soliciting for a headshell, powdercoat, and tweak

[theinteriorleag]

Hi guys,

I've no business being here b/c my tech skills are nil, but a gearpager suggested I ask you guys this...

I've just purchased a carvin x100b, and I love the clean sound. I want to get a new headshell for it, powdercoat/screen the chassis, and get the amp tweaked (its got some scratchy pots, but I'd like to give it a good checkup, see if there is anything to increase the headroom, and tweak the gain channel a bit to not sound so 80s).

Anyone interested or have a recommendation for someone to do this?
Thanks, jason

[Phil_S]

By "headshell", do you mean the metal chassis? If so, the amount of work involved in cutting a chassis, powdercoating it, and then applying some mods to a PCB (I'm assuming the Carvin is PCB) it likely to run more than it's worth.

If by "headshell" you mean the cabinet, that might be different. If the cabinet covering (tolex) is beat, it can be replaced if the cabinet is otherwise good. Remove the guts of the amp and take it to a furniture upholstery place if you can't find a better choice. If you need a cabinet and your chassis is standard size, then you can probably buy one. But again, a new cab isn't going to be cheap.

I'm a great believer in function over form. If you can't find an amp tech in or near where you live, see if there is a TV repair guy nearby. (This is a dying breed.) He should be able to take care of some of the basics like scratchy pots and may even advise on your other concerns.

[theinteriorleag]

Sorry...headshell meant cabinet. I figured it would be best to try to get someone to make me a cabinet (I don't think I'm going to find a local person), and find someone local to do the tech work on the electronics. I'm not sure who take the chassis and powdercoat it. I was just hoping maybe there would be a good one-stop shop for all this.

I know I'd end up putting a lot more into the amp than its worth, but it is likely an amp I'll stick with, so I'm ok with that. thank you.

[Structo]

Have you tried cleaning the scratchy pots?
Are you very handy?

If so, get some Craigs De Oxit and spray some in the gap by the wiring lugs. Then rotate the pot a few times.
I also like to spray some air (from a can) in there afterwards to help clean out the gunk.
If the pots don't clean up well, if you have any soldering skills, they really aren't that difficult to replace.

BE AWARE OF LETHAL VOLTAGES INSIDE THE AMP!

Map out the wiring and take pictures before desoldering.
Replace the pot with the same value and taper.

As far as powder coating and silkscreening the chassis goes....
That is going to be very expensive for a one off job.

I guess the best thing you could do is post some pictures for everyone to see to make knowledgable suggestions.

Often time different or new power tubes can change the headroom.
Also the bias current can change this too, earlier breakup- later breakup.
Different preamp tubes in the OD channel can also change the tone there as well.

Sounds like you need a good guitar amp tech.


I think in reality by the time you paid for the things you listed you could buy an amp that better suits your needs.

[Phil_S]

By way of example....
http://www.mojomusicalsupply.com/customcabinets.asp
Rather costly.

There must be a cabinet maker in your town. Go see him and show him what you need. He can whip it up out of scrap. I'll bet someone will make you a deal.

If you've never applied tolex, this is something that requires some knowhow. A custom made cab isn't the place to learn how.

Start looking for that TV repairman.

[muchxs]

I know I'd end up putting a lot more into the amp than its worth, but it is likely an amp I'll stick with, so I'm ok with that.

I'd take a whack at it but you're not kidding when it comes to spending more than the amp is worth.

The powdercoating bit is what really puts me off. To powdercoat the chassis requires that it be entirely stripped, that means tearing the amp apart and entirely gutting the chassis. I've done exactly that with automotive restorations, it's also what makes a bonafide restoration expensive.

The rest of it is no big deal.

Seriously, you'd be better served by locating an example of your Carvin in pristine condition and doing a few tweaks on that.

If you've never applied tolex, this is something that requires some knowhow. A custom made cab isn't the place to learn how.

Really? The tolex would be the least of my worries. Heck, by now I can probably apply tolex to your mother-in-law! Not that I'd want to!

Start looking for that TV repairman.

Last guy I'd call. The average TV repairman is so far removed from tube technology you wouldn't even know the gear originated on the same planet. My buddy Harry learned electronics years ago in the Navy, these days he pays the bills working on flat screen TVs. No tubes. Plenty of finicky little chips. Every so often we'll put our heads together and solve problems in an amp we couldn't sort out individually. Like I said, lucky he learned electronics years ago in the Navy.

[theinteriorleag]

I'd probably be fine with the front and back powdercoated, instead of the whole chassis. I'll keep looking for locals, but I also know I want something done well, and I don't know of anyone advertising these services. I know it will cost more than the amp is worth, hell I paid $220 for it, but the amp's clean is what I want to use. A tweak to the dirty would be nice to make it more versatile. That done, I want this amp to look different and am ready to pay for it.

[muchxs]

I'd probably be fine with the front and back powdercoated, instead of the whole chassis.

