Amplification for Wilson Watt Puppy 7s or 8s

Atmasphere,

In my conversations with Wilson, they currently use Spectral amps to design their speakers. Don't know what they did in the past. Wilson also said that because the WP8s dip to 2.3 ohms at 80 Hz, they will certainly benefit from a high current amp, especially if you like some high playback levels, which I do entertian on occasion.

The McCormacks are sounding better, as they only have about 20 hours on them now. My Wilsons now have about 100 hours, so they are loosening up, as well. Bass is getting better. Ray Brown Trio has such a deep organic bass, solid, tight, yet punchy with great low-end resonance. Piano is also fantastic. I don't notice any glassy highs on the 750s, just the contrary. Very smooth and maybe forgiving at the top, though, Cymbals may not have the last word in detail, and vocals may not be as silky smooth as I remember the Spectron, when running 4 channels into my PBNs. Again, only 20 hours on the 750s.

I'll get the Spectrons on Tuesday, and hope to compare by Thursday.Unfortunately out of town Tuesday night and Wednesday.

Talk to you then.
Lubes3

Hello Perrew,

The preamp was Joule-Electra LA-150 Signature and front end Marantz SACD Player ( I can't recall the model number).

Lubes 3: I think I use word "glassy" as oppose to silky smooth, liquidity etc. But again, I did not audition the DNA-750 - they could be different.

All The Best
Rafael

Dob, you might want to try it before you write off tubes with the WPs. There was a resonant peak that you referred to in the Watts at 2KHz, so Wilson installed a trap that set the impedance to 2 ohms or less. What do many transistor amps do with low impedances? They make more power as we all know. This exacerbates the resonance issue. Now put a tube amp on there and what do you get? The power goes down, and the tweeter resonance is controlled.

For some reason, the low impedance in the woofer range of the Sasha does not seem to bother our MA-1. It might be due to the phase angle, but in the system I heard you could play it to a very nice volume and yet the VU meters on the amps hardly move.

"Dob, you might want to try it before you write off tubes with the WPs "

Hello AthmaShere: Both amplifiers I mentioned in regard to the sound of W/P were tube amplifiers: AEC Classic 60 (60 wpcs) and Equilibre (225 wpc)

I did so call "soprano experiments" to test amplifiers when I decided to change my old ARC 60: In other words when soprano coming to crescendo then all but Equilibre amplifiers (and I tested almost every tube amp under the sun) recreated her gorgeous voice as police siren - so many distortions was there at 2 kHz. Only Equilibre could show this voice(s) equally gorgeous at low and high levels and I grabbed it!!!!

" ....you could play it to a very nice volume and yet the VU meters on the amps hardly move "

As I am sure you are well aware, NAD experiments showed that human ear/brain is sensitive to musical peaks of even 3 msec duration and unless its heavy metal it will rarely be longer then 500 msec (may be less then 0.1% of recorded music). That means that while your ear/brain will register the peak (distorted or not)- your VU meter will barely move and I doubt if you could see its movement over just a few hundred milliseconds duration.

When I read your post I checked McCormack and Spectron specs - since the author of this thread is interested in these two amplifiers.

Most interesting is that at full output McCormack distortion level is 1% and Spectrons is 0.3% or 30 time better.

So, if he - in his testing - will stress his system with Mahler symphonies then.... I am waiting for his report !!!!

All The Best
Rafael

Hey guys. Just hooked the Spectron Musician III Mk2 Mono-blocks up for about 4 hours, so only initial observations. Contrary to what I thought I would hear, I prefered the highs on the Spectrons, cymbals/brushes sounded much more real. The McCormacks almost seemed rolled off but not as natural. Now the bass was just the opposite. They both played deep and powerful, but the bass of the McCormack had a more natural, woody, organic sound. Overall the Spectros seem to have higher resolution and the McCormacks seem more forgiving, maybe due to lower resolution.

Dob, I really don't look too much at specs to judge a piece of gear's sonics, but your quoted distortion figures could account for some of what I heard.

At this point I need to buy or return the McCormacks (they have about 75 hours now), but I'm not ready to make a decision yet, so I will return the McCormacks. I'm not counting them out, as I found them very musically engaging.

I have the Spectrons for 2 weeks, so I need to put some hours on them to form a better opinion of their sonics.

Till then--
Lubes3