. This is where years of experience and listening come into play. I can also tell you that resistors will also impact the sound. The good news there is that there is generally no reason to change resistors unless they are fried or on their way and it is not hard to maintain the same type of resistors. For example it would not be wise to switch from all carbon composite resistors to metal film as you would loose a lot of warmth, this is because of character of distortion the carbon resistor has compared to the metal film resistors.I have found that if you have a compotent modifier do the workthey will do a lot of circuit cleaning up things like grounding and when they are done you have a better sounding unit than when you started. You could contact John Hillig in the St Louis area (http://www.musicaldesign.com/) he is one of the best modifiers in the country. Jim Strickland (Acoustat) and David Hafler chose John to breath new life into the Hafler line years ago so if thoses names mean anything to you you can ask if he will work on you amp or if he won't if he could recommend someone. Ols receivers and integrated amps are generally a nightmare to refurbush so it may take some research on your behalf to find a competant technician. I am sorry that I could not be more helpful but this kind of project is a bit of a can of worms finding new pot to fit with the correct values (sometimes impossible) and all manner of other things to deal with. Most tech just will not go there but there are guys. If you search you will find someone who can get you to where you want to be. Best regards Moray James. Moray, I have to disagree with you on a few points. New capacitors and/or resistors will not necessarily sound better than the originals. With some caps running 20% above or below their specified value, changing to caps which do not maintain that variance can affect the sound in a negative way. Likewise for resistors which usually run on the high side of their specified value over time. So, if a given piece of equipment sounds phenomenal the way it is, doing a full replacement of the caps and out of spec resistors may not yield the desired result, in my experience. I have always made it clear to folks seeking this type of restoration that the final sonic result cannot be predicted, and that they are taking a bit of a gamble that it will result in an improvement in the sound to their ears. It doesn't much matter if I can demonstrate improvements on the 'scope in such instances. Enjoy! Maynard Quote Link to comment Share on other sites More sharing options...
NOSValves Posted June 27, 2012 Share Posted June 27, 2012 Moray, I have to disagree with you on a few points. New capacitors and/or resistors will not necessarily sound better than the originals. With some caps running 20% above or below their specified value, changing to caps which do not maintain that variance can affect the sound in a negative way. Likewise for resistors which usually run on the high side of their specified value over time. So, if a given piece of equipment sounds phenomenal the way it is, doing a full replacement of the caps and out of spec resistors may not yield the desired result, in my experience. I have always made it clear to folks seeking this type of restoration that the final sonic result cannot be predicted, and that they are taking a bit of a gamble that it will result in an improvement in the sound to their ears. It doesn't much matter if I can demonstrate improvements on the 'scope in such instances. Enjoy! Maynard It is official... you qualify as a "Local Tech" or would Audiophool be a better fit? Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted June 28, 2012 Share Posted June 28, 2012 It is official... you qualify as a "Local Tech" or would Audiophool be a better fit? Craig, your comment made me laugh so hard I almost lost my breakfast (which would have been a shame as it was quite delicious!) Apparently you are not aware of the definition of an audiophool as it is used in this part of the country. Let me present the real definition for the enlightenment of the readers of this forum who may consider many of your specious arguments to be the gospel of the audio world: http://www.urbandictionary.com/define.php?term=audiophool Seriously though, I can't imagine you have ever done any real circuit analysis work using the 'scope (do you even have one?) or other test equipment. If you had, you would be aware that my comments are quite valid as it would have shown you that a, say, 20% variation in the value of certain components can affect the sound. I won't go into a lecture about the different parts of the circuit which can be affected by even normal component tolerances (you and anyone else are welcome to email for as much discussion on this as desired.) So, as usual, we disagree. C'est la vie (why do I keep reverting to these lovely French expressions?) It's up to those who post questions to sort out good information from the invalid and to be cautious about accepting advice from those who fart higher than their rear end. Quote Link to comment Share on other sites More sharing options...
