Peavey Classic 30 - Boosters

[raulgrell]

I just bought myself a Classic 30, should be getting here by Monday

When I tried it out, I found it didn't have enough drive to it. I usually play blues and jazz, but occasionally I delve into hard rock and some metal. I was aware, when I bought the amp, that it was not designed to make it to metal... But hey, If I ever want it to do metal, I'll just kick on a Dr Boogie or something. However, it would still be interesting to try get the tubes to make it to metal territory.

Therefore... A Booster!
I've searched the forum, and guys found nice results with the Minibooster and the Gus NPN boost, don't know if it got them metal though. I was wondering if any of you guys had  any boosters (or overdrives, I guess) that work well with the Peavey classic 30...

What kinda conflicts with my idea, is that I also wanted to get some more clean headroom. Yeah, it get's hard here... I was wondering whether I could sub the tubes for something a bit lower gain, which would give me the headroom... But I still need a booster that will make up for the drive loss...

I was also wondering about chucking a booster between the pre and power amp... Thoughts?

I was also looking for any interesting mods you guys may know, or any ideas I could try out (schematic, in case any of you are interested, just copy paste link into adress bar if it doesn't work: http://raulgrell.tripod.com/c30.gif - I only left the preamp and poweramp, for clarity)

Sorry for all the questions... I'll be sure to record some samples of the amps and the aforementioned boosters...

Thanks guys!

[comfortably_numb]

Pic not working.

[raulgrell]

just copy paste the link into your address bar... damned free hosting

[gutsofgold]

I wouldn't classify the minibooster as a booster even. It's quite a bit of color to your tone and has it's own distinct distortion (as opposed to a clean volume increase). I would search out a boost with a dedicated gain control.

[comfortably_numb]

As far as tube changes go, the 12AU7 will give you less gain and a softer, rounder break-up.  The 12AT7 has quite a bit more gain and will clip much harder.

[blues_mang]

I've been using a Classic 30 for a couple of years. My biggest suggestion is to first change the speaker. The Blue Marvel that comes stock with the amp doesn't do it any justice. I tried a few before settling on a Celestion Vintage 30. This gave it more edge for a hard rock sound, but still kept it clean and smooth for blues.
Check out the amp mods on this site: http://www.blueguitar.org/.  The article is old, but he gives some great ideas for mods to the amp and some great suggestions on tube replacement. I ended up going with a Chinese Golden Dragon for the tube driver for better clean headroom and JJ's for the rest of the preamps. It made the dirty channel a little more useable.
As for a boost pedal, I use Jack Orman's MOSFET boost. I like it because it's super clean and just gives a nice volume boost to push the amp just right.
Mine is an older amp, so I ended up getting a tube tamer to keep the power tubes from rattling and a tube guard to protect them when I'm transporting it. These were the 2 biggest faults with the design. Overall though, I absolutely love this amp. It loves every pedal I throw at it. I downsized from a 72' Twin Reverb because of the weight issue and only on occasion do I regret it.

[petemoore]

I was aware, when I bought the amp, that it was not designed to make it to metal...
  Funny...amps that aren't designed to make it to metal basically make great metal amps.
  {Dual Recto etc aside}.
  Gregs been using the C-30 ever since he got a Behringer modeling amp [and sold it...lol]. Classic 30's a great amp, if I we're after a metal tone, it would I think be a fine starting point...a pedal or two should be able to take it to hard metal / heavy rock...if that's shifting categories enough for ya...
  Speakers for certain make a difference, tubes somewhat also [I would use what is good in there, spares changed when needed], that amp'll *distort the output section N/P...IME what you want is exactly that, a strong 30w is about right for having *it and not ear bleeding.
 
 

[Renegadrian]

I hate peaveys - I tried a lot of them and never got a decent sound, both with bass or guitar...
Anyway, I'd say go for Rocket boost or Sparkle boost. That's the two I like the best...

[Steben]

Metal,.... 
I see a lot of 12AX7 in the schematic...
Not enough gain for you? 

[newfish]

Congrats on your C30 - I've had one for 10 years or so, and can honestly say I love it.

Any kind of 'dirty' boost makes for a great rock tone - and I normally only have the O/D channel's Gain set at 8.

