50 vs 100 watt amps....

[Gravityfield]

  A couple of killer deals  on tube amps have come up for sale in my area, and I need to make a decision.
One is 50 watts, the other 100.
 
My question is does a 100 watt amp have something, even at lower volumes and using a master volume or attenuater, that a 50 watter does not have?

Bass response I am thinking possibly?
 
 I have heard 100 watt amps described as having a certain "thump", that 50 watt amps simply cannot reproduce.
One thing I am trying to consider is that the places I play at certainly do not require 100 watts, but I would hate to get a 50 watt amp and not be happy with the immediate compression.
 
 I plan on using either of these amps with either an attenuater or post phase inverter master volume.
Thanks for insight.

 

[simple]

+1 for the 100 watter. In my experience it does provide the fullness (thump) that you speak of.

 

[jackthehack]

It help if you mentioned which "killer amps" you were trying to compare?

If you're referring to tube amps and "real" wattage ratings the difference between 50 and 100 watts in SPL terms is only 3 dB.

Overall amp design - especially pre-amp stage - features/controls/speakers would impart a lot more importance to me than strictly the wattage rating.

 

[Gravityfield]

Jack-
Sorry man, I meant to say killer "deals" on amps, although the amps are pretty decent also I'm sure.
One is a replica of a 50watt Marshall (no master volume) and the other is a 100 watt Marshall  Superlead reissue (with some sort of master volume, possible post phase inverter in one of the input holes)

 

[jimh]

I'd take the 50W, but then I've got one.  Mine is a Ceriatone clone.  See if you can find out who made the clone.

 

[jackthehack]

Which "replica of a 50watt Marshall"?

 

[Justinginn]

As much as a cranked non-master amp blows everything else away (  :headbang1: ) I doubt you play lout enough to get any drive at 50 watts with no master. The 100 watt might end up being better... In general on this forum you'll hear that the more you can crank up the amp the better, hence the 5 watt amps people are starting to buy that aparrently sound good. The good Rock sound is basically summed up by clipping power tubes and at 100 watts it's pretty hard to get them that loud so in general I'd say louder is better unless you play arenas un-mic'd. But, since it's only a 3 db difference anyway, the master volume might help you keep it playable.

 

[-CB-]

Just a few things.... on amps. :icon_smile:

Keep in mind that the volume difference between 50w and 100w is not that large.  Doubling the wattage give you about a 3db increase in volume, which our human ears can fully differentiate, but... just by saying "yah, that one is louder than the other".  Its not a huge volume difference. 

Keep in mind that speakers make a huge difference in volume and also in transient response.  Typical speaker efficiencies run from about 91db up to about 99db and then up to about 103 or more db for Neo-magnet speakers.  If we're talking a 99db efficient 50watter vs a 91db efficient 100watter, the 50's gonna blow it away and then some.  Put 103db efficient speakers in the 50w'er and it will sound fully twice as loud as the 91db 100w'er.

Transient response is generally better on 100w amps - at the same volume and power level as 50w amps.  There are two reasons for that.  One is the output transformer iron.  There's more of it in a 100w output transformer.  A transformer converts the AC current to an electromagnetic field (in the iron windings) as the field collapses, it drives the output of the transformer.  Overly simplified... but there is more to collapse, collapse more efficiently when the 100w amp is loafing on 4 and the 50w amp is pushing 7 on the dial to maintain the same volume.  The other reason is also due to transformers, but its the power transformer.  It works less hard, and again, it has a bit of electromagnetic force in reserve for those thumps (low freq transients).  Now keep this in mind - if you drive the 100watter as hard as the 50watter, making it louder than the 50, then its going to lose that reserve and begin to mush up a bit, just like the 50 did (but at lower volume level).

Speakers and transients - whoo boy... this starts to get into efficiency and coil gaps.  More efficient speakers will make better use of power, and take less power to do the same job.  This will let you drive the amp less, keeping the amps power down and increasing the transformers response to transients.  So you get a bit of double boost by running high efficiency speakers.

The loudest amp I've ever owned was my early 70's Super Reverb, when it was loaded with Celestion Vintage 10's.  Would wipe any 50 or 100 watt amp up.  But the best thumper I've got (or at least working right now) is my Twin Reverb, which... pretty much wrote the book on clean and powerful.  Showman and Dual Showman amps are pretty much the same, or a little better at thump and transients.

That probably doesn't mean much in terms of the amps you're looking at... but... thought I'd add it just the same.

 

[mullyman]

You know, I can't get all technical with you on this but I have a 50w Mesa Single Rectifier combo and a 100w Dual Rectifier head. One time I had the head out for service and had a gig to do so I took the 50w combo with me and ran it into a Mesa 4x12 Road King cabinet. In all honesty, from that one experience, I've decided to get rid of the head but have been lazy putting it up on auction. As for the combo, it weighs a ton so I'd like to sell it also and get the 50w head version. There is more than enough power and plenty of ass in that 50w amp that I really don't need anything more than that.
MULLY

 

[jackthehack]

To reiterate one of CB's points, I don't think I've been onstage with anything louder than vintage Fender Super/Twin reverbs with JBL D-series speakers.

I really need to break down and spend whatever it takes to buy some mint vintage D-120s and find somebody in China that will replicate them for cheap with child prison slave labor....

 

[-CB-]

Yah, those, the EV-Force and the Vintage 10's.  All great speakers that you cant get.  Put me down for a brace of those JiBuhlaLi speakers.