Spectron musician VS. Pass Labs Amp

@Genkides, you should try the PASS amp then. XA-30.5 can grip the woofers of Focal 1037BE speakers like no other. I did have lean bass syndrome with earlier X series. XA-.5 series in a completely different league. I haven't heard Spectron amps however.

I also ended up with a Joule-Electra preamp and Spectron monoblock amps. Best sound in my system of what I have tried. Pass amps were on my short list to try until I figured out how much heat they give off. I live in Texas and heat is a real issue. In August when I had my tube monoblocks I did not play them. My AC could not keep my house cool with the tube amps running.

Hello Audioconnection,

In principle, you are correct: tube preamp have relatively high output impedances and most ss amps have relatively low input impedances and matching such would result , again in principle, in some losses at top and bottom

Now to specific componenents in question: I believe that output impedance of BAT VK51SE is (much?)less then 1000 Ohms (VK does not like tube buffer). In such a case the ratio of input/output impedances would be at least 15:1 which is more then sufficient for good match as it would cut bandwidth by 5-6 percent only. Moreover, I presume PASS amp is wide bandwidth amplifier and then it would be simply inaudible.

I own Spectron, another ss amp, and I have tried many tube preamps with it including fantastic Rex by BAT. Today, I have Joule-Electra LA-300ME and its the match made in heaven.... WE can and may be should match the best tube preamps with best ss amps, I firmly believe

All The Best

Because when you wrote
(( My preamps are BAT 51SE and NAT Audio Symmetrical, both are tube pre))
loading down a tube pre is going to hurt your perception to everything not only bass.
Cheers Johnnyr

Audioconnection,
How do you know that my Pass X350.5 and X600.5 bass response were sluggish bass causing non desirable outcome ?

(((My preamps are BAT 51SE and NAT Audio Symmetrical, both are tube pre,)))
((I know that my Spectrons are extremely superior to any other amps I have owned playing my speakers.))
All you proved is that you loaded down your tube preamps
into a 15K input imp causing them to play sluggish bass into the Pass further causing a distorted non desirable outcome
kind of like shooting the messenger.
Cheers Johnnyr

Terryakhan, interesting experience with Spectron and Focal speakers. My experience was different. Really tried to like the Spectron with my Focal 1027be speakers and it just didnt click. Even the dealer was mystified and blamed the speakers as having a loose and woolly bass. There was just no synergy with my system (pre's used were a Cary SLP03 and a Herron). I moved on with some regrets (I passed up a good deal on the Spectron).

"Did anyone compare?
What was the pre you used with each?
....And what is your impression?"

Yes, I am one of the people who have compared and owned the X350.5 and a pair of X600.5 compared to my MKIII MII.
I kept the Spectrons.
My preamps are BAT 51SE and NAT Audio Symmetrical, both are tube pre, speakers are Analysis Audio Amphitryons, Magnepan 20.1 and coned JM Labs Utopia Novas.

Both X350.5 and X600.5 played my Novas perfectly well without the lack of anything, however, playing the large planars, I was not not satisfied at all with the bass response so I moved up to the X600.5 which generated bit of improvement but not close enough to what I am looking for. This struggle went on for over a year.

The Spectron played my Novas effortlessly as if the speakers did not exist.
In the case with both planars, it is music like never heard before, with the bass I am looking for after 25 years.

I know that my Spectrons are extremely superior to any other amps I have owned playing my speakers.

Spectrons presentation brings me to the closest degree of a live music performance playing both coned and unconed speakers.

Hello Audiofeil: Its Pass XA-200.5 - I committed typo error. Sorry. Still, excellent amp, still expensive tooooo...

I'm not familiar with the Pass XA-300.5.

Hello,

Do a search: there was a plenty of comparison. Both are very good manufacturers. However, note that Pass Labs amp, XA300.5, that truly match Spectron Musician III Mk2 is substantially more expensive. Surely you will not regret listening with either one

All The Best
Rafael