Quick, cheap, easy way to improve your valve or hybrid amp

Sure, a lot of bass amps are all solid state - with good reason. But, if you have all-valve (like me) or hybrid amps (a valve or two in the preamp section; eg Ashdown, Marshall DBS, etc) then consider this...

Nice as it is, a lot of 12AX7/ECC83 equipped amps come with some pretty naff pre-tubes as supplied. I don't rate the Russian or Chinese 12AX7s at all; certainly not for bass. They can be quick to distort (don't mind that) but are 2-D and brittle when they do so. I like Mullards, but Mullard, Telefunken and Amperex Bugle Boy get whacking bids on the Fleeb and even sillier prices from the vintage tube sellers.

A good, used, General Electric or RCA is often up for not a lot of money. I tried out (long, boring story) various 12AX7s blind and the Groove Tubes 12AX7 from China was obviously rubbish. The GE and RCA were actually better than the pricey, nicey Mullard. My guitarist sounded best through the Mullard so I re-checked. Yep, the bass sounded better through the GE.

Upshot; consider picking up an old GE or RCA 12AX7A or 7025 for just a few quid/bucks and be surprised when they go in. No great tech knowledge or skill is required but remember that all-valve amps can be dangerous, even when unplugged. Post here if unsure about what to do.

Equally, if you have other faves, post your ops here.

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Mexican church bell... clang :lol:

It occured to me that the Marshall B150 combo also has the same preamp features as the DBS stacks. It isn't cheap at around £500 but it's a big step up from the Peavey TKO/TNT stuff. Again, having that preamp valve removed and replaced with something decent will make a big difference.

Do you think its still worth looking at combos then? Bearing in mind I was only using the TNT150 for rehearsing. I'm lucky really, I never needed a rig to gig on as the guy I played for about 2-3k (power that is not £s) worth of PA that we lugged around for me, vocals and sometimes the acoustic. In bigger venues I went through the Pod into the backline.
I'm not gigging at the mo but intend to start again(eventually!) but now I will have to provide my own umpf. A stack always seemed more flexible.

This is all pie in the sky at the minute as rent is slightly more of an issue :roll: I really need to look at second hand stuff but I have no idea what to look for and even if you go view an amp can you really say "I'm just going to crank it up to 10 and see if it's ok for gigging" or 11 on the 'Spinal Tap' signature series!

Thanks for all your advice, I've been playing quite a while but know absolutely nothing about equipment, dutifully slapping hand now. Ow.

I have the traditional (read, old) bass player's aversion to combos for anything other than home strumming. A full rehearsal upwards would have me reaching for the separates. I suppose I'd consider a big combo if it were to be left at the rehearsal venue but, even then, might as well have the head and cab. What you want/need to get back into gigging bassist mode depends a lot on what you're going to play and where. Plus the financials, of course.

Rather than me blather on, you could have a look for The Bottom Line forum, and maybe subscribe to its digest email. I've recently unsubscribed because of the time constraints of eBay hunting, Plexi Palace (owners of smelly amps and valve-sniffers like me) and this place ( :) ). About 2-3 years ago they had a couple of threads like "Riggage for Giggage" and "Big Gig Little Gig", and I followed up with a thread on valve amps for bass. It's worth hunting down because TBL has posts from amateur students to well known (well paid) pros and makers and shakers in both guitar and amp making. Mostly American, but still you get the idea.

There is often an unhealthy obsession amongst bass players for 600+W heads. Why the need to have an amp nearly twice as loud as the guitarist's 100W amp is beyond me. Looking at guitarist's posts, they all seem to want attenuators or yank half of their valves out so they can get that "all the way to 11" tone without suffering nosebleeds. There is some strange truth that a 100W valve amp does appear louder than a 100W SS amp, but even so I've been fine with one 100W head in most situations (I don't do stadium gigs :cry: )

OTOH, only the young and the small-penised are absolutely insisting on that "2x18 and 8x10 cabs" thing. Anybody who lugs their own gear makes do with a lot less magnets these days. I saw a nice looking, Silverface era, Fender 2x15" bass cab on FleebUK and no-one wanted to touch it. Even with bass players for a living, it's quite common for a normal gig to be head + 2x10" or 4x10" single cab. The extra 4x10" or 1x15" is only lugged along for the bigger ones.

