Results 1 to 33 of 33

Thread: Non-electrolytic replacement caps, Orange Drops, etc - Your thoughts please?

  1. #1
    Old Timer olddawg's Avatar
    Join Date
    Dec 2007
    Location
    Carlsbad, CA and Kona, HI
    Posts
    1,526

    Non-electrolytic replacement caps, Orange Drops, etc - Your thoughts please?

    I have found myself recapping a few amplifiers lately. Many people recommend "Orange Drop Caps", Torres Engineering even has them with his name on them as "the best" orange drop caps . Fliptops recommends a different yellow axial cap that looks more like the old red Astrons. Recently when an old amp of mine suddenly quit I replaced the non-electrolytic caps with new 630 volt brown NTE brand Mylar/Film caps. They were available locally in 10 minutes and cost $1 each. They seem to work fine. There are botique UTV Ultratone replacement caps for $50 apiece. I figure any modern cap has got to be better than the 40 year old paper caps that were in the amp. Is there really any discernable advantage to using specific brands of film caps or is it all hype and attitude? I know people who sware that they can hear a difference with their botique speaker cables. Heavy guage copper lamp cord has always sounded the same to me. Is it like that?
    Last edited by olddawg; 12-09-2007 at 06:49 AM.

  2. #2
    Senior Member
    Join Date
    May 2006
    Location
    Cornelius, Oregon
    Posts
    1,155
    If you're looking for differences in sound, then you'll notice much more difference from changing speakers, tubes, and transformers, or modding the circuit to change voltages than you will from changing caps. That said, there are subtle differences from changing caps. The brand doesn't really matter though as long as any brand you are using is good quality. What matters more is the composition of the cap. Orange Drops come in film/foil polypropylene (715P and 716P) and film/foil polyester (6PS, 225P). Torres's "Orange Drops" are probably very similar to the others and I wouldn't bother honestly. Mallory 150's are metallized polyester. Sozo's are film/foil polyester, etc. Polyester caps tend to sound rounder and browner than polypropylene, with less highs. For a guitar amp, polyester are usually better to my ears, but for bass or hi-fi, polypropylene can sound better in certain places. The old paper caps tend to leak DC, and if they don't now will eventually, but they can sound really good too. Theres also paper-in-oil, military NOS sealed paper caps which will probably outlast all other paper types.

    Best advice would be to get various composition caps and try them out yourself and see what works for you.

    Greg

  3. #3
    Senior Member
    Join Date
    May 2006
    Posts
    1,209
    I think it depends on a bunch of things like what is being done? ("exact vintage restoration"? cost-effective repair? Experimentation?, etc.), Who is doing the listening (hypersensitive ultra-obsessive Eric Johnson-type ears guy/gal, casual hobby player, 70 year old with massive hearing damage, etc.), how much effort and money you want to spend obtaining a part(super rare vintage hard to find and expensive, super high tech and expensive, etc.), what sort of function in the circuit and effect on sound(coupling cap? snubber?, etc.).

  4. #4
    Old Timer olddawg's Avatar
    Join Date
    Dec 2007
    Location
    Carlsbad, CA and Kona, HI
    Posts
    1,526
    So in your opinion there will be a noticible positive tonal difference (closer to the original voicing of the amp) in using Orange Drops when compared to the mylar film caps I used in the coupling and phase inverter circuits? I used the NTE mylar film caps because they were convenient and I wanted to use the amp. It's not a big deal or expensive to order some and put them in. I just wonder if it is worth the trouble. I guess I'll find out. What is your opinion of mylar film caps for this application?

  5. #5
    Senior Member TD_Madden's Avatar
    Join Date
    May 2006
    Location
    Manassas, VA
    Posts
    695

    Topic variant.....Electrolytic replacements

    how about a variant of the question...

    Anybody using polyprop film as repacements for electrolytics? There's been a lot of progress in reducing their size in values large enough to handle power-supply filtering), but I can't find any evidence of folks using them for that purpose in guitar amps.

    R.G. Keen had a comment-stream running over at the Vox forum in PlexiPalace, and I'm interested in using them in my AC50 (replaced the original 32mf/450 caps with paralleled 20mf/600 since the B+ was about 511v...