I look at it this way...

Clean channel - clean.

Clean Channel with Boost - Gritty

O/D Channel - O/D.

O/D Channel with Boost - Really quite silly. 

Pretty much any kind of boost will work - even a Fuzz Face with the 'Fuzz' backed off.

[Steben]

even a Fuzz Face with the 'Fuzz' backed off.

You know you're classics! 
Tube amp with backed off Fuzz Face... as daily bread ...

By the way, raul:

What about power amp distortion?

[raulgrell]

Metal,.... 
I see a lot of 12AX7 in the schematic...
Not enough gain for you? 

True, there are plenty of 12AX7's in there... There should be plenty of gain, I was surprised myself when I first saw the schematic... I guess it's the way they're set up...

I've been using a Classic 30 for a couple of years. My biggest suggestion is to first change the speaker. The Blue Marvel that comes stock with the amp doesn't do it any justice. I tried a few before settling on a Celestion Vintage 30. This gave it more edge for a hard rock sound, but still kept it clean and smooth for blues.
Check out the amp mods on this site: http://www.blueguitar.org/.  The article is old, but he gives some great ideas for mods to the amp and some great suggestions on tube replacement. I ended up going with a Chinese Golden Dragon for the tube driver for better clean headroom and JJ's for the rest of the preamps. It made the dirty channel a little more useable.

I've seen his articles on modding the classic 30 - he's got some awesome stuff. I'm already prepared to change some of the tubes. I've heard alot about a 5157 or something along those lines, that seems good for V1 (clean tube). I'll probably go for either that one there or the aforementioned 12AU7... A nice thing about this amp is that I can mess with the clean part for added clean headroom, and the overdrive for more distortion separately... The thing with the speakers is they are pretty expensive...

What is generally wanted from the driver tubes?

I hate peaveys - I tried a lot of them and never got a decent sound, both with bass or guitar...
Anyway, I'd say go for Rocket boost or Sparkle boost. That's the two I like the best...

You know, I was thinking that exact thinking when I tried it... but DAMN the classic 30 really just... kicks ass...

Thanks for the input guys! I will be building a MOSFET boost, NPN boost, and a Sparkle Drive so far, maybe a Minibooster (some coloration might not be a bad thing)... Any more you think are worth it?

even a Fuzz Face with the 'Fuzz' backed off.

By the way, raul:

What about power amp distortion?

What about it? I was still wondering about the booster between the preamp and the power amp... any thoughts? It would be pretty sweet to boost the signal from the clean channel and getting the powertube distortion - I definately prefer it... I do know that the clean channel, when cranked, has a pretty sweet OD sound to it...

[newfish]

I'll see if I can get time to record some C30 clips this weekend (having just finished cooking up a batch of Si Treble Boosters).

Boosters are designed to give a little grit past 12 o'clock - and if anyone says the circuit is *slightly* similar to a Rangemaster, I may well blush...

SIngle tranny boost - BC108 (B I think...)

Anyway - sounds good either way - and with the boost at full, gives a lovely feedback / sustain thing.

[jayp5150]

I second a speaker change. I put a Sheffield in mine (which is basically a Vintage 30 rip-off).

Watch out for impedance, though. It sounds better with an 8ohm speaker, but this it that amps minimum handling, though, so you lose use of the speaker jack. Of course, if you ever wanted to use a different cabinet, you can just unplug the internal speaker, and you're good. What a lot of people do (and I think was mentioned in the blueguitar articles) is add a phono plug/jack in line with the internal speaker hook up so you can just unplug it and use that as your speaker out.

As far as a lot of 12AX7s in there... well, there's one for the clean channel alone, and 3 total; in comparison, the 5150 has 5.

I can get some decent blues rock sounds out of mine with no effects, but it responds really well to a Sparkle Boost. I had the Gus' NPN boost for a short time as well, and that seemed to work wonders also. I never did like the boost button, and I never use it, but thought about tearing into some of those mods to make it more useful.

The only quirk I have noticed is that the reverb becomes super sensitive with a booster in front. Then again, I'm fairly new to boosters--maybe that's normal. All you have to do is back it down a notch, anyhow.

