tubes...

[CJ]

how much do tubes make a difference in sound. I'm talking about for my marshall 3203 artist which has one phase inverter tube (phillips tube from 1990 or 93 i was told, forget which) and two Svetlana EL34 tubes that i put in last year because i was told they were good. I have no clue if any of these are good tubes, and would like to know if i'd get a better sound by replacing some or all of them. I know that my tubes are technically fine, just wondering if an upgrade or change would help out. by the way, i think my amp is a million times too dark (could be guitar?), could use some more gain and heavyness.

[hamfist]

Having a solid-state pre-amp, you obviously have no pre-amp tubes to play with. Changing these often has the most obvious effect.
   You may achieve subtle changes by trying NOS EL34's (Mullards are excellent but astronomically expensive), or a new PI.
  However, I would suggest that you would gain much more radical changes by trying different speakers, or even a new cab (I'm assuming its a head).  It would be easy to try this out by taking it along to a decent shop and playing it through a few different cabs.
   What speakers are you playing through at the moment ?

Alan

[Elliot]

Normally power amp tubes need to be changed every year or so to keep optimum sound - Svetlana's are usually good tubes and replacing them with the same variety (get a matched pair) might add some more presence to your amp.  Groove Tube's Mullard remakes have got good reviews as well (haven't tried em myself).  

Going for a hi gain (like a 7025) Phase Inverter tube might also add a subtle difference as the Phase Inverter can be considered part of the power amp.  Whether it's necessary with a solid state pre-amp is another matter.

[froglord]

Watford Valves do reports on valve types that give you some idea of how they sound:

http://www.watfordvalves.com/reports.asp

[HTH AMPS]

i think my amp is a million times too dark, could use some more gain and heavyness.

More gain and heavyness eh? - I normally wouldn't use 6L6s in EL34 amps but they might just be the ticket in this case.  Get some JJ 6L6s as they're probably the toughest 6L6s on the market at the minute for handling higher plate voltages that your EL34 amp will have AND they sound very good too.

As for the PI valve, try an ECC81 in there - it'll give you more low end grunt, a slightly cleaner tone (less fuzzy) and more clarity than an ECC83.  Good news on ECC81s is that the NOS ones are still very inexpensive so go hog-wild and spend a tenner on a nice one.

Not to jump on Elliot or anything, but 7025s are specially selected 12AX7s that match a set of parameters based mostly on low noise.  Back in the day when Fender specified them for the first preamp stage in their amps, there really was a difference between 7025s and 12AX7s but these days I'd say not.

 :twisted:

[Elliot]

HTH, I bow to superior knowledge in these things.  I did know about the original 7025 classification.  I would add that modern production tubes called 7025 are normally tested ECC83s/12AX7s that are low noise and at optimum gain levels - at least that's how TAD and Harma (Watford Valves) class them, amd, I think, other re-sellers who call their tubes 7025 also do this.  They are not like the real GE 7025s that Fender used, rather the best of the bunch of current production valves.

I am interested that you recommend a ECC81 for the PI, I always thought you went lower gain in V1 and higher in the PI valve (I am a Fender amp man, and that seems to be the advice of Fender types).  I will try out your way, as it might give a different dimension to things.

btw - call.me nasty - if your amp is too dark it a sure sign that your power valves are passed their best.  I agree that JJs are good on this score.

[CJ]

i think my amp is a million times too dark, could use some more gain and heavyness.

More gain and heavyness eh? - I normally wouldn't use 6L6s in EL34 amps but they might just be the ticket in this case.  Get some JJ 6L6s as they're probably the toughest 6L6s on the market at the minute for handling higher plate voltages that your EL34 amp will have AND they sound very good too.

As for the PI valve, try an ECC81 in there - it'll give you more low end grunt, a slightly cleaner tone (less fuzzy) and more clarity than an ECC83.  Good news on ECC81s is that the NOS ones are still very inexpensive so go hog-wild and spend a tenner on a nice one.

Not to jump on Elliot or anything, but 7025s are specially selected 12AX7s that match a set of parameters based mostly on low noise.  Back in the day when Fender specified them for the first preamp stage in their amps, there really was a difference between 7025s and 12AX7s but these days I'd say not.

