"I Wanna Hold Your Hand"

[jerryjg]

I recently bought a British class A amp ( Carlsbro) thinking I could get the Classic beatles tone from it like the song "I wanna Hold Your Hand" for instance. Now I dont know how much of that tone has to do with the guitars used? If someone could tell me what amp reissue to buy to get the same tone from that Beatles song/album. Is it the Vox Ac-30 reiisue that will give me that tone? Is the AC15 a lower powered version of the Ac-30? thank you.

[Kap'n]

"Class A" has virtually nothing to do with the way an amp sounds.

Virtually the only amps you can buy that are true class A are practice amps with a single power tube, like a Champ a Univalve, or a Valve Jr.

The AC30's the Beatles used were not "Class A," but hot biased Class AB. Again, not that it matters.

Guitars make a difference, amps make a difference, speakers make a difference.

What makes the biggest difference is how you play the thing.

[Rickenjangle]

George played a Gretsch Duo-Jet with flatwounds, and a Ricky 12 with flatwounds. John played the Ricky 325, probably also with flats. Plus, you've got to take into account the micing techniques, and the limiting they put on to keep the 'desk' from overloading. It's much more complex than just what guitar and amp.

Having said that, if you had a Gretsch or Ric with a Vox amp (I have the AC15, myself, and a Ric 360) you can sound quite a bit like the Beatles if you EQ the amp right.

[jerryjg]

"Class A" has virtually nothing to do with the way an amp sounds.

Virtually the only amps you can buy that are true class A are practice amps with a single power tube, like a Champ a Univalve, or a Valve Jr.

The AC30's the Beatles used were not "Class A," but hot biased Class AB. Again, not that it matters.

Guitars make a difference, amps make a difference, speakers make a difference.

What makes the biggest difference is how you play the thing.

Well, you say that "Class A has virtually nothing to do with the way an amp sounds". Yet here is a sentence the factory spiel from laney-"The range of VC30 combos offer classic British class A tone in a variety of speaker options."I have heard this from others as well- Carlsbro , I think included. This would allude to the fact that there is a certain identifiable "British class A tone".So...

[Kap'n]

Well, you say that "Class A has virtually nothing to do with the way an amp sounds". Yet here is a sentence the factory spiel from laney-"The range of VC30 combos offer classic British class A tone in a variety of speaker options."I have heard this from others as well- Carlsbro , I think included. This would allude to the fact that there is a certain identifiable "British class A tone".So...

No. It alludes that the marketing department at Laney has been working overtime to make you feel that a "British Class A sound" exists, you need that sound at all costs, and that your compelling need for one can only be satisfied by buying one of their products.


Essentially they're trying to tell you that it sounds like an old Vox. Does it? I have no idea. Given my experience with amps that claim to sound like a Vox, probably not.

[JAM]

One of the persistent myths, AFAIK none of the AC30 knock-offs are true class A. Like Kap'n says, it's just marketing.

[Kap'n]

AFAIK none of the AC30 knock-offs are true class A.

Which is a good thing. The AC30 isn't Class A either.

The only amps I am certain are class A are single ended ones:

Champ/VibroChamp
Univalve
Valve Jr.
etc.

Allegedly some of the Allessandro designs are Class A. I haven't verified that.

Anybody who tells you they have an amp with "a sweet, luscious, creamy Class A power tube overdrive" is blowing smoke up your ass. Even Mesa. Especially Mesa.

By definition, any power section that is being overdriven ISN'T class A anymore.

Randall Aiken on Class A.

...and for you who "know all about Class A" because you've read Mesa's Randall Smith's "White Paper" on Class A: It's riddled with half-truths.