  6. #6
    Better Tone thru Mathematics bob p's Avatar
    Join Date
    May 2006
    Posts
    2,580
    i think we'll have the definitive answer to the cap question as soon as @mykey finds this thread.

  7. #7
    Senior Member TD_Madden's Avatar
    Join Date
    May 2006
    Location
    Manassas, VA
    Posts
    695
    oh hell, that's JUST what we need!

  8. #8
    Senior Member
    Join Date
    May 2006
    Location
    Cornelius, Oregon
    Posts
    1,155
    So in your opinion there will be a noticible positive tonal difference (closer to the original voicing of the amp) in using Orange Drops when compared to the mylar film caps I used in the coupling and phase inverter circuits? I used the NTE mylar film caps because they were convenient and I wanted to use the amp. It's not a big deal or expensive to order some and put them in. I just wonder if it is worth the trouble. I guess I'll find out. What is your opinion of mylar film caps for this application?
    Mylar is a Dupont trade name for polyester. There will be a noticeable difference if you use polypropylene Sprague Orange Drops (715P and 716P) in place of the mylar/polyester ones you have in there, but it will be a subtle difference. Orange Drops, to my ears, tend to have a big bottom and somewhat harsh highs depending on the application. The mids in polyester caps usually sound more interesting to me too, but again, those are my ears. You might hear differently. If you use the polyester Orange Drops (6PS or 225P) in place of the mylars, there won't be much difference, though there will be some. Whether this will be a positive change or not depends on what you're going for? What kind of amp is it? What do you want to change about the tone as it is now? Changing caps are a subtle change to the tone....sort of like the creme on top of your hot choclate. It isn't necessary for the drink to taste good, but sometimes it can take it over the top and make it just right....and that is what the caps do, but you have to have your amp right before that with the circuit design, arrangment, voltages, etc.

    Greg

  9. #9
    Old Timer olddawg's Avatar
    Join Date
    Dec 2007
    Location
    Carlsbad, CA and Kona, HI
    Posts
    1,526

    Thumbs down

    Quote Originally Posted by soundmasterg View Post
    Mylar is a Dupont trade name for polyester. There will be a noticeable difference if you use polypropylene Sprague Orange Drops (715P and 716P) in place of the mylar/polyester ones you have in there, but it will be a subtle difference. Orange Drops, to my ears, tend to have a big bottom and somewhat harsh highs depending on the application. The mids in polyester caps usually sound more interesting to me too, but again, those are my ears. You might hear differently. If you use the polyester Orange Drops (6PS or 225P) in place of the mylars, there won't be much difference, though there will be some. Whether this will be a positive change or not depends on what you're going for? What kind of amp is it? What do you want to change about the tone as it is now? Changing caps are a subtle change to the tone....sort of like the creme on top of your hot choclate. It isn't necessary for the drink to taste good, but sometimes it can take it over the top and make it just right....and that is what the caps do, but you have to have your amp right before that with the circuit design, arrangment, voltages, etc.

    Greg
    The amp is the 1960 Ampeg Rocket I discussed in an earlier post. I replaced the filter can and found the tremolo was weak. In repairing the tremolo I discovered the phase inverter caps were leaking. Since I needed to use the amp soon, I used the NTE mylars that were immediately available. I am trying to get a concensus because I need to recap my 1963 Blonde Tremolux and a couple of other amps also. I have an AS degree in electronics and worked as a bench tech on solid state audio/video equipment for many years. For that application one usually uses OEM parts. My experience in repairing tube equipment is somewhat limited so I am trying to get up to speed on the various nuances and idiosycracies. In the past I let someone else service my guitar amps. Now I want to do it myself, save some money, and do it right.

  10. #10
    Senior Member
    Join Date
    May 2006
    Posts
    1,209
    as long you replace with something similar enough and as long as the value is not too far off I would not expect a particularly noticeable change. So if the original was polyester, then one might at the least try to find polyester caps. But things like this can be subjective and some techs might try to find an exact period correct replacement, or something they feel is close or they hear is close or thought to be the best replacement by users and techs, etc. Some (dishonest) techs seem to replace things that don't need replacing either from sheer ignorance or just to charge more money (not suggesting anyone here is but just examples of the variety). There seem to be all sorts of situations out there from what I gather, so I guess you have to make the best judgment for your particular situation.

