matchless dc-30 users - your HELP needed!!!

[deek]

so I've been playing with a 2001 matchless dc-30 for about a year now and have finally decided to change the tubes on it. i ordered a brand new set of tubes - everything (cept the ef86 cos i had a nice one in already) and turned it on. i found that my headroom on both channels was really low - about 9 o'clock on the volume and i'm already buzz when i hit it hard with humbuckers (les pauls with burst buckers). maybe this is something i'm noticing for the first time but i thought it was a bit higher. so i swapped it out and put in my old tube set and it did the same thing - started to buzz at 9 on the volumes and really fuzzy at noon. i play this amp a lot of times at church so sometimes it's been a while before i get this krank this amp up a bit. but for some reason i thought it was a bit cleaner before breaking up so early (or what i perceive as it being early). anyway, if someone could let me know if this is typically and that i've gone crazy that'd be great. or if something has started to drift as well... or any other comments?

Thanks!!!

[jay42]

hmm...first ignore the position of the volume knob. How loud is it before distorting? 30W is loud enough that you can't really yell over it.

[gregc]

Do you have the master volume engaged? If so, disengage it. Should be pretty loud before distorting, especially the non-click channel. Try using the low gain input also, especially with humbuckers.

[deek]

yeah, should've specified... nope, no master volume on. anyway, it's loud at that volume at 9 o'clock but i think i can talk over it...

[Jono]

Mine is the same year... you shouldn't be hitting breakup until 11 o'clock, right?

If its a buzz... and you've swapped, old tubes, and back again... then its got to be something else. Check your power source - I found I got a serious buzz at one gig once when I used it on an isolated power supply.

Not too sure about the headroom. Which channel are you using? It could well be the EF86...

Best to take it to a decent tech and express your concerns. My guy has all of the equipment to measure the output and whatnot, and can tell me straight away if I'm at 100% or not. Hopefully your guy is good too...

[jay42]

it's loud at that volume at 9 o'clock but i think i can talk over it...That's not right. If your speakers are connected properly, I also think it's time to take it in. hth

[deek]

thanks everyone! sounds like i should take this guy in for a check up. oh, and by buzz i mean crunch i guess - or the overdrive sound. do you find the overdrive sounds a bit on the "flappy" side - if that makes any sense. i'm going to be trying it with my tele as well to see if it's just my humbuckers that are ultra hot.

[Kiwi]

One last thing ... check it's not on the 1/2 power setting.

=K=

[deek]

K - yup, roger that - power switch is on high. thanks!

[tlpruitt]

What brand of tubes did you replace the old ones with? What brand of tubes were the old ones?

The DC30 can sound very distorted with output tubes (el84's) that can't handle the DC30's voltages and cathode resistor value. Many online tube dealers offer el84 tubes that are rated/tested to work in the DC30.

As mentioned above, try putting the old tubes back in and see if the sound improves. If it does then the new tubes are the problem.

-Tim

[deek]

The only brands that I've used are JJ's (both new and old). I did swap back in the old tubes and it was still doing the same thing. Maybe something with my amp? Thought I'd never have to service boutique amps ;-)

[reubencox]

Man if you've been playing that amp for a year I would imagine you need new power tubes anyway. Those amps are biased so hot they eat up power tubes. But they sound soooooo good so I put up with it!

Anyway, the amp I own has a very similar 1st channel to the DC30 (guy who built it worked for matchless) and no master volume control. If I really really bang my tele it gets some crunch around 9 or 10. But you couldn't talk over it, it's pretty loud at that setting. On mine above 12 is pretty much impossible to get a clean sound out of.

[deek]

okay, i think my amp is functioning within normal parameters and my burstbucker pups are freaking hot. i just swapped out more tubes and plugged in my tele with avri 62 pups and i got more head room - i was almost at 11:30 on channel 1 for break up and around 10:30 - 11 on channel 2 (ef86) for break up. and with the paul these levels are obvious lower (as mentioned above). i spoke with a friend of mine who has an older dc-30 and stated that this was the same for him when using hot pups. so i think my mind was playing tricks on me and that everything is a-okay. i guess i was use to my old twin having to pump it to almost being dimed before there'd be a drive sound.

any comments on similar performance through their dc-30. i mean it sounds great i just thought (obviously deluted) that there was more headroom before i turned the volume knob a quarter of the way. looks like it was just the variance in my pup levels...