Hope that helps. Enjoy the new amp. I love mine more the longer I have it.

[raulgrell]

What's the whole thing with impedance and amp health?

I thought tubes were more sensitive to loading differences than SS amps... Wouldn't it be bad to hook up the 8 ohm speaker to a 16 ohm tap? Or is it only when the speaker impedance is greater than the tap impedance?

[newfish]

AFAIK, the Speaker's impedance has to match the Output Transformer's impedance - to give the most efficiency (and therefore athe best possible sound).

Mis-matching the two can 'load' the OT - meaning it's being asked for more current than it has (am I right?) - which can damage things if this 'loading' gets too bad.

I've heard horror stories of people switching their valve amps on without any load attached (i.e. no Speaker Cab connetced) - with disasterous results (blown output tubes, blown OT etc).  The kind of thing you only do once, right?

A mate of mine has a Harley Benton 1 x 12 extension cab - with selectable impedance - which makes a lot of sense in my book.

[jayp5150]

What's the whole thing with impedance and amp health?

I thought tubes were more sensitive to loading differences than SS amps... Wouldn't it be bad to hook up the 8 ohm speaker to a 16 ohm tap? Or is it only when the speaker impedance is greater than the tap impedance?

All I really know is that you can use a cabinet with a higher impedance (4 ohm head with an 8 ohm cab=no issues), but you don't want to go below the minimum rating of the amp.

So, since the C30 is an 8ohm minimum load, if you change to an 8ohm speaker (which you should definitely try), you can't use the extension jack, as it is in parallel with the in-cab speaker.

It's set up with a 16ohm from the factory, that way you can plug in a 16ohm cab and have a total load of 8 ohms.

[petemoore]

  I used to say and think I hate peavies.
 Never owned one.
 They made litters of cheesedoggy amps, you could get into a solidly built amplifier in the 70's or 80's, and live life on either the cheesey, or the doggy settings.
 Lots of various types of cheese available...and 'cheep', yet well built.
 I feel there was a cost balance meeting in which red and blue chips were distributed a bit unevenly between some creative design engineers and marketing strategists...many interesting prototypes went into production early...and ever since, there's been a Peavette' amp in 1/2 of the garages or basements of locals, try the phase.
 The strategists were able to say 'here's the speaker, but we got a great deal on pots, which we find confusing in large numbers on one panel, so use as many of those as you like !
 Classic 30 is an amp I looked at, Greg uses on across from the drummer from me. First saw it after I knew a bit better about how to judge amps...basically on everything they are, in this case 239 got 30w of EL84 action and a cabinet and speaker...the wrong cabinet and speaker for allowing the amp to really take off but..
 heckuva deal, and there are ways to get medium grade transformers and do quite well, the rest of it is...just fine, low noise, the thing hums, and growls when pushed.
 Great little amp, depends on what you're doing, and what you have sitting next to it  .
 It's a Peavey tube amp, kikks the amp it replaced, which then went right out the cash window.
 I'd use it or recomend it until the other one is sitting right there next to it that does a host of tricks [which are all based around output tube distortion or stompboxes], and is somehow found as preferable to the C-30...I can't really see why very easy, at least not in the general sense...ie this guitar/that amp thing.

[newfish]

...am now intrigued.

My amp says "16ohm" on the extension socket.

I've always been wary of replacing the speaker - and will probably go for another 16ohm, but am now very tempted to try different speakers.

...and I have a friend who works for an EE company, and I *know* he can get good deals.

Any advice on the Jensen / Celestion / Unknown debate is more than welcome...

[petemoore]

but you don't want to go below the minimum rating of the amp.  
 No, you don't.
 Those ratings are written in such a way that causes confusion = amp failure in guitar players...just try to explain it to someone who had it explained wrong to them.
 Like the other guitar player, Greg, who had it explained backwards, and routinely asks me if I have "any more of them EL84's 'layin' around'?" cause my amps actin' up again...
 He says: "Pete...the guy's an engineer !" [some 'e' dude told him run it that way...lol]
 AUGHHHH...'*the guy's an engineer !' [I've developed a disdain for that set of words].
 ...then: "That's not it" [as response to my comment: "That's why your output tubes go bad all the time"].