.50 Caliber + losing "attack" whe turned up loud..

[Sludgenutz]

I just got my first Mesa, and I like it very much.

I have already replaced the worn STR-425 5881's with a pair of STR-440
6L6 (yellow group). The preamp tubes are Sovtek 12AX7wa that came with the amp. The sound has improved, but when the amp is turned up and a chord is strummed...the attack of the chord is delayed (muffled), and rises (blooms) to match the level it should have been when first plucked.

I am plugging straight into the amp, no pedals, and the speaker is an EVM12L in an open cab.

Thanks in advance!

 

[LHanson]

Bloom = good!

Are you reducing the preamp gain when you turn up the amp? Bedroom volume gain setups rarely work at full honk. A Boogie is almost an intrument unto itself, so ya gotta tweak the knobs.

 

[Sludgenutz]

You may be on to something. My amps pre section is loaded with four Sovtek 12AX7wa (I am reading these are rather bland), and I put in an unidentifiable Chinese or Indian 12AX7a (from a small, old gawdawful Crate hybrid combo), and the clarity/sparkle jumped enormousely.

Attacking the preamp section with a new set of tubes is the next step, suppose...as well as the suggested knob twisting (and that costs nothing!). I was just wondering if this meant dry caps in the power supply, by chance. Thanks!

 

[LHanson]

You may be on to something. My amps pre section is loaded with four Sovtek 12AX7wa (I am reading these are rather bland), and I put in an unidentifiable Chinese or Indian 12AX7a (from a small, old gawdawful Crate hybrid combo), and the clarity/sparkle jumped enormousely.

Attacking the preamp section with a new set of tubes is the next step, suppose...as well as the suggested knob twisting (and that costs nothing!). I was just wondering if this meant dry caps in the power supply, by chance. Thanks!

No expert, but I have recapped an old Fender, and PS caps will usually make the amp hum. It sure got quieter afterward.

Swapping and buying preamp tubes can be the road to nirvana- or insanity!

 

[Sludgenutz]

Well, I do believe you are right! I think I was just "winding" out the amp, like one winds out a new sportscar.

Dialing in a Boogie takes time as they say, and I was not actually able to repeat the "prob" I was having. What that really means, is that I stopped diming too many of the amp's gain/eq for a combination that sounded like crap.

Being less agressive with the preamp knobs opened up a whole new world. Of course, you guys know that already. I am used to my one-dimensional dinosaur Sunn model T that relies on a pedal to finish the tonal picture. My purpose was to buy an amp that needed no extra pedal to goose the input tone, and this Mesa is darn near perfect!

Thanks again, LHanson!

 

[LHanson]

Well, I do believe you are right! I think I was just "winding" out the amp, like one winds out a new sportscar.

Dialing in a Boogie takes time as they say, and I was not actually able to repeat the "prob" I was having. What that really means, is that I stopped diming too many of the amp's gain/eq for a combination that sounded like crap.

Being less agressive with the preamp knobs opened up a whole new world. Of course, you guys know that already. I am used to my one-dimensional dinosaur Sunn model T that relies on a pedal to finish the tonal picture. My purpose was to buy an amp that needed no extra pedal to goose the input tone, and this Mesa is darn near perfect!

Thanks again, LHanson!

Glad to be of help.

FYI, if you haven't already, if you search this forum for .50 caliber and other variants (50 cal, .50 cal, etc.) you might mine a few nuggets.

Enjoy your Mesa, and welcome to the board!