A guide to choosing tubes and cabinets!

[lsp1967]

Thank you "powerfreak" for the very good infos !!!!!!!!! ive printed 'em all !

Ill share my experience with tubes to date, maybe someone could use it.

First my equipment: 2x Marshall SLP reissues ( with mercury magnetics trannnies and chokes) , 4x 1960 AB cabs loaded with Celestion 80 watt neo's , 1x Eventide H8000A in the fx loops.

My conclusions.....

MHG set from GT ? not good
GTecc83s from Gt? not good,terrible.
GT SAG mpi phase inverters ? not good.go quickly (panic, thin sound).
GT12ax7m ? very good.GT12ax7m ? very good.GT12ax7 r3 ? very good
GT 12ax7r2 ? havent tried 'em yet

Gt6CA7ge's very good,damn good !!!! But...2 sets blew and were replaced by GT (here in europe our warranty lasts longer than in the states,be careful,and watch out for those mikes ! Preamp ? gimme that tubetech !)
[ I spoke to the head tech at Groove Tubes in the US, he says the GT-6CA7GE likes to run on a bias current of 40ma with a bias voltage of between -40vdc and -42vdc ]

I am currently fixin to try the GT 6550 R in one of my plexi reissues, for a side by side compare to the GT6ca7's, perhaps ill get back later.....
[ MARSHALL EL34 to 6550
1.) Change the bias resistor to 47K (located above the bias pot).
2.) Set the bias pot to max (around –38 volts)
3.) Locate the purple feedback wire (that is connected to the 8-ohm speaker tap) and solder it onto the 4-ohm speaker tap.
4.) Install the 6550’s and re-bias the amp. ]

Marshall sent me chineese peamp tubes as replace, TERRIBLE. They sent svetlana golds as power replacements, okay, dont compare to GT6ca7.
Stock power tubes chineese ruby EL34Bstr, terrible.Stock preamp tubes, terrible.

P.S. those celestion centuries (80 watts) are very good !!

[guitarshredder7]

this is a good thread i read it all

[Ant1981]

Ok dude, so what should I put in my JCM 800 to give it more of the sound of my JCM 900 SL-X?

[NNS]

Just a point on the psycho acoustics thing...

I reckon one reason that amps sound different at different times is your position relative to the amp...sound loses energy very quickly, and where you are will affect the way you hear the sound, as well as the way the room is arranged as this affects absorbance/reflection/refraction and diffraction. There's more than just electronics to take into account, acoustic physics is important.

Psychological factors do affect it a bit though, if you're in a creative mood you will likely be concentrating more I suppose so it could sound 'different' in a way. You can't say that it's all psychological though as I have heard that some people can tell teh difference between different types of violins and other instruments just by listening to them AND GET IT RIGHT, they would surely have to be psychic to do that if it was all psychological.

[Jaden]

Originally Posted by NNS

Just a point on the psycho acoustics thing...

I reckon one reason that amps sound different at different times is your position relative to the amp...sound loses energy very quickly, and where you are will affect the way you hear the sound, as well as the way the room is arranged as this affects absorbance/reflection/refraction and diffraction. There's more than just electronics to take into account, acoustic physics is important.

Psychological factors do affect it a bit though, if you're in a creative mood you will likely be concentrating more I suppose so it could sound 'different' in a way. You can't say that it's all psychological though as I have heard that some people can tell teh difference between different types of violins and other instruments just by listening to them AND GET IT RIGHT, they would surely have to be psychic to do that if it was all psychological.

yea, weve all had those gigs where nothing sounds right and you try to "force" it !!!

there is some serious technical knowledge available in this thread and while I may understand some of it, I cant help thinking about its true "value" when it comes to buying a new amp or getting it re-valved at your local shop....

Im looking at it like this...
you buy an amp - mess about with it and get the sound you want.....
when it starts sounding crap you take it to a shop..
they fix it up with new valves.....
it sounds good again...

TBH im only playing devils advocate here as I do all my own maintenance..
so what am I getting at?

well, I think you can "worry" over your equipment only so much.... when there is much to worry about on your actual instrument...

anyway, im gonna buy a carvin V3 soon, im sure that one of you very clever valve guys (at 15 !!!!! damn im stoopid!) could tell me why this would be a bad idea but.... im gonna get it anyway and im not gonna worry about it....

but its nice to know that you people are out there !!! especially when I need to revalve my V3

awesome knowledge......

[PortCityMusic]

Hello everyone. I am a new member here an thought I would add some additional information regarding tubes on this thread. Power Freak has helped everyone out regarding tubes and what may work in your amp and so on. I thought I would share some information about how you know when a tube is bad and may need to be replaced.

Replace the tubes when:

* It is broken, and/or there is a white spot on the top or sides of the tube.

* The "getter" coating found in these areas is normally black or silver colored.

