Slam possible with Tubes instead of SS ??

You can get slam with tubes. I have 1 watt Serious Stereo monoblocks that have plenty of slam with my highly efficient Altec 604 drivers. These amps though are more than your price range. As far as system noise the Serious Stereo 2A3's do have a small bit of tube hum. This could be mostly eliminated by humbucking resistors which most manufacturers put in their amps. The problem is that there is no way to eliminate hum noise without taking some of the music along with it. Serious Stereo feels the trade off is not worth it. I have to agree as these are the best sounding amps I have had in my system by far. Once the music is playing you do not hear it. I have addressed other noise related issues though and must say that controlling the ground on your system is an incredible upgrade. Audio Magic makes a ground disrupter that eliminates ground noise throughout your system and it seems to really work well. There are other similar products out there and it is worth checking out.

Going along with the orginal question, how much difference is there between solid-state rectifier vs. tube rectifier in a tube amp when it comes to bass slam (quality).
Thanks

Ladies:

I asked Snell this week what they recommended for these speakers and they said many (employees) had good success with Bryston 501 monoblocks. Apparently the woofers are wired as to demand a lot of current. So, does anyone know about these monoblocks?

hi rrog:

i have quad esls. i have used a variety of tube amps, including the quicksilver mid monos and the vtl delxe 120s. i think quads, sound less fatiguing with a classic tube amp, such as one of the older cj amps--mv 45, mv 75, mv 100 or mv 125, than any ss amp.

i have been looking for a ss amp, to extract more nass extension and impact. i have auditioned a couple only to be dissatisfied with the uperr midrange and lower treble frequencies.

i also own magnepan 1.6s. again using some ss amps, my objection to them mirrors my experience with that of the quad esls.

i should also mention that i owned the quad 63s, using my vtls and again seeking a ss amp. i again found the very same problem i experienced with the magnepan and esl, when interfacing a ss amp with the 63.

i am beginning to conclude that quads and ss amps create frequency response anamalies. it sounds like clipping, but i'm not sure why there would be a problem with quads, ss amps and higher frequencies.

is there some explanation ?

Mrtennis, yes and I think I have mentioned it before. ESLs have high impedance at low frequencies and low impedance at high frequencies.

Transistor amplifiers double power as you cut the impedance in half, which is another way of saying **their power is halved has you double impedance**. The ESL 63 has an impedance of 45 ohms in the bass. Your typical 200-watt transistor amp can only make about 40 watts or so into this impedance, and Quads actually *do* want some power.

By contrast a tube amp looses far less power into these higher impedances! Consequently only the bigger transistor amplifiers can keep up with a tube amp on a speaker like this.

The frequency response anomaly is related. First off, ESLs are a Power Paradigm technology. That is to say, since they do not have a box and associated resonance, they are not expecting that the amplifier be capable of constant voltage. see
http://www.atma-sphere.com/papers/paradigm_paper2.html
for more information.

Since the amplifier cannot make much power into high impedances and since it also wants to make a lot of power into low impedances, most transistor amplifiers will have a tilted tonality favoring the highs when used on most ESLs. The use of feedback helps reduce this problem, but does not eliminate it, and since the use of feedback makes almost any amplifier brighter, there is no good fix for it except to avoid transistors with ESLs.

Most ESL manufacturers want their speakers to work with transistors because its a bigger market, so you see a number of them making ESLs (Quad, excluding the 57 and 63, Martin-Logan, King, Innersound) with very low impedances to try to get around this problem. Its not a good solution though so even if you have one of these speakers you will still hear this phenomena with transistors.