Vtl 750

[microstrip]

Of course, Microstrip, you are running a similar combo, and I imagine you have no affiliation with either ARC or VTL.

And you imagine well - my only affiliation in my taste and my budget. I am a good friend of many local distributors, but most of the time I buy second hand if I can find what I want.

I have listened to the ARC Ref610T and they are superb amplifiers, without doubt it is better than my VTLs, but would cost me four times the price I paid for the MB750s and have 40 6650c tubes that are operated at high bias, needing replacement every 1500 hours and generating a lot of heat.

As far as I know, the main issue of the REF610T is tube quality - tubes must be accurately matched in groups. You must use pre-aged selected tubes to get reliable operation. With the VTLs you can control bias individually.

 

[Albertporter]

And you imagine well - my only affiliation in my taste and my budget. I am a good friend of many local distributors, but most of the time I buy second hand if I can find what I want.

I have listened to the ARC Ref610T and they are superb amplifiers, without doubt it is better than my VTLs, but would cost me four times the price I paid for the MB750s and have 40 6650c tubes that are operated at high bias, needing replacement every 1500 hours and generating a lot of heat.

As far as I know, the main issue of the REF610T is tube quality - tubes must be accurately matched in groups. You must use pre-aged selected tubes to get reliable operation. With the VTLs you can control bias individually.

I have not heard the 610 in direct comparison to the VTL 750 but the Wilson distributor in another country (that I'm friends with) says he made the comparison and prefers the VTL. He recently dropped the ARC line after several consecutive failures, he decided to stop promoting it due to the high cost of repair and problems with the factory providing warranty service.

 

[MylesBAstor]

I have not heard the 610 in direct comparison to the VTL 750 but the Wilson distributor in another country (that I'm friends with) says he made the comparison and prefers the VTL. He recently dropped the ARC line after several consecutive failures, he decided to stop promoting it due to the high cost of repair and problems with the factory providing warranty service.

My friend's probably going to plunk down the greenbacks for VTL 450 amplifiers this week and if lucky should have them in a week (then comes the break in). Should be interesting as I've been hounding him to get rid of his ss amplifier. They'll be used with Totem Forests speakers (of which we discovered after complaining about something lacking in his system, including the bass, that one of the bass drivers was dead; now have to figure out if it's the speaker or the xover ).

 

[Albertporter]

My friend's probably going to plunk down the greenbacks for VTL 450 amplifiers this week and if lucky should have them in a week (then comes the break in). Should be interesting as I've been hounding him to get rid of his ss amplifier. They'll be used with Totem Forests speakers (of which we discovered after complaining about something lacking in his system, including the bass, that one of the bass drivers was dead; now have to figure out if it's the speaker or the xover ).

Myles, does your friend plan on purchasing the new VTL design or the older 450?

 

[MylesBAstor]

Myles, does your friend plan on purchasing the new VTL design or the older 450?

I assume the new one.

 

[caesar]

Albert,

So how do the sonic signatures of Atmasphere and VTL 750 compare driving the Soundlabs? Thanks

 

[Albertporter]

Albert,

So how do the sonic signatures of Atma-Sphere and VTL 750 compare driving the Sound-Lab? Thanks

Caesar,

Remember I had the old Sound Lab Ultimate, the one with high impedance in the bass and low impedance in the highs and not very efficient. The new Sound lab XP would probably result in a different outcome in listening tests.

During the time I had the Sound Lab I tried many amps, Viva SET, Air Tight Mono, modified Altec, VTL 750, Atma-Sphere MA2, Atma-Sphere MA240, Atma-Sphere M-60, Tube Research GT-400 and even some modified Dynaco mono blocks. The best sounding were the Viva, Atma-Sphere MA2, VTL 750 and Tube Research GT-400. I'm not sure, but the Tube Research may have been the best sound I ever had with my Sound-Lab but for some reason (load?) the Tube Research never ran more than a few weeks before a catastrophic failure which required soldering and tube replacement to get back in business.

Obviously this soured me on the Tube Research even though it sounded wonderful. The Viva was absolutely beautiful in the midrange but had no contrast or dynamics nor the ability to play anywhere near live levels. Not the Viva's fault, it's very low power and not ideal for difficult load like Sound-Lab. So basically the winners were Atma-Sphere MA2 and VTL 750, with the VTL having superior bass, superior dynamics and superior sound pressure level. The Atma-Sphere won on transparency but that alone was not enough to sway my decision.

I must state here, the Atma-Sphere I owned was a VERY old model. Ralph has implemented at least three major upgrades since I owned mine, so taking my word as gospel against the newest versions would be a mistake.

 

[caesar]

Thank You!

 

[Jacob E. Heilbrunn]

Many thanks to Albert for the plug above, which I just saw, but I think I should shed the thin veil of anonymity kindly draped over me to reiterate, as per my original review, that the Siegfried is, in my view, superior to the 750--more punch, more delineated, more secure soundstaging, more power. I found that the 750 did not have the power to grab the bottom octave of my Magnepan bass panel. I ended up selling two pair of 750s (one pair went to AP) as well as the Wotans. Don't get me wrong: I enjoyed my time with the 750s and I'm sure they sound excellent on a more efficient speaker. They came closest to matching the Siegfried when run with KT-88 tubes, which lowered perceived distortion, but the Siegfried still sounded cleaner, even with 6550s. Ultimately, they (the 750s) weren't for me.