[jerryjg]

Yes, I think it was you Kap, Sir, who said that the AC-30 is a hot biased AB amp. I dabble as a non-tech in the audio world. I have heard that it was possible to have up to 25 watts in pure class A. In this scenario, I think the Class A was always pushed to Class A_B at about 12 watts. From what I have ever seen, only the vintage Valve audio amplifiers like the "Leak TL-12" are true pure class A. I have heard of the old "Acrosound 20-20" brewing 20 watts class A, and the Altec 340-a , running at about also 25 watts being pure class A. No, I think beyond 12 watts, then things must begin to be AB, unless the Transformers are massive enough to stay Class A up to the 20-25 watt range.Even then you must be looking at some gigantic power transformers?Is there such a thing as 25-30 watts true Class A?? Is 12 watts the Limit?

[JAM]

Is there such a thing as 25-30 watts true Class A?? Is 12 watts the Limit?

I think it would depend on the output tube. For example a lot of audiophiles like the sound of a single ended Western Electric 300B, IIRC these put out around 7W. A very expensive tube - about $900.00/pair.

[Kap'n]

Sure, you could go over 12W.

Three 6550's in parallel, single-ended could do around 60 Watts Class A. Three 807's could do around 35W.

But why? If you're an audiophool, you might get off on it, showing off your silver wire transformers for your other audiophool phriends, but this is guitars we're talking about.

[pc]

But why? If you're an audiophool, you might get off on it, showing off your silver wire transformers for your other audiophool phriends, but this is guitars we're talking about.

[Fripperton]

Keep in mind a lot of what you hear has to do with where the mic was during the recording too. A few inches in location can totally change the sound.

[jerryjg]

I think it would depend on the output tube. For example a lot of audiophiles like the sound of a single ended Western Electric 300B, IIRC these put out around 7W. A very expensive tube - about $900.00/pair.

Last Audiophool post, but now that they are making reissue 300B's(Slovenia or Russia I believe), I wonder what the possibilites of using this tube in a Guitar amp application? I hereby claim any and all patents persuant to the excercise of this idea by way publication on this post.

[Wilko]

Ok. Back to the beatles guitar sounds in that period.
If you listen to the primary sound of the guitars, it's pretty easy to hear guitars with very short sustain being played fairly hard. The inital attack is fat as hell, then it drops off quickly into a very compressed sort of "jangle" sound. I think it would be damn near impossible to get with a Les Paul or Strat. A semi hollow Gibson might get you there, but I think you'd ned a fully hollow guitar like a 125, 330 or such. Forget Gibson humbuckers, you;ll need a much "twangier" bright sounding pickup. A p90 turned down might get you there. Flat wounds are not neccesary but will certainly help. Try a dan electro. You'll get real close to that old sound.
For amps, get a clean sounding old amp. Lose the reverb and turn up the treble and mids. FOrget "distortion" it wil lonly muddy up the sound and make it too "rock and roll" "garage band" sounding. Turn the amp up and the guitar down.
Trust the guitar and play it like an acoustic.

[Kap'n]

The last time I looked (early 90's) somebody had geared up to build "Western Electric" logo 300B's in the US. No idea if they're still doing it or not.

[JAM]

Last Audiophool post, but now that they are making reissue 300B's(Slovenia or Russia I believe), I wonder what the possibilites of using this tube in a Guitar amp application? I hereby claim any and all patents persuant to the excercise of this idea by way publication on this post.

Your real name wouldn't happen to be Randall Smith would it?

[Rickenjangle]

A semi hollow Gibson might get you there, but I think you'd ned a fully hollow guitar like a 125, 330 or such. Forget Gibson humbuckers, you;ll need a much "twangier" bright sounding pickup. A p90 turned down might get you there. Flat wounds are not neccesary but will certainly help.

You're hearing Gretsch and Rickenbacker pickups, mainly, as I said earlier in the thread. Wilko is correct in that the fat Gibson HB sound isn't going to help you get that sound very well, and is also correct that Fender single coils will not get you there. It's gotta be fatter than Fender yet twangier than Gibson. Semi-hollow WILL help, though it's not imperative.

