What makes a good tube amp a good tube amp and bad tube amp a bad one?

[Alan0354]

Thanks for your answers So people building amps really just have to experiment with different parts and layouts to get the sound they want?

There are theory behind layout. Also experienced people know how to layout the components and wiring to get the best sound without even get into theory. Electronic theory will help you in designing something safe, something that is reliable and stable. Beyond that, there is a lot "MOJO" and very little electronic theory involved.

When the amp is designed wrong electrically, it would be obvious........like smoking if you over stress components. Sound motor boating, squealing and really sounds funny. These usually cause by oscillation, ground loop, cross talk etc. An amp that design correctly according to theory can sound lousy!!! That's where the mojo take over.

Bottom line, you need basic electronic background, then you need to learn the mojo!!! There is no right or wrong components, it's how you put them together. Mojo is actually the hard part in my book. Sound is so subjective, there is no right or wrong. That's where it really gets hard. Also, the major components of sound are the speaker and cabinet. That is usually beyond your control other than experimenting to find the right one!!!! And that can be costly to experiment.

[walkman]

Ok yes it is subjective of course. However there is only one aspect that I can think of that is not as greatly subjective as playing style or genre of music to the amplifiers usefulness to the user.

Fit for use - is it built in a fashion that will last wear and tear.
( Peavey has an excellent reputation for this for example )

I would argue that quality of workmanship in regard to the production of the amplifier will generally produce a 'better' amplifier than otherwise. Likewise that goes for the for lack of a better word integrity of the design.

That's not to say other amplifiers may not be pleasing to the owner.

My 2cents

[Chuck H]

Just look how many posts pop up for older Peavey gear!!! Who actually WANTS to play through a TNT 80 watt bass amp??? But guess what.?. They're still out there after decades of abuse! And, JMHO, modern Peavey products are some of the most useful and competitively priced amps made! This pleases me to no end since much of their product line is still made in the US. Proof that we CAN compete! A scratch start might be tough, but Peavey is proving that it's possible. Excellent!

[Justin Thomas]

If I turn it up loud enough, most Peavey gear I play sounds from good to great. And I guess one criteria, depending on where you are socio-economically, is: a good amp is one that gets you through gig after gig after gig reliably and keeps you paid & putting food on the table. I think PV has earned their spot there...

Re: sound guys- my usual experience...
"Can you turn down your stage volume? If I mute you in the house, it doesn't make any difference."
"If you mute me ij the house, how does it sound?"
"Fine. It's s present, filling the room, and sounds good."
"Is it covering up vocals or drums?"
"No..."
muttered under breath: "then my amplifier is doing its @#$%ing job!"

Justin

[walkman]

I've owned 3 peavey amplifiers, 1980's encore 65, 1990's classic 4x10 and currently have an 2000's studio pro 112 as practice amp. All of them second hand all great value for the price I paid. All sound good

[Gingertube]

Oh Oh - Drummer Jokes:
"How do you tell if the stage is level? - The drummer is drooling out both sides of his mouth".
Sorry - could'nt resist.

Many years ago when I was still an apprentice (early 1970's), in the evenings I used to be the 2nd roady for a local band with a big PA (1000W a side stereo, big for the day). About half way through most gigs the main guy who ran the desk too, would fall off his chair at the mixing desk due to alcohol intake and I would take over. I would immediately turn the compressors down and the power amp masters up, the actual sound level would come down and clean up hugely. He seemed to be of the view that compressing the signal to the power amps and running them at lower master settings would protect the speaker stacks. I could never get him to understand that when you turn the signal into square waves the average power goes way up, the sound goes to mud and the speakers are actually dissipating MORE power and running hotter. The concept that clean peaks were easier on the speaker stacks than lower level square waves was something I could never get across to him. He "knew" better.

Cheers,
Ian

[Chuck H]

That's a good drummer joke

Your sound guy must have been working from experience. He probably had a speaker blow a time or two due to a peak of some kind and found that compressing THOSE peaks saved the speakers. Failing to take all the technical aspects into account (you did mention copious alcohol consumption). Some of the old timers do know a lot of valuable and practical things to apply. Others THINK they're "that guy" just because they've gotten by in the same line of work. Having learned almost nothing technical. This isn't exclusive to any particular occupation. And you can't generally teach guys like that anything.