 :twisted:

excuse me for asking, but are there different brands of these ecc81's, or were you still referring to JJ tubes (if these are even a brand...)? i just did a quick ebay search and these came up at 5 bucks a tube http://cgi.ebay.com/12AT7-ECC81-Tube-Tubes-Shuguang-Chinese-NEW_W0QQitemZ220161728424QQihZ012QQcategoryZ64629QQssPageNameZWDVWQQrdZ1QQcmdZViewItem but i'm assuming thats way too cheap.

as for the speaker selection, sorry, i'm just looking for inexpensive solutions to improve my tone. maybe when i have more money i'll buy a new cab.

[HTH AMPS]

urgh, I'd stay away from Chinese ECC81s when you can get the likes of these at $9.99 a pair...

http://cgi.ebay.com/Pair-GT-BRITAIN-Amperex-12AT7-ECC81-Tubes-VF3-CODE-TEST_W0QQitemZ300164202678QQihZ020QQcategoryZ64629QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

or some JAN-spec (Military) GE's for £13.50...

http://cgi.ebay.com/GE-JAN-12AT7WA-6201-ECC81-NOS-tube-Brand-New_W0QQitemZ190156890885QQihZ009QQcategoryZ73378QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

or a pair of Tung Sols for $22.99...

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180157069117&ssPageName=MERC_VI_RSCC_Pr4_PcY_BIN_Stores_IT&refitem=180153603026&itemcount=4&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget

You get the idea.

As for using an ECC81 in the PI slot, this isn't really a 'mod' - Hiwatts originally used ECC81s in the PI slot as did Sound City and the classic Blackface Fender Twin circuit specifies a 12AT7/ECC81.  

I like to use them in high gain amps where you get more low end and the tone isn't as fizzy round the edges - it's cheap to try so go ahead and see how you like it, you'll also get more clean headroom on your clean channel.  

As for using ECC81s on the first preamp stage, I personally don't like it as I feel the amp sounds too flat, but that's just my preference.

 :twisted:

[CJ]

well i thought you were saying the ecc81's for the PI and two JJ6L6's for the power tubes... right? because the PI tube is way smaller than the power tubes so you couldn't interchange them anyway.

[hamfist]

as for the speaker selection, sorry, i'm just looking for inexpensive solutions to improve my tone. maybe when i have more money i'll buy a new cab.

Seriously, I still think spending a few bucks on a different PI and/or power tubes (unless your power tubes are shot) will really only give you a very subtle change. Tubes may cost less money than speakers but if they don't change things the way you want them to then it will be a waste of money.
  Anyway, one Eminence Wizard speaker (for example) or a used Celestion V30 or G12H30 would cost about the same as a new set of power tubes plus a re-bias. Even adding one new speaker to a 2x12 will really make a huge difference, if it has a very different character than the speakers you have at the moment.

  If we were talking about pre-amp tubes  it would be a different story, but we're not.
 
   As a blanket statement, I would say a speaker change can transform tone, whilst tube changes will only subtly change it, at most.

  It sounds to me like you need to establish whether your power tubes are shot. If they are it's definately worth replacing them. If not, I'd save your money. Has your tone deteriorated with this amp over time, or has it always been like it is ?

Alan

[Elliot]

For JJs in the US try this guy: http://www.eurotubes.com/

[CJ]

i understand that tubes won't really change my tone much, and that speakers will. but, seeing as how i have a 4x10, i'm not ready to spend the money on 4 new speakers. 2 might be a possibility, but not now. tubes were just a thought, maybe it'd liven up my tone a bit. really, i don't have much of a problem with my tone, but you know, if you can improve it, why not... maybe i'll wait off on the tubes. actually, does the phase inverter make any difference to the sound at all? in that case i might as well replace it seeing as its like 15 years old.

[Elliot]

How old are the power valves?  They would change the tone more than the PI.

[CJ]

a year or two. i only play the amp maybe once a week so i doubt they're due for a change. only was looking to change if maybe a different set could liven the amp up.

[HTH AMPS]

well i thought you were saying the ecc81's for the PI and two JJ6L6's for the power tubes... right? because the PI tube is way smaller than the power tubes so you couldn't interchange them anyway.

that IS what I'm saying.

 :twisted: