| Author | Message | ||
| Martyn Hope (martyn391) Username: martyn391 Registered: 02-2014 |
I've just become the proud owner of an old 112 SixtyFive. Not 100% certain of age but looking at the pots I think it could be '76. ( serial number is BN04504 and chassis number is 2275-65 EX if anyone can be more specific dating it?) It has the 12AX7 PI and silver badges and is in incredible cosmetic condition for it's age! As its new to me I plan to get it properly serviced in order to get the best out of it ( I'm a non starter when it comes to this sort of thing!) My main concern is that after about 5 mins of playing the amp sounds like it's going to die ( volume drops and distorts for a couple of minutes) but then comes back and seems fine. However, I don't want to risk anything terminal- I've read a little about the PI problems on the earlier models. So I wondered if there's anything obvious I can do to sort this before I can get it serviced ( I'm impatient and the service guy is busy busy!) I don't really want to use it until this is sorted. Secondly, I don't think the speaker is original ( there's no make / model info on it. Simply 8 ohms written on with a sharpie! Does anyone have any recommendations for a great speaker upgrade? Thanks! | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
Well, speaker preferences are going to range from EVERYBODY from celestion to jbl to radio shack(just kidding about THAT one!). I am using webers in my MM but they are 10's. I do have webers in my guitar gigging amp cabs too. They are cv123's that are Cerwin Vega models and I love them. They are a LITTLE boutiquey(?) but they are reasonably priced if in the US. Fo my money, the Eminence line offers just about any tone you want in any form you want and they are available worldwide so I'd probably shop there unless you're in the US. Shipping gets a little hinky when out of the us. Kind of depends on the style you play, how loud and the power of the amp. A single 65 watt amp into a single speaker will require a higher powered speaker to protect it from being smoked just by the shear power dissipation in the coil. As to the in and out thing, fisrt thing I would look at is caps, input jack corrosion and dirty tube sockets. That amp is 40 years old so if it hasn't been re-capped, it should be. Caps are cheaper than transformers. Then clean the input jacks of any corrosion and clean the tubes sockets. In and out usually means electro-mechanical problem. The PI tube usually works or it doesn't but that socket can be dirty too. Also, if you spend good money on tubes, get as good a PI tube as you can afford. Bias a little on the cool side and enjoy. Mike. | ||
| Bill Moore (bill_moore) Username: bill_moore Registered: 03-2013 |
I don't mean to hijack the thread, but don't down play the, (old), Radio Shack speakers. I recapped an old Les Paul for my sister in law a while back, and fully intended to install the Weber signature 12 I have in it, but that old RS alnico sounds great! | ||
| Dave Gossett (davey) Username: davey Registered: 05-2006 |
Yeah, I have to admit that way back in the day I bought and used tubes in my 2/12/65 from the local Radio Shack here in town. If I remember right they came with a pretty good "life time" warranty. That was about the only place here in town where you could find them. And back then I just thought, "Tubes was tubes.." | ||
| Dave Gossett (davey) Username: davey Registered: 05-2006 |
Oops, Apologies for getting off topic. Old guy rambling.. | ||
| Martyn Hope (martyn391) Username: martyn391 Registered: 02-2014 |
I think my original post was never on topic! I realised I asked 3 unrelated questions in one shot! Anyway, the great news is the amp is perfect inside and outside! A dry joint was causing the humming. Microphonic EL34's have been replaced and it sounds as great! Even though I'm unsure what the speaker is it sounds pretty good to me, so it will stay for now. ( my technician said its most likely a celestion) | ||
| Lars Verholt (lmv) Username: lmv Registered: 11-2009 |
The original MM-Eminence A12G AlNiCo speakers do show up on eBay and other places from time to time - sometimes just as recone candidates. There's the A12G with the 18oz magnet which I believe is the original version for the Sixty-Five combo. It has the horseshoe magnet. There is also an A12G-HD with a 28oz magnet that was used in the 212RH cabinets and the HD-212 combo. I *think* this is the one with the square 'cigarette pack' magnet (others may chime in). I haven't tried it myself but I was thinking that in theory you could put the 28oz speaker in a 65 Watt combo without issues. The heavier (by 10oz, hehe) speaker compensates for its lower efficiency with the bigger magnet and is thus able to handle more power and possibly stay cleaner when running the amp hot. A reconed original MM speaker, to me, is a great choice if you can get the basket/magnet part for a good price. A more expensive option is to have the AlNiCo magnet recharged prior to reconing. This will restore the speaker to its original efficiency as AlNiCo magnets lose about 2% of their magnetism per year. Cheers, Lars |
Tue, 03/25/2014 - 09:55
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