[Kap'n]

You're hearing Gretsch and Rickenbacker pickups, mainly, as I said earlier in the thread. Wilko is correct in that the fat Gibson HB sound isn't going to help you get that sound very well,

Coils wired in parallel (like Filtertrons) rather than series (standard Gibson wiring) would probably get you closer.

[Durockrolly]

This is from Justins HRD site.

What is Class A?
Without getting too technical, all you really need to know about Class A is that it's a method of amplification that's been blown out of proportion—mostly due to marketing hype. Whenever an amplifier is referred to by a class of amplification it is always assumed that we're talking about the power amp, because all preamps are Class A. (Now it is certainly possible to set your preamp up as Class AB, but it would be so cumbersome no one has bothered to do so, nor will anyone ever bother.)

I think the reason Class A has become so hyped is because laymen tend to think Class A is synonymous with "Grade A." In other words, they believe Class A is somehow better because of the letter "A." This is an incorrect assumption. The reason Class AB was developed was to make up for the inefficencies of Class A power amplifiers. The reason for the letter "A" was because it's the first method of amplification that was developed, and therefore is also the simplest. This is why many old "student level" amps were Class A, because they are simple and therefore less expensive.

The vast majority of guitar amplifiers that claim to be Class A are actually something called "cathode biased," which really has nothing to do with the class of operation. This has led to the invention of a new non-technical phrase, "true Class A."

What is true Class A?
The exact same thing as Class A. "True Class A" is a catch phrase that was invented by boutique builders who wanted to let buyers know that their amp actually was Class A like it claimed. However, like the phrase "Class A" it has also been subjected to abuse and hype. Here is an example..

"Good features but the tube thing is really lame and ultimately just a marketing gimmick by Korg. Only true Class A tube circuitry is worth raving about and that would have cost Korg another 1000 dollars to include that- any other forms are just marketing gimmicks. Just like all the tube circuitry in effects pedals and cheap 200 dollar tube preamps- they are not Class A either."

Anonymous review of the Korg Triton Extreme synthesize on harmony central

While I agree there is a certain level of hype when a tube is used in a synth and called "Extreme", the reviewer has absolutely no idea what he's talking about as far as Class A is concerned. The synth uses a 12AU7 preamp tube which, because of the nature of preamplification, is undoubtfully cathode biased Class A—or what the reviewer calls "true" Class A. The same goes for pedals with preamp tubes—all cathode biased Class A.

Remember, the only time Class AB is ever used is for power amps because of its greater power efficency. Preamplification is used to shape your tone—it is not used to create large amounts of power! The synthesizer (and aforementioned pedals) do not have power tubes to drive a speaker—which would also require an output transformer. The reviewer also fails to realize that Class A is far less expensive than Class AB to implement as preamplification—the $1000 extra claim is just ludicrous. I included this quote because it was a perfect example of the many who regurgitate misinformation and unwittingly spread hype. Be careful where you get your information! I've even met professional techs who honestly don't have a clue. Also, take everything your local GC guys say with a very large grain of salt.

What is Class AB?
Basically, the audio-practicality of Class A combined with the efficency of Class B. Hence, Class AB.

Which sounds better: Class A or Class AB?
It depends on who you talk to, but it depends more so on the overall design. The most sought after amps in the world are probably the tweed Fender Bassman, Marshall Plexi, tweed Fender Deluxe, blackface Fender Twin Reverb, blackface Fender Super Reverb, Vox AC30, Ampeg SVT, and Marshall JCM800. The vast majority of modern amps are simply clones of these amps, or are slightly modified versions (i.e. more features). I'll let you in on a little secret.. they're all Class AB! Dun Dun Dunnn! Yes, the Vox AC30 isn't Class A like it claims, but cathode biased Class AB that's biased on the hot side. These amps are loved because their overall design is good; it really has little or nothing to do with the class of their power amp.

