are you listening in Triode mode or Tetrode mode? Have you tried both modes?
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The ones I heard (the 350 watt model at the time) struck me as powerful and a tad grainy. But,to be fair, the grain was in comparison to the mega-buck Levinson system in the other room. What I do remember is that my head was picking out the flaws but my feet were tapping to the music.
Everything put throught the VTL had this effect; I would mentally note the not-quite-perfect hf response, the slight grain perhaps, and so on. And my body would tell me it didn't give a damn...to stop thinking and just enjoy the freakin' music!
Frank Sinatra was illustrative of this; within seconds my fingers are snapping and my other hand is reaching for a whisky.
If the driver tubes affect the sound of the 450 as much as the 750, I would suggest swapping the original Sovtek tubes for something with less distortion and wider bandwidth.
I have not completed my testing, but Brimar and Sylvania Military grade in 12AT7 are excellent. Also, high frequency response was increased, soundstage brought in focus and distortion decreased by replacing the supplied power cord with Purist Dominus. I suspect Elrod, Nordost and Purist would all be excellent choices for this amp, but have not tried them all.
Let us know how it works out if you experiment.
Thanks for everyone's opinion. Mejames! I have tried two modes Triode and Tetrode but my favor is Triode's sound with more musical and dynamic. How is your experience? It should be much better with MB750, isn't it?
Albertporter! I have only tried the Elrod EPS3 Signature and they are the same. I guess the reason is the source (Audiomeca Mephisto IIX is too laid back?)
Sorry, I have not heard the Audiomeca Mephisto so I cannot know if that is the issue.
I assume youve tried various feet under the Audiomeca, such as the Symposium Roller blocks? The source end of the system, particularly the CD player and preamp have a great deal of affect on what comes out of the amp.
As for power cords, the Purist is more detailed than the Elrod and less compressed. The price for a pair of input tubes and a set of Roller Blocks is less than the Elrod or Purist. I would consider the less expensive auditions, working my way up as necessary to reach your goal.
I have found, with my MB-185's, that Albert is correct about upgrading the input tubes (NOS 60's Sylvania goldpins recommended by Upscale were better than anything of more recent vintage I had lying around the house). For power cords, I don't play in the same range that he does, but have found that a base model Shunyata cord substantially raises the get up and go factor vs. the stock cord or the other alternatives I've got, and it's possible their top amplifier cords would work even better.
Also, there's the issue of the coupling-capacitor upgrade to the InfiniCaps VTL uses for their Reference series, an available factory option that's said to sound more highly resovled yet more refined as well.
But all this aside, my experience definitely indicates that tetrode mode will yield the best extension, driver control, dynamic impact, spatial delineation, and transparency/resolution these amps are capable of, although at a slight cost in terms of natural tonal balance (a bit leaner below, a bit brighter above) and ultimate harmonic purity vs. the triode mode. So while you might prefer triode for intimate vocals, I'd try tetrode again for larger-scale stuff.
Nguyenchiro I actually owned the 450 signature previous to the 750's yes they are quite a bit better overall. The upper bass is much better much more authoritative and the resolution of detail is improved upon also the dynamics are improved too. I previously used a Audio Aero Capitol Mark 2 CD player have upgraded this with the Wadia combination, neither of these sounded what I would call too laid back. your system shows the Bybee line conditioner are your amps plugged into it? Have you tried the system without the conditioner? If amps are plugged into it try plugging them directly into the outlet. Also is your electrical circuit just on one circuit breaker? Amperage its rated for? What's your cabling currently? current preamp is? Wondering if it's the Cary? They have a reputation for being very laid back. oh are you running with the RCA input or balanced? The balanced sounds a little less laid back.
Just to comment on Mejames' last suggestion, this hasn't proven to be the case in my set-up. From my fully-balanced Levinson 380S preamp, and using identical interconnect models in both XLR and RCA versions (from two different brands, for a total of four varieties tested), I found the single-ended connections as a class to sound a bit more direct and present. This is just as Luke Manley told me to expect for his non-balanced amp designs, as single-ended input presumably eliminates a little extra in the way of unecessary signal path length and solder connections. (For the record, I have generally found balanced connection to be superior between balanced components.) I wonder if Mejames was comparing otherwise identical cables?
hello yes was comparing the XLO SIGNATURE 2 RCA version and the balanced signature 2 IC's seemed like everything moved forward about 1 foot in the soundstage. It could have changed because of the truly balanced Wadia equipment or because of the amplifier I really can't say why but balanced definitely sounded much better overall in my system. I understand the 750 reference is a truly balanced design [which may explain why it sounded better for me vs.Zaikesmans not truly balanced mb 185 not sounding better via balanced cables] don't know if the 450 is truly balanced or not.
I am currently using a pair of MB 750's and they are great. I think I may be done buying amps. I love these things, and at $8000.00 a pair used, I have 800 tube watts and they are cosmetically beautiful also. The same wattage would cost you almost twice as much with ARC. I am not a whealthy man, so to me I call that the point of diminishing return.
VTL customer service is also wonderful, I called them after business hours a few weeks back and Bea Lam called me back on her cell phone from CES in Vegas and calmed me down when I thought my amps were making noise, and she helped me find out that it was a bad tube in my Hovland HP-100. Hope this helps!