| Author | Message | ||
| jamie danter |
Performed a cap job on my HD130-2275. Used Sprague capacitors. Replacing the caps in the cap can, on top of the chassis, C42,43,44,45, can be difficult due to the tight fit. Mark the positive terminals with a "Sharpie" to insure correct installation of the caps, prior to removal of the old caps. A solder sucker can help remove the solder from the terminations. Heating the joint and flowing a small amount of solder can help with old solder joints. I found removing the wires from their terminations, prevented accidental melting of the wire insulation with the iron, and made the job easier. The cap on the driver board is easily removed and replaced. Make note of the positive on the cap. Lifting the pre-amp board is easily accomplished, after carefully cutting the harness wire ties,near the power transformer. There are six screws, and are held to the PC board by fiber washers. Loosen them, and there is no need to remove them. There is a fiberboard insulator running the length of the chassis side of the PC board. Care should be taken removing the fiberboard because it is brittle, and I found a piece of adhesive holding the fiberboard to the PC board, in the vicinity of the Channel 1 tone controls. Mark the PC board caps with the "Sharpie", noting the positive connection. A small flashlight will assist you locating the cap solder joints on the underside of the board. Mark the joints with a "Sharpie" Use the solder sucker to remove the solder from the joint. Same procedure with the rectifier board, as the preamp board. With the exception of the board will be up on its end. Careful with soldering this board. Excess solder will flow "downhill". Be sure to blow out the chassis with an air compressor or a PC aerosol "Duster", i.e. compressed air in a can. I use a "current limiter", a series connected lightbulb with an outlet, when powering up an amp that has been serviced. See Gerald Weber's book, "Desktop Reference of Vintage Amps", pg 123. A handy substitute for a variac. The lamp will glow bright if you have a short in the amp. I also plug in a "Ground Fault" outlet, from the wall to the "current limiter", from the limiter to the amp. Just an extra safety precaution. | ||
| Marc Mulay |
fyi- I'm not a tech but I picked this info. up and thought perhaps I'd share it for investigation or possible expansion-upon BY a qualified tech. I was told that in addition to the usual capacitors that require replacing after a significant period of time, the following should looked at for replacement as well, and I'll quote; "some 20uf @ 25V coupling caps right after the op amp that drive the driver transistors as well as one other 20/25 cap in this circuit that should be replaced, -observing polarity". The guy making the comment was "chief tech" for a large repair operation in the NY Metro area some years ago. His specialty was MM amps and he was very familiar w/ the HD210 series. I picked the comment up in an eMail response he'd made to me. Make of it what you will guys! Marc | ||
| Steve Kennedy |
When I do a "cap job", I not only replace the high-voltage filter caps but also EVERY electrolytic capacitor in the chassis! Electrolytics will dry out over time and they all should be replaced after a couple of decades just to ensure "freshness"! | ||
| Mulay |
Steve- Any chance that you're still in S. CA? :-) | ||
| Steve Kennedy |
Sorry... I lived in San Bernardino for 3 years in the late '60s but since I have been up in the Portland, Oregon area. Steve | ||
| Lewis Langley |
I have a 210-65, from late 1979. I don't use it much. I'd be surprised if it has 50 - 75 hours of use. It looks like it just came out of the box I've changed tubes (matched) every 2 or 3 years. The amp sounds great. But my question is, even though the amp is relatively unused - given it's years, do I have to recap? | ||
| Michael Kaus |
Your amp doesn't HAVE to be re-capped. It's just a good preventive measure to keep one from shorting through and taking out a transformer that would be VERY expensive to replace. Mike Kaus. | ||
| Herb Jones |
If the 210-65's trany gets cooked, throw out the amp. It's an amp - not an alter to G-d.  } | ||
| Terry |
Why not fix it!!!!!!!!!! Then you can stii go to the alter  | ||
| Anonymous |
I've got a 210-65, and I want to change the caps. I want to start with the 2 big 450V filter caps, but are there any other caps that I should also consider replacing (I wish to do this a step at a time...)? How do I safely discharge the old filter caps prior to replacement? Should I run a ground to a wall outlet ground post? Do I need to solder the new cap leads down at the current solder point(s), or is it acceptable to cut out the old caps high up on the cap, wrap the new and old filter cap leads together then solder? I dont have a variac. What can I use instead for the initial power-up? How long should the initial power-up be? Should there be no tubes installed? Where can I buy the filter caps? Is the original "Mallory" brand available? If not, what's a quality brand nowadays? Forgive me if I seem a bit amateurish. With a little guidance (and a thick pair of rubber gloves), I think that I can undertake this task with a minimum of seizures(ha ha). Thanks. | ||