With the Wotans it becomes more of a headscratcher. If you have the cojones to deal with the 24 output tubes per side, then you'll get seemingly unlimited crunch and majestic sweep. But I still think the Siegfried has lower distortion, lower noise floor, more nuance and speed, because of all the regulation, than the Wotan.

Perhaps a new super-Wotan looms on the horizon? A new firebreathing dragon of an amplifier that might be called mighty Fafner? For now, Siegfried looms large.

 

[caesar]

Many thanks to Albert for the plug above, which I just saw, but I think I should shed the thin veil of anonymity kindly draped over me to reiterate, as per my original review, that the Siegfried is, in my view, superior to the 750--more punch, more delineated, more secure soundstaging, more power. I found that the 750 did not have the power to grab the bottom octave of my Magnepan bass panel. I ended up selling two pair of 750s (one pair went to AP) as well as the Wotans. Don't get me wrong: I enjoyed my time with the 750s and I'm sure they sound excellent on a more efficient speaker. They came closest to matching the Siegfried when run with KT-88 tubes, which lowered perceived distortion, but the Siegfried still sounded cleaner, even with 6550s. Ultimately, they (the 750s) weren't for me.

With the Wotans it becomes more of a headscratcher. If you have the cojones to deal with the 24 output tubes per side, then you'll get seemingly unlimited crunch and majestic sweep. But I still think the Siegfried has lower distortion, lower noise floor, more nuance and speed, because of all the regulation, than the Wotan.

Perhaps a new super-Wotan looms on the horizon? A new firebreathing dragon of an amplifier that might be called mighty Fafner? For now, Siegfried looms large.

Jacob,

How do the sonic signatures of the big VTLs compare to the big ARC amps? Would one type of listener favor one brand over another, or can one live with either ARC or VTL at that level of performance?

Also, how good is the bass produced by the monster VTL compared to a quality SS amp?

Thanks!

 

[microstrip]

Also, how good is the bass produced by the monster VTL compared to a quality SS amp?

Thanks!

I could compare the Krell FPB750Mcx driven by a Krell KPS25S with the VTL MB750s driven by a Ref3 in my Soundlab A1 Px for some weeks. The bass from the Krells was more defined, had greater control and punch - percussion sounds were fast and incisive. The sound was more dramatic. But the VTLs sounded more powerful and although less defined their bass energized room in a way that seemed more real - you could feel a kettledrum in the space of the auditorium, not only the instrument detail. Paniagua Lafolia recording seemed much more played in a stage with the VTLs than with the Krells in the A1 px.

 

[caesar]

I could compare the Krell FPB750Mcx driven by a Krell KPS25S with the VTL MB750s driven by a Ref3 in my Soundlab A1 Px for some weeks. The bass from the Krells was more defined, had greater control and punch - percussion sounds were fast and incisive. The sound was more dramatic. But the VTLs sounded more powerful and although less defined their bass energized room in a way that seemed more real - you could feel a kettledrum in the space of the auditorium, not only the instrument detail. Paniagua Lafolia recording seemed much more played in a stage with the VTLs than with the Krells in the A1 px.

Thanks, Microstrip. Sounds like the "more accurate" vs. "more real" dilemma.

If you owned the Krells, would you be tempted to plug them in once in a while, or would you keep the VTLs in your system most of the time?

 

[Jacob E. Heilbrunn]

Vtl

The Wotan will go down low as will the Siegfried for that final bass octave. I don't have enough experience with ARC to compare.

 

[MylesBAstor]

The Wotan will go down low as will the Siegfried for that final bass octave. I don't have enough experience with ARC to compare.

Jacob:

Good to see you here! Albert and I were just talking about you the other night

 

[Steve Williams]

Jacob likes it here so much that he registered under two names but whatever it takes to get him here

 

[microstrip]

Thanks, Microstrip. Sounds like the "more accurate" vs. "more real" dilemma.

If you owned the Krells, would you be tempted to plug them in once in a while, or would you keep the VTLs in your system most of the time?

A few recordings with strong bass content, such as Patricia Barber Modern Cool and a few tracks of the Burmester test III sampler sounded better with the Krells. And the Krells were much better to impress friends. But as soon as they left I returned to the VTLs.

 

[caesar]

Holy Smokes!!!!!!!!!!!!!! I can't believe how good this amp is driving the Soundlabs!

 

[caesar]

Thank you Albert!!!!!!!!!!!!!!!!!!!!!!!!

 

[microstrip]

Sam,
I change output tubes at around 1500 - 2000 hours but VTL and SED say they are rated for more.
I prefer keeping tube performance more linear and swapping more frequently.

Although it depends on tube quality, VTL are more friendly in tube life. I quote the VTL750 v2.2 manual:

"Tube replacement need not be considered until after approximately 3000 hours of use (roughly 3 to 4 years depending on your listening requirements.) As the tubes age beyond their peak performance they begin to lose their ability to provide full power. This usually results in some loss of control in the bass and a general softening of the sound in the upper frequencies."

I had some 6550C SED tubes used in a pair of VTL MB450's approaching 4000 hours and they still tested perfectly in a transconductance dynamic meter.

 

[c1ferrari]

..and that's why God gave us the p-n junction!

Haha...I read this and thought "Petticoat Junction"!