The most famous Class A amp is probably the Fender Champ.

How can I be sure if an amp really is Class A?
There's one way to be certain: if the amp only has one (1) power tube—like an old Fender Champ. If there's two or four power tubes the amp is more than likely Class AB. We could make a slightly better guess at ruling out Class A if we have the amp's schematic, but to know for sure we'd have to break out a function generator, oscilloscope, and dummy load—then run tests. Another hint: due to their inefficency and heat generation Class A amps tend to be very low wattage (i.e. if the amp is over 15 watts it's probably not Class A).

[NeoFauve]

Is it me, or is just about every smaller EL84 powered amp you read about called "Class A?"

[Kap'n]

Is it me, or is just about every smaller EL84 powered amp you read about called "Class A?"

Yes. You can probably track it back to the Necrenomicon of amplication, Aspen Pittman's The Tube Amp Book.

[jeffhoo]

Yes. You can probably track it back to the Necrenomicon of amplication, Aspen Pittman's The Tube Amp Book.

i've read some criticism of that book and author onliine from time to time but very little beyond just one-liners. i'm not an amp builder, just a player so i don't have a sense of the historical context. what's the story (for us newbies)?

[Offshore Angler]

Why not use this?

http://www.voxshowroom.com/us/amp/beat.html

[Kap'n]

i've read some criticism of that book and author onliine from time to time but very little beyond just one-liners. i'm not an amp builder, just a player so i don't have a sense of the historical context. what's the story (for us newbies)?

Which, TTAB, or the Necronomicon?

Necronomicon is easy. It doesn't exist. Or it didn't. It was an invention of an author. Another author, sensing an opportunity in the market, created a fake one.

TTAB. Well, back in the dark ages of the 80's, when actual literature on amps was non-existant, a marketer named "Aspen" Pittman, who was head of Groove Tubes, sensed a hole in the market. With this, he 'wrote' The Tube Amp Book. I've never seen the first edition, but I'm guessing it's shabbier than the second edition, which I own.

The second edition book is essentially one continuous advertisement for Groove Tubes, sprinkled with factual errors, outright lies, a handful of tips from Ken Fisher (reprinted from an old Angela Instruments catalog - I miss those), and a bunch of schematics. The whole thing looks like it was written on a typewriter, with non-existant proofreading with pasted-on photocopies of pictures.

The really valuable part is the schematics, of which there were a considerable number, and were hard to come by in the pre-internet era.

I've also got the Third Edition, mainly for the schematics. It looks like was done on a word processor - one without spell-check, and has more schematics, some reprinted markeitng articles written by Pittman and a photo section. He attempts to date the amps in the photo section with often hysterical results.

Both of them, if you know anything about amps, are pretty funny.

However, I will give him this - he helped found the market for vintage amps, during the height of hair metal.

[Rickenjangle]

Why not use this?

http://www.voxshowroom.com/us/amp/beat.html

Are you gonna schlep it for me?

Remember when these things were cheap and undesirable? I wish I had bought a dozen. Then I could sell them for a huge profit and buy a boat from you!

[blackonblack]

[blackonblack]

This is from Justins HRD site.


How can I be sure if an amp really is Class A?
There's one way to be certain: if the amp only has one (1) power tube—like an old Fender Champ. If there's two or four power tubes the amp is more than likely Class AB. We could make a slightly better guess at ruling out Class A if we have the amp's schematic, but to know for sure we'd have to break out a function generator, oscilloscope, and dummy load—then run tests. Another hint: due to their inefficency and heat generation Class A amps tend to be very low wattage (i.e. if the amp is over 15 watts it's probably not Class A).

What I was trying to quote as

[jeffhoo]

thanks Kap'n for the lowdown on the "tube amp book". i just didn't have much of a perspective being new and that makes perfect sense.

[redcoats1976]

the lead guitarist in my favorite beatles tribute band uses a gibby les paul,and he sounds real good.