| Steve Kennedy |
While it is safer to discharge filter caps through a resistor, you can let the amp bleed them down the majority of the way by pulling the plug while the amp is still ON (not in standby) and waiting a few minutes. Then disconnect AC power and turn the amp's switches OFF. If you wish, you can use a multimeter to indicate the remaining voltage level in the caps. Then (with the power disconnected, of course), short across each filter cap with a wire or a gator-clip for a few moments. Then do it again to make sure that the built-up charge in the cap has been completely depleted. In order to obtain the best connections with the new caps, it is better to remove the old caps and install the new ones exactly like the originals. Half-hearted wiring "short-cuts" are easy to spot and don't inspire confidence. My advice: If you don't know how to solder properly or don't have the proper equipment, then let a professional do it. If you don't have access to a variac, you can at least make a safety device (which is normally used in conjunction with a variac) consisting of a 60-100 watt lightbulb in a socket wired in series with the Hot leg of an extension cord. When you power up the amp for the first time after a repair, power the amp using this extension cord. When the amp is first turned on, the lightbulb will glow brightly for a second or two (this shows in-rush current & also "softens" the turn-on surge), and after the initial charging of the filter caps the glow should diminish to whatever is normal for your amp as far as heater current. If the bulb glows brightly all the time you have a short or some other high-current draw problem. If you know your tubes are good, it is better to power the amp up with tubes in it. The light-bulb current-limiter is much more effective when used in conjunction with a variac, but if you absolutely have to work on an amp without a variac this is at least some insurance and indication of potential problems. Mallory, Sprague & CDE (Cornell-Dublier Electronics) are the U.S. cap manufacturers that immediately spring to mind. You should have no problem finding what you need on the web, but you could start here: Triode Electronics Antique Radio Supply Digikey Mouser Electronics Angela Instruments Above all, remember.... THIS STUFF CAN KILL YOU! Getting "bit" by 700Vdc can stop your heart if you contact the wrong points. Keep one hand in your pocket (don't continuously lean on the chassis) and do live-circuit probing with a wooden or plastic stick/probe (NOT a pencil or pen... parts of these conduct electricity). Steve (Message edited by admin on December 30, 2005) (Message edited by admin on December 30, 2005) | ||
| Anonymous |
Thanks for the technical info. Actually, I 'chickened out' of doing the caps myself. When I was setting bias, one hand brushed against the power switch terminals. Need I say more? My feeling now is: Anything that I can fix with money - isn't worth risking my life/health on. I brought the amp to Dennis Kager (@ Central Jersey Music), whom I think is much more qualified, and more careful, than me. Thanks, Ann Onymous. P.S. As my eyes, teeth, and fingernails now emit light (21 cm photons), I will be acting as "Sky Projector" at New York's Hayden Planetarium - Rose Center - while their Zeiss Projector is on vacation in the Key West. | ||
| Steve Kennedy |
Choosing to stay out of a tube amp is always a good decision! Dennis Kager has an awesome reputation, I am sure you are in good hands! Steve | ||
| DAVID ELLER |
I HAVE A 212 130 HD I WAS PLAYING A GIG NOT TOO HEAVY AND I HEARD A LOOSE CONNECTION SOUND A KRACKLE LIKE A JACK WAS NOT IN ALL THE WAY AND THAN NO SOUND AND THE TUBES WERE BRIGHT ORANGE OR RED AND GET HOT ALMOST IMMEDIATLY IF IT IS EVEN ON STANDBY NOW I HEAR JUST A FAINT SOUND COMING OUT AND A BAD HUM I HAD NEW TUBES IN IT ALSO . COULD ANYONE GIVE ME ANY IDEAS ON WHAT TO CHECK. | ||
| Michael Kaus |
Sounds like you either lost bias and cooked the tubes or they wer biased to hot anyway and cooked. The part about getting hot almost immediately worries mr though. THe only thing running on standby are the heaters, which shouldn't get hot, just glow and get red. That could be signs of a transformer taking a dump. I would have the biased checked first. Do you have a 12ax7 inverter tube or one of the solid state driver models? Mike. | ||
| Dwave Tone |
FWIW, I dropped my 212-65 (tube PI) and cooked one of the OP tubes :o( After much looking, I found a bad solder joint on the driver board. They can be *very* hard to spot, so use a bright light. My .02 dB -Dwave | ||
| Rob |