The advantage of SS power amps is how neatly this works. The head would be, say, 300W into a single cab @ 8ohms but connect the other cab in parallel and bingo!, approx 600W into 4 ohms for the bigger gig. With valve power, you just change the impedance selector from 8 to 4 and the same old 100W is now just moving a bit more air around.

For the kind of stuff you like, I think it'd be worth at least finding out what a bass through valves sounds like. The Ashdown Evo hybrid is well worth a tryout and, if you can't afford it, keep an eye out for the 200W and 400W DBS in case a cheapy comes up. I don't particularly like Hard-Fi but I do like the sound of Kai's bass. You should be able to hear/see a Realplayer clip of "Hard to Beat" or "Cash Machine" and listen for the bass. That nice growl is a Hiwatt valve bass stack.

Forgive me for committing necrothreadia here, but I was just wasting time reading through old posts and came across this thread.

Here's my oh-so-salient point: Radio Shack at one time carried thousands of tubes (valves to those of you who are separated from the U.S. by more than an imaginary line or a thousand miles of water). Had your old table radio go dead? Open it up, see which tube wasn't lighting up. Turn it off, let it cool, and pull out the tube. Go down to Radio Shack, check the shelves, do a cross reference, find the right tube, take it home, install it, listen to KIMN Radio, Denver 95, and hear about that new group, the Beatles, and how they're going to appear at Red Rocks tonight, if they can stay out of jail for the damage they did to the Brown Palace Hotel.

Some years back, Radio Shack went out of the tube business. Rather than send everything back to the warehouse, the stores sold off their stock. In some cases, a local repairman would come in, give them $100, and take away a couple thousand tubes.

Just makes you sick, doesn't it?

:) Threads never die, you just have to scroll down more. You're right, once the TV and audio market went solid state (and the military, but that's another story), plants in the US and Europe closed down and shops offloaded their stock. The guitar amp market alone isn't enough to sustain it. All that's left are the former Warsaw Pact countries and China.

I know one or two very astute people who bought entire 100-box trays of the RCAs, GEs and Mullards, Telefunkens and GEC especially and have been really coining it. Now they've mostly gone [a not-special pair of Mullard EL34s recently fetched £170 (over $300) on Fleeb], even the second rank stuff is going up.

TBF, modern production from China etc is getting better; making the job of salvaging old radios (as another chum of mine does) less necessary.

1bass is absolutely right on the mark with the tube info. If your amp is all tube and older or had a lot of use it is always a wise idea to have your tone caps checked, and if needed replaced. DO NOT ATTEMPT THIS YOURSELF !! These things can be dangerous even after taken out of your amp !!!!

Yes and, just to avoid confusion (I nearly said "crossed wires" but that's the kind of crap pun I try to avoid :oops: ), Pegleg doesn't mean the little capacitor on the tone pot - that's harmless. He's referring to what I call the filter or smoothing capacitor, often called "can cap" because it's the big, can-shaped, thing. Their job is to store up the AC humps and frrt it out as smooth DC.

It's the word "store" that's important. They store a whallop for quite some time even after the mains plug has been pulled out of the socket. Especially important for bass players because our valve amps are usually 450V, >100W jobs. An errant touch of those can be fatal. Best left to a tech or (in my case) someone who takes any excuse to wear full-length rubber.

Incidentally, I get very bored of vintage-amp-types who think that original filter caps are somehow better. There is nothing great about 30+ year old, dried out electrolytics. If there is any sign of powder puff around them, they must be replaced toot dasweet. When one explodes inside, it's a right burger to clean up.

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