  11. #11
    Old Timer olddawg's Avatar
    Join Date
    Dec 2007
    Location
    Carlsbad, CA and Kona, HI
    Posts
    1,526
    Quote Originally Posted by dai h. View Post
    as long you replace with something similar enough and as long as the value is not too far off I would not expect a particularly noticeable change. So if the original was polyester, then one might at the least try to find polyester caps. But things like this can be subjective and some techs might try to find an exact period correct replacement, or something they feel is close or they hear is close or thought to be the best replacement by users and techs, etc. Some (dishonest) techs seem to replace things that don't need replacing either from sheer ignorance or just to charge more money (not suggesting anyone here is but just examples of the variety). There seem to be all sorts of situations out there from what I gather, so I guess you have to make the best judgment for your particular situation.
    The caps I am concerned with are mostly paper caps. Nos caps are usually a bucket of worms, possibly being as bad or worse as the ones you are replacing IMO. I am not worried about achieving a pristine restoration on the Ampeg which is a beater amp. I will be more concerned with the Tremolux since it is in excellent cosmetic shape, has never been worked on, and has two original cabinets. So it is potentially quite valuable and how I recap it may effect that value. However, I do use the amp. It is not a collector piece. Any advice is appreciated.

  12. #12
    Senior Member
    Join Date
    May 2006
    Posts
    1,209
    like you say NOS can be problematic. Some do seem to be reliable and hold up for a long time, while others can be leaky, usually go leaky, or even shorted sometimes. I observe techs doing different things. One might sort through a bunch of old ones and try to find non-leaky ones (this could be cost-prohibitive where the old ones have gained value on the NOS market and have become too expensive to buy in bulk and sort through. One might also wonder how such caps would hold up over the long run). Another might not use old ones at all to eliminate any sort of risk. Somebody else, maybe they try to find something new that sounds the same or similar. You could try different things like for example for oil cap replacement, maybe you could use the hermetically sealed "Vitamin Q" type for replacement since those are oil and seem to be quite reliable. There is some info on the net here (archives) as well as other sites (not necessarily amp sites--could be radio/TV oriented) about specifics on the observed reliability of old caps. Regardless of what you do, if you do have a bad leaky cap you will need to change it for the amp to work correctly, so you'll have to do something... unless it's one of those Nigel Tufnel amps that you can't play or look at.

  13. #13
    Senior Member
    Join Date
    May 2006
    Location
    Cornelius, Oregon
    Posts
    1,155
    I'm not sure when Fender started in with using the blue Mallory "Molded" caps, but it should be right around when your Tremolux was made. The older Fenders were using Astrons a lot and almost all of those caps are leaky from what I have seen. On the other hand, the blue "molded" Mallorys are great caps and still usually work just fine. I wouldn't replace any of those unless one was non-functional or was leaking DC. For ceramics, I'd probably replace those with new good quality ceramics or silver micas, depending on what sound you're after. A lot of people who are looking for old Fenders have learned enough about the insides of the amps to really be looking for those old blue "molded" caps, so changing them out wouldn't be suggested unless they are bad. My 2 cents anyway.

    Greg

    P.S. Those old blue "molded" Mallorys were paper and polyester/mylar caps.

  14. #14
    Old Timer olddawg's Avatar
    Join Date
    Dec 2007
    Location
    Carlsbad, CA and Kona, HI
    Posts
    1,526
    Quote Originally Posted by soundmasterg View Post
    I'm not sure when Fender started in with using the blue Mallory "Molded" caps, but it should be right around when your Tremolux was made. The older Fenders were using Astrons a lot and almost all of those caps are leaky from what I have seen. On the other hand, the blue "molded" Mallorys are great caps and still usually work just fine. I wouldn't replace any of those unless one was non-functional or was leaking DC. For ceramics, I'd probably replace those with new good quality ceramics or silver micas, depending on what sound you're after. A lot of people who are looking for old Fenders have learned enough about the insides of the amps to really be looking for those old blue "molded" caps, so changing them out wouldn't be suggested unless they are bad. My 2 cents anyway.