what should the aprox cost be to have a pro complete recap of hd130 be.....I dropped mine off and wont get a price for a couple weeks because they are backed up...just wondering what i'm looking at......also getting 4 new 6ca7s and the inverter tube | ||
| Steve Kennedy (admin) |
Price can depend on a lot of factors including how many caps are being replaced, and in your case, which tubes are being installed. A cap job can run anywhere from $75 to $125, the tubes and biasing could be from $100 to $250. Groove Tubes 6CA7 "US Made" tubes or NOS U.S. tubes are like $80-$100 a pair so you can see there can be quite a wide price range. Steve (Message edited by admin on March 06, 2005) | ||
| Rob |
I took my 210 130hd to the local tech.... new tubes in hand .....had him do a cap job......he replaced 4 .....installed new tubes and a phase inverter tube which I bought from him....when I went to see him he said $180. for what was done...but he said he had some bad news.....my transf was going south and he didnt know where to get one.....well I told him I did ...thanks to this board.....so he said if I got it he'd put it in.......also wanted to know where he could get them......well I guess i'll have to tell him.........the only thing that bugs me is I bought this amp from another amp tech for more $ than I should have ......especially since he probably knew it was going bad..... | ||
| michael kaus |
I'd be interested in knowing how he justified taking you for that and THEN telling you about the trans. And how it's "going south". Also, those amps have a lot more than 4 caps that need replacing. The electrolytics in the main circuit board, the driver board and the bias supply caps should be replaced too. Four filter caps should be about $30.00 tops so with a tube at retail of about $15.00, I would say that is a little high. Mike. | ||
| Rob |
the tech who is fixing it is not the one I bought it from.....I supplied the 4 power tubes.....they supplied the phase inverter........they I guess replaced the 4 big caps.......I beleive he is going to install the trans for this price also.....I would apreciate info you could give me about the other caps because I hate to spend all this cash to have one burn it up after I spend all this money...i'm going to get the trans from mojo | ||
| michael kaus |
There are a number of electrolytics in that amp. The most important being the filters and the bias cap but they all should be replaced. I've got a 130 downstairs now-I'll count the caps and thier locations and get back to you but he should see them right off-their big and silver unless they have already been changed. Mike. | ||
| Rob |
Mike,I got my new trans from mojo in 2 days..that was fast....sat I'm going to take it to my tech and ask him about the other caps in the amp....so any info you could give will help......I'm wondering if they just dont want to do them.....I cant figure them out because I made it clear I wanted all the electrolytic caps done.......Thanks for your help..... Rob | ||
| michael kaus |
There are a total of 10 electrolytic caps in your amp counting the 4 in the power filter section. Two on the main board, two on the bias supply board, and two on the driver board. For gawdds sakes, at least have him change the two 150mF@50 on the bias board. It should have them all changed while you are doing it. Mike. | ||
| edward solberg |
Mike, speaking of the 150mF @ 50 dcv caps (I count five on the 2275-65 chassis on my combo 210-65; an early grid bias type I bought new in 1975 and have blown through ever since...it far surpasses my twin, IMHO). have you any idea where I might order them? I'm doing a complete cap job on my music man and am having a bear of a time finding a place that stocks the sprague cap in that size. I've gone so far as check out the mfg (vishay-sprague) and even they only have them for their distributors on special request. any help you might provide would be greatly appreciated. ed | ||
| michael kaus |
I usually get my stuff through Mouser or Digikey. Don't remember if the last one got EXACT values or not but I think so. Just remember, the voltage values can increase as long as they will fit and the farad value can be slightly off as long as it is more. I'm pretty sure mouser had them. Also, Triode electronics is great to deal with-they are FAST! | ||
| edward solberg |
I had already ordered my sprague filter caps from triode electronics... it was the other value (150mF @ 50vdc) that was throwing me off the track. Thanks for the tip to digikey; an incredibly IMPRESSIVE catalogue (to say the least). I wish I had given the entire order to one retailer or the other (it is just more convenient to receive all of your parts at one time, no?). digikey would have gotten the entire order had I known of their bigger selection and larger inventory of stock.... (oh, well.) thanks again, e. | ||
| greg |
what changes (if any) in tone or volume can (or should) i expect by replacing the caps? MM HD150R...i use it for bass, primarily. thanks. | ||
