I need more power!

[SunnyBoy]

Before I start, this is what I use:
*Solarus
*Marshall half cab
*Boss Metal Zone MT-2 or Diamond Fireburst
*Ibanez RG1570 guitar

So, I bought a Sunn Solarus about 7 years ago.  Loved it, but the guy said the tubes were nearly shot.  Well, I've been playing on it casually since.  I recently decided to make it my main amp and so I bring it to a shop to get it completely revamped.  After they replaced the two prong AC with a three prong, they said I didn't need new tubes yet so they just kept the old ones in there.

My problem is this, however:

I have awesome tones at bedroom level, but when I bring it infront of my band it seems like I just don't keep the same tone when I crank the volume.  It gets kinda weak. Could this be because we were playing in a rather small place and the sound was bouncing off eachother?  We just booked a bigger rehearsal studio so  I haven't tried it yet in a larger area.  I play anything from metal to punk.  Currently in a horror punk band so I don't need the blazing distortion, I just need to preserve my tone at higher/gig level volumes.

It just seems that it gets slightly weaker when I turn the volume up around 5 or 6 and lose my lush, rich tone that made me love this amp in the first place!

Help or advice?  Do I need to tweak my pedal or is it the amp?  Speaker?  I don't have access to the studio every day so it's hard to sit there and find the perfect combo when we have other things to do on our alotted slot.

[loudthud]

What impedance is the Marshall cabinet? There originally was a label by the speaker jacks on the amp that usually says what impedances the amp will drive. If things don't match up, the cab or amp can be modified.

There are two versions of the Solarus. The 40W version used EL34 tubes and the 80W (1970) version used 6550 tubes. There should be a paper label on the inside left (from the back) of the head box that tells what tubes the amp should have.

[xsolarusx]

Have you tried dialling in your 'sound' at higher levels?  I found that my Solaruses(both 70's models with 6550) are plenty loud and retain the sound I want at a variety of levels.

Hopefully it's something as simple as an impedance issue.

Ohh, and Loudthud, I was always under the impression that the later Solarus amps were 60w, but 80w would make sense, as they're on par with my Traynor YBA-1A for output.

[loudthud]

I got the 80W from the catalog thread. Basically, the circuit was the same but I'm pretty sure that model had a solid state rectifier in place of the GZ34. I have several YBA-1As and they tend to burn up EL34s unless you bias them on the cold side. It takes a really strong pair of EL34s and they don't maintain performance for very long. 6550s IME last longer but don't produce as much power from the start in the YBA-1A.

[Ryan Phelps]

Did the shop check your power supply? Your symptoms (loss of power and mushy tone) can be caused by old filter caps that can't keep up with the current demand of the output tubes at higher volumes.

Ryan Phelps

[pickinatit]

I have a 40 watt Solarus and I can't even imagine having the volume up to 6.
It has 25 yr. old Mullard EL34's in it.
I only remember ever having the volume past 4 twice in it's whole 40 year life.
Once was playing an outdoor pool party back in the day. I cranked it to 5 and was told by our manager that I needed to turn down.  Once about two years ago I cranked it to about 6 "just to see"  and I thought my ears were going to start bleeding.
That was playing thru the original 2 X 12  cab w/ Sunn Transducers that came with the amp.

[xsolarusx]

Well, I think your ears were probably about to bleed because your brain knew it could still go louder, and probably should.

Just saying!