* It tests weak or shorted. Always replace a shorted tube, even if it tests good. Shorts can damage expensive amplifier parts. You cannot afford to lose your amplifier during a performance. Professional players minimize downtime by replacing the power tubes every few concerts. The price of tubes is cheap compared to the embarrassment of losing an amplifier on stage! The amplifier starts to sound bad, especially when first turned on.

So how do you know when tubes are starting to fail? Consider the following: Small-signal (preamp) tubes (12AX7, 12AU7, 12AT7.): You may hear a crackle for a short time after the amplifier is turned on. Then it quiets down. Or the amplifier may "howl" at high volumes, or buzz on certain notes all the time. These problems get worse, and eventually you will be replacing one or more tubes.

Power tubes (6L6, 6V6, EL-34, 6550, etc.): Upon turning on the amplifier, the sound may be hazy, with flabby bass and scratchy treble. After about five minutes of this, the sound starts to clear up, and the amplifier sounds fine from then on. As the tubes get weaker, it will take longer for the sound to clear up. Eventually you have to replace the power tubes as a set. For reliability we strongly encourage you to replace all power tubes at a time, even if one or more tubes are still good. Rectifier tubes (5Y3, 5U4, etc.) are not in the signal path and do not affect the sound as much. However, if you notice more distortion than normal when playing at high volumes, the tube is probably half-dead and should be replaced. Tube Matching Please note that we are talking about matching power tubes such as 6L6, 6V6 and EL-34. I can tell you from long, hard experience that matching power tubes affects the sound of your amplifier. Compared to random tubes, an amplifier with matched tubes will provide slightly more power and a reduced hum level. In most cases, the improvement in sound quality will be slight, but worthwhile.

Rectifier tubes (5Y3, 5U4, etc.) are not in the signal path and do not affect the sound as much. However, if you notice more distortion than normal when playing at high volumes, the tube is probably half-dead and should be replaced.

Thanks.

PortCityMusic

[ChopTart]

Thanks for the info PCM - good stuff to have on this sticky thread

[rummy]

All tube amps of mine gets JJ/Tesla. I think they're the best sounding cost-effective tubes of modern days. EL34L makes my Laney and Carvin happy.

[satchbooger]

Mesa has told me that you can use any brand of tube as long as the bias rating
is 4, 5 or 6. 5 being the best match

-Keith

[Active 80's]

I didn't read any of it, but i bet you will like the bandit 112 peavey most! on a 4ohm cab 100w. the preamp its self is 300w. best gain, best modern metal, best vintage, best blues, and pretty dam good clean, that ive played and ive played quite a few (mesa triaxis has a little beter sound, but costs so much more that its just not worth it!)
ive played:
marshalls, voxes, mesas, krank... peaveys, fenders if you name it ive probably played it. line sixes (cept for vetta) kinda Suck... their pedals are pretty good tho.

[Thomas Welch]

I know this is an old thread but I took the time to read it and I must say I learned a lot. Very good job Power Freak.........thanks.

[losgatosrg350dx]

as much factor opinion this doesnt make sense to someone who doesnt know

all i can say is if you havent had the chance to experiment and try them all out, youll never be sole on taking advice, go and rent different amps, and different tube compliments, and see what u like, obviously if u play softer one type is suitable and if u play harder another type is also suitable

[Yousef]

Hey guys!

I just made the switch to an all tube amp. I got a Peavey Prolwer from evil bay for $230.
So far, it defenitley sounds better than any solid state amp that I've played. Way more sustain, warmer sound and doesn't sound shrill at high volume levels.
I'm loving the clean tone of this amp and even the soloing tone, but I really do enjoy playing metal type music, and the distortion at full on this amp gives me a low gain 80s type metal distortion tone. I'm getting a tube screamer today and this will probably fix the problem, but this amp seems old and I'm thinking I need to replace the tubes.

So my question is, what tubes should I use to get the most gain out of? This amp has 3 pre-amp tubes and 2 post tubes. The 3 pre-amp tubes are marked 12AX7 and the 2 post are marked 6L6GC. Also, whats up with the "soft, medium, hard" selection when I go to buy a tube? lol. Sorry for the ignorance.

[Bowie]

I just noticed this thread. I sell tubes and have an extensive knowledge of vintage tubes so, if there is interest here, I will post a guide to vintage tubes. They differ from modern tubes in that vintage tubes usually have better detail, dynamics, saturation characteristics, musical harmonic overtones, extended high frequencies and deeper bass. Vintage tubes vary widely in sound depending on the brand, year, construction, etc. You can also hit me up at ProAudioTubes@aol.com. But, I'm not trying to plug my business, I'd like to help people with tube questions as tube gear is a passion of mine.

I see there's already a lot of good info in this thread regarding compatibility and gainstaging.