Do you understand how powdercoat works? It's a dry electrostatic coating. Parts to be coated have to be stripped down to the metal chassis then sandblasted to expose clean metal for the powder to adhere to. The part is connected to an electrode and the powdercoat gun is charged, the charged powder particles travel to the part and adhere. There's no solvent like normal paint. Next step is to bake the part in an oven, that's what converts the powder to a durable skin similar to stove enamel. It won't withstand temperatures like vitreous enamel but is otherwise somewhat similar.

Electronics won't survive the oven.

Yes I can get it done. Yes I'd have to outsource the powdercoating. Yes it would cost some bucks. Yes there are alternatives.

Post a pic of the amp.

[Tubetwang]

here my advice...

If you're goal is to gain knowledge/experience and money is no object...go for it.

If you want to do a nice job for the lowest greens...i'd buy a coated chassis from one of the vendors and rebuild the amp in it.

[muchxs]

here my advice...

If you're goal is to gain knowledge/experience and money is no object...go for it.

If you want to do a nice job for the lowest greens...i'd buy a coated chassis from one of the vendors and rebuild the amp in it.

Really? Then tell me where I can get a coated and silkscreened replacement chassis for a vintage Carvin X100. Maybe Carvin still has one on the shelf somewhere but it's a long shot, it's almost a 30 y.o. amp.

[Tubetwang]

Ok...you want exact?

Sorry, i got it wrong...

[gearhead]

here my advice...

If you're goal is to gain knowledge/experience and money is no object...go for it.

If you want to do a nice job for the lowest greens...i'd buy a coated chassis from one of the vendors and rebuild the amp in it.

Really? Then tell me where I can get a coated and silkscreened replacement chassis for a vintage Carvin X100. Maybe Carvin still has one on the shelf somewhere but it's a long shot, it's almost a 30 y.o. amp.

Seriously? Keep looking for one on ebay that has a chassis that looks good to you. It'd be cheaper than trying to buy a new-built chassis to drop your guts into. Also, you can always email Carvin, but chances are slim.

[muchxs]

here my advice...

If you're goal is to gain knowledge/experience and money is no object...go for it.

If you want to do a nice job for the lowest greens...i'd buy a coated chassis from one of the vendors and rebuild the amp in it.

Really? Then tell me where I can get a coated and silkscreened replacement chassis for a vintage Carvin X100. Maybe Carvin still has one on the shelf somewhere but it's a long shot, it's almost a 30 y.o. amp.

Seriously? Keep looking for one on ebay that has a chassis that looks good to you. It'd be cheaper than trying to buy a new-built chassis to drop your guts into. Also, you can always email Carvin, but chances are slim.

Sure. I looked. These come in two versions, there's a Boogie MkII type package and a more Marshall (y) looking package. But: It's not my amp and it may be the old "trying to make a cat do dog tricks" story. Arkansas Guy says he loves the cleans but the distortion doesn't satisfy. So what we're going to do is rip the entire amp apart, clean up the cosmetics then pray that it's possible to mod the distortion tone into something acceptable. So far no discussion of what an acceptable distortion tone sounds like. While I'd like to take the guy's money I also insist on returning good value for every dollar spent, I'm not so sure I could return good value here.

Here's the thing: If money is no object then the solution may be no further away than a brand spankin' new Carvin Legacy. Honestly I don't like the distortion tone on the Legacy but that may be because I've heard too many Trainwrecks and Dumbles. It has a big fat clean tone similar to a good '60s Fender tone IMHO. If I was going to fix the distortion tone I'd just use a cranked 'Wreck on one side of a Radial Switchbone with the Carvin on the other.

The Carvin is a circuit board amp so radical mods will require a radical amount of work.

http://cgi.ebay.com/Carvin-Electric-Gui ... dZViewItem

That's the amp we're talking about, right? If not I suggest you hike right over there and BUY IT! It looks pristine to me.

[Tubetwang]

a steal at 175$ if you ask me...

[John_P_WI]

Jason,

I've got the exact head cab shown on the ebay link that I bought new in '82 or so. A buddy of mine bought one in the early 90's that had EL34's and the distortion channel on his was a little meatier. Which version do you have?

I'll caution you that it will be a real pain to work on / mod. As mentioned before, everything is pc board based. I cut a few traces leading to the power tubes and jumped the cut with 1 ohm resistors to help set the bias, or use the bias meters available today.

I have not played it for 15 years or so, as I just don't need a 100 watt head... What I do remember is the clean channel is very clean, almost too clean / sterile for me and the distortion channel was very buzzy. I'm sure some adjustments of the Rplate, Rcathode + bypass caps, coupling caps and the addition of snubbers could help the distortion channel. The bass also was a little loose, didn't have the smack that the JCM 800s of the day had.

Probably the biggest bang for the buck would be to mod / change the MV to help the distortion quality. Depending how loud you play, a PPIMV may help with the distortion, although it probably would be difficult to incorporate and would affect the clean channel headroom too.

IMHO, try a few tweaks first, and if you can get the tones that you want / like then spend the money fixing up the chassis / head cab. I know back in the early 90's Torres offered a mod kit, they may still offer something if you contact them.

Funny thing about this post, I was just thinking about tweaking my X100b amp this winter, I'll let you know if I get around to it.

Peace,

John