How loud is a JTM-45 (2x12" combo) compared to a 40W Fender like the Vibrolux?

The thing is I've never played a SF Vibrolux Reverb 2x10. So we have no point of reference! Does it help you to know that a JTM45 puts out about 33 - 35 watts of power? If you have two Greenbacks in the cabinet it makes quite a bit of difference than if you have two Blues (the Blues are louder).

Scientifically there's not a lot of difference between 33 and 40 watts.

Anyway until you come across someone who owns both I trust this helps a little.

Best, Pete.

 

I haven't done a direct comparison, but expect the stock Celestions in the Marshall would be more efficient (and hence louder) than the stock speakers in a VR.

The speakers will be the main differentiating factor. If you plug the two amps into the same cab, they'd probably be about the same overall perceived loudness, though there may be differences in the amps' respective abilties to "cut through"due to differences in frequency response, distortion characteristics, etc.

 

If the BB has Greenbacks, it won't be as loud. A greenback can take alot of volume out of the equation.

 

Speakers do make a huge difference, but in general:

The Fender puts out a true 35w RMS clean, the Marshall puts out 35w but it's already distorting. Plus 6L6s have a harder attack than EL34s. So, they make a pretty good match, but the Marshall will likely be overdriving sooner than the Fender. You can get them closer if you use KT66s or 6L6s in the JTM45.

 

Okay, in my experience now:

Had a buddy that used a Fender Vibrolux Reverb RI for a long time, heard him play the amp a million times at the same club with the same band.

He tells me he wants to borrow my JTM45 RI (with KT66's and other vintage mods) and 1966 Vox 2x12 cab for a gig, so I grant him his wish. The JTM45 was much "sweeter" in the mix, and just tended to "push itself through" better than the Vibrolux. He also agreed that it was no comparison, that the Marshall truly cut through better with better bass response, and a fuller sound overall.

In my opinion the Marshall isn't necessarily louder, but somehow, it positions itself better in the mix. But of course this is talking about reissue pieces, I have no experience with original JTM45's and only limited experience with vintage Vibrolux Reverbs.

 

Just FYI, the Fender Vibrolux Reverb RI (really called the Vibrolux Custom Reverb) has NOTHING to do with the SF Vibrolux. It isn't even in the same class of amp IMO. I used to own the the Custom and currently own the SF Vibrolux ('70). The SF is a head and shoulders better amp. I have however no experience with the JTM-45. The ones I have heard have been great sounding darker tones. This isn't to disparage the Marshall at all, actually I would love to own one and have been jonesing for one for some time, but the SF Vibrolux is a VERY bright amp and my guess is the Vibrolux would cut through a mix at a much lower actual volume than the darker Marshall. That isn't to say that one would sound better to you than the other, given the subjectiveness of tone and all. But a Vibrolux cuts very well in a crowded mix.

 

The Bluesbreaker is much louder, regardless of its speakers. If you ran them both together you'd have a hard time hearing the Vibrolux. A Vibrolux Reverb really isn't that much louder than a Deluxe Reverb.

 

I have access to both a Vibrolux RI and a BB. The Vibrolux is louder, but the BB sounds better. Neither sounds as good (or loud) as a Vox.