johnbutterwickjr Posted June 28, 2012 Share Posted June 28, 2012 My first post after reading the mail on here for many years. Question for Maynard. Are you the same guy who did the service work for Damsel TV and all of the audio servicing for Sal at Home Music Systems about 45 years ago? You once commented on Rockaway, so I wondered. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted June 30, 2012 Share Posted June 30, 2012 Do own a scope.... now that is a real moronic thought. Um last count I owned 6 of them... You my favorite Audiophool to disagree with have about zero true knowledge of what you post. Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted July 1, 2012 Share Posted July 1, 2012 Do own a scope.... now that is a real moronic thought. Um last count I owned 6 of them... You my favorite Audiophool to disagree with have about zero true knowledge of what you post. Craig, I hope you realize how much entertainment value we give our fellow forum members with our discussions (busting your chops is fun, and someone has to do it so it may as well be me!) And since I have only 2 'scopes, I guess that makes you the better man (but I bet mine are bigger!!!) As to knowledge, well, I don't need to brag about my credentials or involvement over the years in the electronics and audio field. My offer to you continues- any time you want to have serious discussions about the assertions we both make, feel free to email and I will answer as time permits. I will gladly support mine with references or any other material you would like to see and hope you can do the same. (With all of this, I'm actually starting to like you a little-- I must be getting weird!!!!!) Quote Link to comment Share on other sites More sharing options...
derrickdj1 Posted July 1, 2012 Share Posted July 1, 2012 Ever heard the words tolerance and sprotsmanship? Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted July 1, 2012 Share Posted July 1, 2012 Ever heard the words tolerance and sprotsmanship? Hey Derrick! I can't speak for Craig (believe me, he sure wouldn't want that), but for me good sportsmanship ends when a person insults anyone who has a different point of view, calls them juvenile names, and insists that only they are correct without providing any explanation. It's like the school teacher who makes an obvious mistake but refuses to acknowledge it to his students and sticks to the incorrect point of view (like the time my daughter's elementary school teacher insisted that penguin was spelled penquin and said that the dictionary was wrong when it was brought to her attention.) I have never insulted anyone (on here or anywhere else) with whom I differed, preferring to explain my reasons and leave it at that. Your comment is appreciated and will hopefully do some good. Regards-- Maynard Quote Link to comment Share on other sites More sharing options...
NOSValves Posted July 1, 2012 Share Posted July 1, 2012 Hey Derrick! I can't speak for Craig (believe me, he sure wouldn't want that), but for me good sportsmanship ends when a person insults anyone who has a different point of view, calls them juvenile names, and insists that only they are correct without providing any explanation. It's like the school teacher who makes an obvious mistake but refuses to acknowledge it to his students and sticks to the incorrect point of view (like the time my daughter's elementary school teacher insisted that penguin was spelled penquin and said that the dictionary was wrong when it was brought to her attention.) I have never insulted anyone (on here or anywhere else) with whom I differed, preferring to explain my reasons and leave it at that. Your comment is appreciated and will hopefully do some good. Regards-- Maynard Well the thing is I don't bother to explain myself to you because I have no reason to do so... I also do not need to spout off my credentials... My thousands of happy customer are all the testament required so I let them do the talking. Honestly I have no interest in going back and forth with you or do I have the time to waste. I have never started one of our exchanges. It is your petty off handed comments that get this going! I state my opinions garnished from my real world professional experience that has a very long successful track record. If you don't like them move on... We never had a problem until I stated I have no faith in most local unknown nameless technicians ... YOU TOOK that statement out of context... Sure many true professional technicians exist... It is the fly by night types that work out there home at night with no overhead or protection/recourse for the customer. Also the sellers on eBay selling gear as "gone over" by some mysterious un-named technician which almost always equates to some half witt patched it up so it will play music for a day, week or month so the seller can get a premuim price... You may have had good luck in the past with Local technicians but this business has drawn some real low life characters over the last 10 to 15 years as vintage tube audio has made a resurgence. The economy being so bad sure hasn't helped since so many people will resort to anything to make a buck. Every Tom, Dick or Harry with a $15 radio shack soldering iron and a $5 multi-meter is now a professional technician.... Tell me this comment was not bait to draw me out.... Moray, you have made my day!!! But, get ready for the comments about how incompetent local techs are! I have already covered that issue in great depth in previous threads, so I won't get back on the soapbox. Enjoy--- Maynard Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted July 1, 2012 Share Posted July 1, 2012 We never had a problem until I stated I have no faith in most local unknown nameless technicians ... YOU TOOK that statement out of context... Sure many true professional technicians exist... It is the fly by night types that work out there home at night with no overhead or protection/recourse for the customer. Also the sellers on eBay selling gear as "gone over" by some mysterious un-named technician which almost always equates to some half witt patched it up so it will play music for a day, week or month so the seller can get a premuim price... You may have had good luck in the past with Local technicians but this business has drawn some real low life characters over the last 10 to 15 years as vintage tube audio has made a resurgence. The economy being so bad sure hasn't helped since so many people will resort to anything to make a buck. Every Tom, Dick or Harry with a $15 radio shack soldering iron and a $5 multi-meter is now a professional technician.... Now we have accomplished something! You have clarified the basis of your assertion (without any rude or insulting remarks), and I completely agree with you about there being some bad apples out there as well as many true professional technicians. Thank you! Now I'm going to go out and buy a lottery ticket...... Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted July 2, 2012 Share Posted July 2, 2012 My first post after reading the mail on here for many years. Question for Maynard. Are you the same guy who did the service work for Damsel TV and all of the audio servicing for Sal at Home Music Systems about 45 years ago? You once commented on Rockaway, so I wondered. Hi John! Yes, it's me. Sorry to be so long in replying but somehow I overlooked your post. Why have you waited so long to say hello on here? It has only been 40 years! Will PM with my phone # so we can catch up. If you still get up as early as me, around 5:30 is a good time to chat. Catch you later--- Maynard Quote Link to comment Share on other sites More sharing options...
