Weight vs Wattage vs Current vs Slam vs Value

Bipolars have more current delivery than Mosfets.
Separate power amp should have more slam since it's power supply is not being shared as in an integrated.
Krells "double down" in power but these type of amps typically loose high end sweetness for some reason.

All other things being equal (and they usually are not), a heavier amp will have more slam than a lighter one. In many cases, my experience is that a heavier amp is also preferred to a higher wattage amp. As an example, a pair of 200W Ampzilla monoblocs (about 58 pounds each) have much more bass controll than a bridged pair of 1200W Carver A760x (39 pounds each?). The reason is mainly the power supplies being used (about half the weight of the Ampzillas is the massive 2.5kVA torroid). The difference is most apparent on speakers that go below 4 ohm. Damping, feedback, etc can also come into play, but any good design has to start with a good (usually meaning heavy) power supply first.

Julian

Say Julian, how did you measure "bass control"? And, btw, you are a dealer of Ampzilla amps, are you not?

The older Carver M series amps, designed by Bob Carver, did not put put a lot of current and weren't as strong as their watt ratings suggested. But, the post-Bob Carver A series were high current amps designed for stability into any load. (I don't have an A-760, but I doubt it would have trouble controlling any speaker made.)

I was always curious about power supply design. For example, I have seen amps that happen to be very light, therefore, I must assume have similar LIGHT power supply design, one of this manufacturers being LINN. Their TWIN KLIMAX is so unbelievably light, and yet it seems to sport a very high wattage. How is this possible? Does this mean that the Linn amps cannot handle tough loads as the impedance drop?
What is the largest single transformer out there? 2.5 KV, is that the largest? If the transformer is too large, does that mean that it might be slow in releasing energy to the speakers? Just wondering....

PAUL

Hello PaulWP,
Yes, I am an Ampzilla dealer as well as a few other brands. Trying to post helpful information on sites like this is somewhat difficult for a dealer like myself. If I say that I am a dealer, I get flamed for "advertising". If I don't say that I am a dealer, I get flamed for "trolling". No-win situation. :-( I used the Ampzillas just because that is the "high weight" amp that I am most familiar with and have had an opportunity to A/B against many others.

My un-scientific measure of bass control is the initial impact and controlled decay of low frequency instruments (i.e., the thump of a kick drum or the initial twang of an upright bass). On a well controlled system, the initial sound should be distinct followed by a resonant decay. On an uncontrolled system, the initial impact is less distinct and the decay is more rumble than resonant. I once tried a 3 watt SET amp with one of my 4 ohm speakers and "bloated" is the word that best comes to mind. In this extreme case, the bass was so "loose" that it was somewhat hard to distinguish individual bass instruments (the mids and tweater sounded fine).

The Ampzilla/Carver comparison was done driving a pair of Martin Logan CLSs (a VERY difficult load). The difference in control was not subtle and something a non-audiophile could easily detect (no golden-ear required). I, as well as my customer, were somewhat surprised at the difference. Had the speakers been an easier load, I do not think the difference would have been nearly as distinct.

Bemopti23,
Wattage is primarily a marketing term somewhat like an auto manufacturer stating how fast a car will go. If you have an easy to drive speaker (i.e, steady 8 ohms) then it has some realative meaning (think Hona Civic driving 80 down a flat highway). If you have a hard to drive speaker that dips down to the 2-ohm range, then it means little (think Honda Civic trying to pull a 5 ton trailer up a mountain. aaaaugh).

The 2.5kVA torroid in the Ampzilla is very large but is still smaller than the 5kVA+ and dual 4kVA torroids in the higher-end Krell amps. I am sure there are even larger in some of the "specialty" amps. Several of the mega-amps require dedicated 30A circuits (wouldn't want to know what that would do to an electricity bill. ouch).

The released current comes from the capacitors (another part of the equation) so a larger torroid should not result in a slower sound. Since a larger torroid can better feed the capacitor array, the sound should theoretically be faster. I am not an amp designer so I will leave further discussion on this subject to those more knowledgable than myself.

Julian