| Impersonal Trainer |
If new caps needed - Change 'em: amp is louder, fuller more assertive, good for another 10 years. Approx $150 by a pro, Other parts extra. Don't change 'em: Sounds the same for a while, sound degrades, loss of bottom end, damage to amp. Cost: Whatever your next amp costs. (posted elsewhere in error) | ||
| greg |
thanks, much appreciated. | ||
| Anonymous |
poker casino poker 536 | ||
| MM130-210HD+115RP |
I?ve got one maybe stupid question. Some guys here says you can smoke the output tubes or the output transformator if the HV filter caps goes bad. Is this possible? By looking at the schematics it looks like a short circuit filter capacitor would make the fuse blow or completely silence the output stage. A lowering of the capacitance would make a loudable AC hum from the speakers, but a weaker anode voltage. The capacitors is for smoothering the DC current. I?m no expert in tube amplifiers, but I?m an educated electronics engineer, and been in the business for 30 years. Tell me if I?m wrong. | ||
| mike kaus |
Well, I'm no engineer, that's for sure but if the filter stage goes to ground, which can happen if the caps short though, the current increase on the power supply stage is more likely to take out the power supply transformer but it has been known to short out the final windings on the OT and send the 725 going to the wrong places. It has also been known to take out the tubes and screen resistors. Most of the time, from MY experience though with MM's, it's the power supply trans that goes if the fuse doesn't blow quick. Mike. | ||
| Chris Haines (chris) Username: chris Registered: 02-2008 |
Hello all, This is my first post to the board. I bought a 410 130HD new in 78 which has served me very well over the years. It does not have the phase spliter tube in the preamp. The amp and my 335 were unused for well over a decade while attention switched to raising a family. Until just recently I rarely used any effects boxes but now that I'm doing a some gigging again I bought a Boss BD2 and a compressor to add a some variety and allow an instant switch to a little overdrive. About a year ago I was getting an on and off severe overwelming howling noise. I found a repair guy who used to do a lot of Fender repair and he replaced the tubes and cleaned things up (never had it in a shop before this). It has sounded fine since. Having recently read the posts here suggesting capacitor replacement as preventive maintainance I called him today and asked him to have a look. His opinion was split between agreeing with the replacement advice and "Don't fix it if it ain't broke." I can't say I hear anything wrong but having no other Music Man to compare to and not remembering what it sounded like when it was young I don't know what I may or may not be missing. I'm sure there are new affordable smaller, lighter tube amps (bought a light weight hand truck which solves for most terrain except a lot of stairs) available today that would suit the small rooms I've been playing in but as you all know you get attached to things. I've held onto my guitar for 46 years and amp for 30 and they sound good together so for now that's where I'm at. Chris | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
Well, those things are a handfull. I DON'T agree with your "tech" because he obviously isn't the one who will have to possibly buy a transformer if a filter cap goes to ground. That being said, I suggest re-capping the amp and continuing to play it. yes, there are light alternatives. I myself have gone to a head and 2-12 cabinets because of my age and back. If nothing else, build a box for the chassis and splt up the speakers so that you can carry them separately. That old crap about if it ain't broke........ doesn't cut it with me. Sounds more like somebody who doesn't WANT to do it. I've never known ANY tech who turns down work unless he's just in over his head. It's too hard to make a living doing this stuff to turn anything down. MM transformers ARE expensive and hard to get. Take care of it before it breaks. Mike. | ||
| Chris Haines (chris) Username: chris Registered: 02-2008 |
Thanks Mike. I am going to take it in. I've seen a few posts referring to the caps that should be replaced. On one post you said just replace the long silver ones. Does that apply to my situation? Chris | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
Yes, in your amp, they will probably be silver. Make sure that the caps on the driver board and on the bias supply board are also changed. The bias supply board caps are as important as any. Also, if your "guy" is used to Fender amps, make sure he orients the bias supply caps properly. Seems to me the bias supply is backwards in ss driver amps. In other words, there is + positive voltage going to the bias supply so the caps are backwards compared to a fender amp. |
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