djk Posted July 2, 2012 Share Posted July 2, 2012 " With some caps running 20% above or below their specified value, changing to caps which do not maintain that variance can affect the sound in a negative way. " This sounds like you know what you're talking about (to someone that doesn't really know), but how correct is it? Marantz (and most other designs) have the values for the coupling caps selected for -3dB points generally well below 1hz. Please explain how altering it from 0.72hz to either 0.90hz or 0.58hz (±20%) affects the sound in a negative way (example used a 1µFinterstage coupling cap driving a 220K load). Quote Link to comment Share on other sites More sharing options...
derrickdj1 Posted July 2, 2012 Share Posted July 2, 2012 When replacing caps in vintage amps, it is best to try and find the exact one from the manufacture, or the SQ can be affected. This can be difficult, but with a little effort they can be found in most cases. It should also be pointed out that some old amps have that unique sound because of the age of the caps, and even replacing the cap with one of the original ones, there may be a change in the SQ. The SQ of many of the vintage amps is as good or better than some of the current amps out there. The local repair shop may not be the best place to have a vintage amp restored, find someone that deal with restoration of that particular brand for the best results. The bias need to be reset, curcuit board checked, cleaned, old glue removed and other things for complete restoration. This can get a little pricy, but if it is a good amp, well worth the effort if you are into vintage equipment. Legendary amps dose that for the Yamaha amps from the late 70's and 80's. I plan on completing the restoration on my old amps which include a new exterior paint job and lettering. Quote Link to comment Share on other sites More sharing options...
tube fanatic Posted July 3, 2012 Share Posted July 3, 2012 " With some caps running 20% above or below their specified value, changing to caps which do not maintain that variance can affect the sound in a negative way. " This sounds like you know what you're talking about (to someone that doesn't really know), but how correct is it? Marantz (and most other designs) have the values for the coupling caps selected for -3dB points generally well below 1hz. Please explain how altering it from 0.72hz to either 0.90hz or 0.58hz (±20%) affects the sound in a negative way (example used a 1µFinterstage coupling cap driving a 220K load). I'm about to leave for a week or two at the beach. Send me an email and let me know if you have a copy of Radiotron, a function generator, 'scope, and a tube amp in which you are able/willing to swap out capacitors and resistors. When I get back, we can pick this up. Also, as a corollary discussion of this issue, read Rod Elliot's thoughts on capacitors here: http://sound.westhost.com/articles/capacitors.htm Maynard Quote Link to comment Share on other sites More sharing options...
erik2A3 Posted July 3, 2012 Share Posted July 3, 2012 I truly am baffled by the constant interstage coupling capacitor debate. I have to admit that I agree with the position that new capacitors of whatever type -- PIO, teflon, poly, mylar....or going way out on a limb....even electrolytic or ceramic -- are not a sure way of obtaining one's preferred play-back presentation. In fact, using a very spendy cap with vanishingly low ESR values, even though brand new and of the correct value, might offset a carefully established frequency balance in terms of the original design. One's own hearing acuity comes into play in terms of tolerance of specified values. There are so many times I remember where, for me, the better sound was obtained by using the vastly cheaper brand or type....and there were as many times that the higher cost species was clearly superior. My thought is that it, as mentioned above, can be extremely subjective at best, and very largely circuit dependent. Absolutely do enjoy the search, experimentation, and process! Erik Quote Link to comment Share on other sites More sharing options...
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