    Greg

    P.S. Those old blue "molded" Mallorys were paper and polyester/mylar caps.
    Yeah, those were Astrons I was replacing in the Ampeg Rocket. Fliptops recomends these: http://www.fliptops.net/catalog/prod...roducts_id=284 There seem to be a few posters on this site who own they're own shops. Would any of you guys be willing to give a rule of thumb cap replacement guide such as, replace the Astron paper caps with this kind, replace the blue molded Mallorys with this kind? Even a chart guide would be nice. These years of Fender amps use this replacement, etc?

  15. #15
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    21,382
    Dammit, I typoed my whole response away.

    There is no wrong part to use. And who knows who made those caps for NTE anyway?

    Modern film caps will all work fine in this amp, and differences will be subtle tonal ones. It will make less difference than brand of guitar string. Can you listen to a recording and hear D'addarios from Fenders? When you get the golden ears, then worry about brand.

    REstoring the amp to original specs is a myth. Back then 20% tolerance parts were common. Leo Fender was not going to spend extra for 5% parts when 20% was good enough. That means your 100k plate resistor could be anything from 80k to 120k and be within spec. ecaps were spec'd at +80/-20% most of the time. Your coupling caps were no more precise. Today 5% parts are expected, and 2% parts are quite common too. Not so back when your amp was made.


    SO to try to "match" the original sound with some particular brand, is to me wasted effort. Two amps side by side off the line didn't sound the same. There is nothing to match. SOme guys have their favorites, and involved rationalizations for every choice. But not everyone prefers the same tone, so the guy who likes shrill amps will chose different parts from the guy who is after smooth sound.

  16. #16
    Old Timer olddawg's Avatar
    Join Date
    Dec 2007
    Location
    Carlsbad, CA and Kona, HI
    Posts
    1,526
    Quote Originally Posted by Enzo View Post
    Dammit, I typoed my whole response away.

    There is no wrong part to use. And who knows who made those caps for NTE anyway?

    Modern film caps will all work fine in this amp, and differences will be subtle tonal ones. It will make less difference than brand of guitar string. Can you listen to a recording and hear D'addarios from Fenders? When you get the golden ears, then worry about brand.

    REstoring the amp to original specs is a myth. Back then 20% tolerance parts were common. Leo Fender was not going to spend extra for 5% parts when 20% was good enough. That means your 100k plate resistor could be anything from 80k to 120k and be within spec. ecaps were spec'd at +80/-20% most of the time. Your coupling caps were no more precise. Today 5% parts are expected, and 2% parts are quite common too. Not so back when your amp was made.


    SO to try to "match" the original sound with some particular brand, is to me wasted effort. Two amps side by side off the line didn't sound the same. There is nothing to match. SOme guys have their favorites, and involved rationalizations for every choice. But not everyone prefers the same tone, so the guy who likes shrill amps will chose different parts from the guy who is after smooth sound.
    Thank you Enzo. Now that's what I wanted to hear and more in line to my original post. So most of this cap mojo is hype in your opinion? Like I said earlier, I understand tolerance and the fact that any modern cap will be superior to ancient failing technology. Personally I would prefer smooth over shrill. And you are right, the NTE sub could be any brand mylar film cap they contracted with. I would still be interested in hearing what serious restoration techs use as their favorites and their rationalizations.

  17. #17
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    21,382
    You'll have to read between the lines. What one man calls shrill, another calls bright and well defined. ANd what someone calls smooth or mellow, someone else calls dull.

  18. #18
    Senior Member
    Join Date
    May 2006
    Location
    Cornelius, Oregon
    Posts
    1,155
    I would still be interested in hearing what serious restoration techs use as their favorites and their rationalizations.
    From what I've seen cruising around the boards over the years, it seems that there are a lot of people using Mallory 150's to replicate the sound of the older paper caps. Some others use the Orange Drops, and still some others use Sozo, Xicon, etc. I used some Mallory 150's in a 1958 GA-20T Gibson amp and they sounded great. I used some of the generic yellow polyester caps that AES sells in a 1959 GA-20T Gibson amp and they sounded just about the same. I've used Orange Drops 715P, 716P, 225P, and 6PS in some Sunn and Silvertone rebuilds and they sound different, but also fine. I've used Solens in some Sunns too and they also sound fine but different. They all sound different from each other, but the differences are very minor and subtle, and some people don't even hear them. Its not something that you point to when hearing an amp on stage and say "yah, that one has Solen caps in it...I can tell by the way it sounds." If you're subbing parts in one after the other on a test bench and playing, then you might be able to hear some differences, but they are subtle. There's really no substitute to experimenting yourself and coming up with your own impression of what works for you.

