Pre-amp Tube Swapping

[Birdy]

I'm thinking of trying a couple of Mesa SPAX7 "high grade substitute" tubes
in my ED. Trying 2 of them for a difference in tone, I guess the typical V1 and V2
positions would yield the biggest(if any) difference as per most amps ?
Any one else swapping tubes(pre or power) ?

 

[Laskyman]

Love to hear the review....

 

[MrMarkIII]

The SPAX7s are chosen for low noise, not tone. They're good, but really don't sound better or different than the stock Mesa 12AX7.
Get a NOS Mullard, RCA blackplate, or JAN GE 5751. Or all three.

 

[JOEY B.]

I guess the typical V1 and V2
positions would yield the biggest(if any) difference as per most amps ?

Check pages 36 and 37 of your users manual for the tube task chart. Actually, V4 and V5 are for the clean channel, and would be first in the signal chain, if you follow the "adding preamp stages of gain" theory. I just loaded mine up with 1960's tungsram in V4 and V5, and RFT in V1,V2 and V3. The old MESA STR-442 (SED Winged =C=) EL-34's in the power section for now. 8)

 

[Birdy]

I guess the typical V1 and V2
positions would yield the biggest(if any) difference as per most amps ?

Check pages 36 and 37 of your users manual for the tube task chart. Actually, V4 and V5 are for the clean channel, and would be first in the signal chain, if you follow the "adding preamp stages of gain" theory. I just loaded mine up with 1960's tungsram in V4 and V5, and RFT in V1,V2 and V3. The old MESA STR-442 (SED Winged =C=) EL-34's in the power section for now. 8)

Hey Joey B.
How big was the tone difference going to EL-34s ?

 

[JOEY B.]

Hey Joey B.
How big was the tone difference going to EL-34s ?

With the stock preamp tubes, I tried the ED with a quad of STR-450's. The tone was a bit different, but did not change the overall sound greatly. I do not feel that the cleans suffered much with the EL-34's compared to the 6L6's. It did require a little change to the gain setting to make the EL-34's clean up nicely on channel 1. Beyond that, maybe a little less bass, fatter mids, and smoother highs with the EL-34's compared to the 6L6's. But then none of the tone controls were at their upper or lower limits, so there is definately room to tweak.
8)

 

[Assumer]

I really should try some 34s. Problem is, it sounds so good with the 6s I can't imagine anything better.

 

[JOEY B.]

I really should try some 34s. Problem is, it sounds so good with the 6s I can't imagine anything better.

I wouldn't say "better", but I will use the word "different". :wink:

 

[gplex]

What a great amp this ElecrtaDyne turned out to be. It has G.A.S (great amp syndrome). It sounds so good no matter where you set the knobs and is easy to coax out a lot of different tones... quickly.

I played this amp for a week, then remembered... Hey I can try 34's too. I usually am trying tubes right off the bat. I'll stick with the stockers for a while longer, I like the sound very much. I have the combo and have a Jensen Jet Blackbird coming my way. I have had the bug to try one for a while now and think the darker nature of the Jensen will compliment the brighter nature of the ED.

I may then try some pre's. But man this thing is pretty much perfect as is, but like most of us I think I can take it to the next level.

Hey JOEY B. what did the pre's you mentioned do for you? I was actually thinking of some JJ's. I usually don't like them in mesa's but seem's they might be a good fit for this.

 

[JOEY B.]

Hey JOEY B. what did the pre's you mentioned do for you? I was actually thinking of some JJ's. I usually don't like them in mesa's but seem's they might be a good fit for this.

Your ED came stock with re-labeled JJ preamp tubes. The NOS tubes have a much lower noise floor, and better articulation in the clean channel. The Vintage Low channel is awesome with the RFT preamp and EL-34 power tubes. 8)

Here is a link for the preamp tubes: http://www.tubemonger.com/SearchResults.asp