    For old amps, aside from the electrolytics, I try to only replace what is necessary usually due to the cap leaking DC. The old yellow and red Astrons, bumblebees, black cats, and green Cornell Dublier's almost always leak too much DC and need to be replaced from what I've seen. I still check them for leakage though before replacing. The brown turd caps that Fender used in the first silverface stuff and Sunn used in some stuff don't usually leak, but don't sound very good and have a high ESR. I usually replace these as any new cap will be better than them. The later silverface used some blue caps and they usually are fine...I usually don't have to replace these. The blue "molded" Mallories almost never leak from what I've seen and sound fabulous so I almost never replace them. If I have to, then I use a Mallory 150 unless someone requests something else. Some unscrupulous techs will change all of the blue "molded" caps out, then turn around and sell them on ebay to the higest bidder. Thats not the way to be in my eyes.

    Greg

  19. #19
    Noodle of Reality Steve Conner's Avatar
    Join Date
    May 2006
    Location
    Glasgow, Scotland
    Posts
    7,246
    I believe that all the "sound of capacitor brands" thing is just pure hype. The brand shouldn't make any difference, as long as they are the same value and don't leak!

    Enzo, you make an interesting point, does this mean that after rebuilding an old amp with new components, or cloning an old design, we should expect to have to tune it to taste?

    On a similar note, I heard that transformer iron has improved a great deal over the years. Modern stuff has a higher permeability and saturation flux density, but a much squarer B-H loop. In other words, old iron saturated gently, but the new stuff really saturates hard when it eventually does. This could make all the difference between fattening bass and just making it fart out.

    So, how long before people like Mercury Magnetics can't actually get transformer iron of low enough quality to make accurate clones? (Of course the cynic in me would say that they never bothered in the first place...) Issues like this worry me a lot more than capacitors.
    "Enzo, I see that you replied parasitic oscillations. Is that a hypothesis? Or is that your amazing metal band I should check out?"

  20. #20
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    21,382
    If you wanted to clone a particular old Deluxe or something, you would indeed need to measure all the components to capture the nuance of the particular unit. On average, parts in an amp ought to come out more or less similar, but just luck of the draw will make some amps tend more towards higher val;ues and other amps trend towards lower values. Yes most amps will have both. Just because the schematic says it, doesn't mean that was hte value of your part. But that in part explains why amps of a given model sounded different, one from another. And we have no shortage of folks here on a daily basis fretting (pun intended) over the value of the cathode resistor here, and the plate load there.

    +80/-20% blew my mind the first time I saw that on a cap.

    Who was it - Mesa? Matchless? - that had their people take speakers and whack the magnets with mallets before installing the speakers? It was intended to give the speaker a old worn-in tone, the tone of a fading magnet.

  21. #21
    Senior Member
    Join Date
    Jun 2006
    Posts
    439
    If the differences in sound between similar amps is due to the variations in
    tolerance of their components then it should be possible to start with
    a good approximation built from precision components and then vary these
    in small steps to creep up on the best sound (to whoever is listening).

    For example, if you build an amp with a 1% cathode resistor you could then
    vary the value of that resistor slightly, without changing anything else, and
    see what the effect is on the sound. By doing this to every component in
    the amp it should be possible to come up with a more precise specification
    that could then be used to produce copies that would vary less amongst
    themselves.

    I imagine that there is an enormous number of variations possible considering
    all the interactions between components in an amp making it difficult to try
    them all.

    I read somewhere about old amps with "the" tone being disassembled and
    measured to enable cloning them. Did it work ?

    Paul P

  22. #22
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    21,382
    Such disassembly and measuring was exactly what I described in the post above.

    Rather than mess with 1% types and increment, if you really want to get the exact sweet values, just mount small trimer pots. Dial in the optimum sound then pull the trimmer out and measure it. THEN order 1% in those values. I actually did that for a customer on an old SIlvertone. Each attempt to tweak made something else less desirable, so I mounted a half dozen little trimmers so now the customer can second guess til his heart's content. Plate loads, tone slope, etc.

    I have another customer who comes by every now and then and pays me for a "lesson," to help him learn about amps. He is going through a basic Fender design and adjusting every single part in it for "best" sound. "Enzo, where can I buy 496 ohm resistors?" He is now extremely happy with his amp, although it has some really odd circuits. There is a bleeder across every filter cap for example. And other extraneous parts. They work, it is just not real parts-efficient.

  23. #23
    Old Timer
    Join Date
    May 2006
    Location
    NYC
    Posts
    1,519
    Way too much hype out there.One of my favorites is the "balanced" PI tube being better in a guitar amp.Might be useful in Hi-Fi applications,but if all the other components are +/- 10-20% that "balanced" tube aint balanced any more,is it?I like Enzo's "trimmer pot solution".That guy gotta be losing his mind,tweaking his brains out.

  24. #24
    imo
    imo is offline
    Member
    Join Date
    Jan 2008
    Posts
    60
    That said, balancing the caps and resistors around the PI tube in my Vibrolux made a pretty noticeable difference, not subtle at all. Louder and cleaner.
    It seems that a lot can be improved with a couple of hours and a few bucks in parts. I don't ascribe to, or have the money for, the high end parts market, but i have been pretty impressed at the cumulative effects of changing a few resistors and caps in an amp.
    Ian

  25. #25
    Old Timer
    Join Date
    Apr 2008
    Location
    Oceanside, NY
    Posts
    1,649
    When doing restorations, what is actually more important than component TYPE (within reason), is component VALUE. Caps drift DOWN in value. Resistors drift UP. What needs to be determined is: do you want the amp to sound as it did NEW, or aged? This is particularly important if you are dealing with clients. Recap a vintage amp with all new caps of the correct value, even if they are the same original type, and you will most likely have an amp that sounds different than it did before the cap job. Ditto for plate resistors, cathode resistors, etc. This counts for filter caps too. Hence, it helps to measure what you are replacing first to help "pre-age" the replacement components, THEN decide on type.

    It is for this reason that I stock replacement caps and resistors that are about 10% below and above standard values, respectively.

    Enzo,

    In all due respect, you are both nuts AND have the patience of a saint!
    John R. Frondelli
    dBm Pro Audio Services, New York, NY

    "Mediocre is the new 'Good' "

  26. #26
    Senior Member capnjuan's Avatar
    Join Date
    Apr 2007
    Posts
    120
    Quote Originally Posted by olddawg View Post
    ... Personally I would prefer smooth over shrill....I would still be interested in hearing what serious restoration techs use as their favorites and their rationalizations.
    Hi olddawg; agree with earlier comment re/ Orange Drops; made to extreme tolerances and rugged but to my ear a little bright up top and tubby on the bottom. Again, just my opinion but I like the Sprague 150s for interstage coupling; very smooth, uniform top to bottom, and moderately priced. CJ

  27. #27
    Senior Hollow State Tech Bruce / Mission Amps's Avatar
    Join Date
    May 2006
    Location
    Denver, Colorado
    Posts
    3,040
    Quote Originally Posted by capnjuan View Post
    Hi olddawg; agree with earlier comment re/ Orange Drops; made to extreme tolerances and rugged but to my ear a little bright up top and tubby on the bottom. Again, just my opinion but I like the Sprague 150s for interstage coupling; very smooth, uniform top to bottom, and moderately priced. CJ
    We will assume you meant, Mallory 150s...
    Bruce

    Mission Amps
    Denver, CO. 80022
    www.missionamps.com
    303-955-2412

  28. #28
    Senior Member capnjuan's Avatar
    Join Date
    Apr 2007
    Posts
    120
    Quote Originally Posted by Bruce / Mission Amps View Post
    We will assume you meant, Mallory 150s...
    Thank you Bruce; in fact I did. CJ

  29. #29
    Senior Member
    Join Date
    May 2006
    Location
    Cornelius, Oregon
    Posts
    1,155
    When doing restorations, what is actually more important than component TYPE (within reason), is component VALUE. Caps drift DOWN in value. Resistors drift UP. What needs to be determined is: do you want the amp to sound as it did NEW, or aged? This is particularly important if you are dealing with clients. Recap a vintage amp with all new caps of the correct value, even if they are the same original type, and you will most likely have an amp that sounds different than it did before the cap job. Ditto for plate resistors, cathode resistors, etc. This counts for filter caps too. Hence, it helps to measure what you are replacing first to help "pre-age" the replacement components, THEN decide on type.
    I agree with you to a certain extent, but keep in mind that if you are trying to measure a cap to find out what value it is now, a leaky cap with throw off the meter's reading. Also, if you measured an amp all out and replace parts accordingly being 10% one way or the other for example, it kind of confuses things later on when the amp needs work again. The person working on it will have to figure out what your intent was with the part substitutions, especially if things have drifted again.

    Greg

  30. #30
    Old Timer
    Join Date
    Apr 2008
    Location
    Oceanside, NY
    Posts
    1,649
    Quote Originally Posted by soundmasterg View Post
    I agree with you to a certain extent, but keep in mind that if you are trying to measure a cap to find out what value it is now, a leaky cap with throw off the meter's reading. Also, if you measured an amp all out and replace parts accordingly being 10% one way or the other for example, it kind of confuses things later on when the amp needs work again. The person working on it will have to figure out what your intent was with the part substitutions, especially if things have drifted again.

    Greg
    Yes, you are correct on both accounts, but a good cap tester can get pretty close. In addition, I NEVER do component value mods without getting an OK from the client first, and I ALWAYS supply an updated, marked-up schematic later.

    I offer this as an option. Most customers keep it original, but a few of those subsequently complained about sonic changes, which is WHY it is an option.
    John R. Frondelli
    dBm Pro Audio Services, New York, NY

    "Mediocre is the new 'Good' "

  31. #31
    Member
    Join Date
    Mar 2007
    Posts
    72

    OK, how about where the caps are made?

    I know this Thread is old but the cap discussions were very interesting. I am replacing a PC board in a Vibroverb RI with a 6G16 turret board with all new components for a friend of mine. The original PC board is full of IC Illinois (very small) epoxy and ceramic caps, a bunch of 1/4 watt resisters. I'm using 716 OD, Silver mica, Mallory electrolytic K bypass, atom Filter Caps and 1 watt resisters. I'm interested in hearing some opinions/comments on whether or not this will improve the tone...I'm assuming that the Sprague caps are made in the US
    Norm
    Last edited by Normybaby; 11-15-2008 at 07:02 PM.

  32. #32
    Senior Member Enzo's Avatar
    Join Date
    May 2006
    Location
    Lansing, Michigan, USA
    Posts
    21,382
    Why would you assume that? They may be, but don;t assume it. FInd out.

  33. #33
    Member
    Join Date
    Mar 2008
    Posts
    100

    Caps vs everything else

    I love these cap discussions!
    In SW Missouri, we used to call this "talking shotguns"

    Talking shotguns is when someone is talking a whole lot about how you can, or can't, do one thing or another unless you are using a certain shotgun and ammunition type...

    My personal experimentation has resulted in my beleiving that there is more in your left hand, than anything else. Put a worthless gun, with worthless ammo in the hands of a good shooter.....the result will be better than putting an expensive gun, with custom ammo, in the hands of an amateur

    A really well balanced amp, with almost any componets in it, placed in the right hands will sound increadible....the tool is what the tool is

    Caps are tiny stuff in the tonal quest...

    Although, I beleive in quality...so I mostly use M150s and Spragues...whenever I can help it....so maybe I'm "talking shotguns"

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Marshall JMP 50w volume drops shortly after standby engages power
    By Thorny in forum Maintenance, Troubleshooting & Repair
    Replies: 2
    Last Post: 11-19-2007, 09:31 AM
  2. Traynor YSR-1 mysterious electrolytic capacitor
    By mlannoo in forum Maintenance, Troubleshooting & Repair
    Replies: 5
    Last Post: 10-27-2007, 04:20 AM
  3. voltage rating for electrolytic caps?
    By mike_mccue in forum Maintenance, Troubleshooting & Repair
    Replies: 2
    Last Post: 09-05-2007, 04:42 AM
  4. When did Electrolytic Capacitors get so darn expensive???
    By Slobrain in forum Maintenance, Troubleshooting & Repair
    Replies: 17
    Last Post: 05-06-2007, 02:32 AM
  5. EH memory man/drops volume
    By Jay in forum Guitar Effects
    Replies: 1
    Last Post: 03-02-2007, 08:18 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •