That would be about a year for my friend who is retired and listens 8 hrs/day
And he just got the latest (?) VTL 450 monoblocks and 7.5 preamp.Vtl 750
- Thread starter Albertporter
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That would be about a year for my friend who is retired and listens 8 hrs/day
And he just got the latest (?) VTL 450 monoblocks and 7.5 preamp.That would be about a year for my friend who is retired and listens 8 hrs/day
Or, put it this way - about 25 cents an hour. A bargain - if you have a top Koestu cartridge the cost per hour of music is almost ten times this value.
micro,
This is not the consensus opinion. My Siegfried's, as much as I love them, burn output tubes at a considerably faster pace. I would say 1500 hours is about it for KT88s and I've tried both Shuguangs (KT88-98) as well as Gold Lions. Others have commented similarly and a few believe that output tube life is even less (1000 hours). When I had ARC Ref 300 Mk II's, I used to get 2000-2500 hours of use. What is confusing is that Luke believes his amps should yield longer output tube life because they are biased at less current that the ARCs (I may have this wrong but 45ma for VTL vs 60ma for ARC) although the VTL biases at a higher voltage. It just may be a situation of having your "mileage" vary depending on how hard one drives their amps. Admittedly, I play at symphonic levels regularly but I just don't like the 1500 hour output tube life scenario. However I cannot bring myself to go with any other powerful tube amp since for me, reliability is key. Once you've blown up a few ARC amps and sent them back to Minneapolis, its hard to give up the masterful VTL protection circuitry. Blown tube? No problem. Change the tube and be up and running again in about 30 seconds! Ah, life is compromise. I'll live with the 1500 hour tube life in return for an otherwise spectacular amp (which, in triode mode, is simply ethereal if you don't need bass slam). I'm in Albert's camp. 1500 hours. That's about it.
Marty
This is not the consensus opinion. My Siegfried's, as much as I love them, burn output tubes at a considerably faster pace. I would say 1500 hours is about it for KT88s and I've tried both Shuguangs (KT88-98) as well as Gold Lions. Others have commented similarly and a few believe that output tube life is even less (1000 hours). When I had ARC Ref 300 Mk II's, I used to get 2000-2500 hours of use. What is confusing is that Luke believes his amps should yield longer output tube life because they are biased at less current that the ARCs (I may have this wrong but 45ma for VTL vs 60ma for ARC) although the VTL biases at a higher voltage. It just may be a situation of having your "mileage" vary depending on how hard one drives their amps. Admittedly, I play at symphonic levels regularly but I just don't like the 1500 hour output tube life scenario. However I cannot bring myself to go with any other powerful tube amp since for me, reliability is key. Once you've blown up a few ARC amps and sent them back to Minneapolis, its hard to give up the masterful VTL protection circuitry. Blown tube? No problem. Change the tube and be up and running again in about 30 seconds! Ah, life is compromise. I'll live with the 1500 hour tube life in return for an otherwise spectacular amp (which, in triode mode, is simply ethereal if you don't need bass slam). I'm in Albert's camp. 1500 hours. That's about it.
Marty
Hi Marty,
So how do you find the sonic signatures of the VTL to differ from ARC? I have heard people say that ARC sound more "solid state". However, with my regular Svetlana tubes, the VTL sounds SS also (in a good way - not overly lush).
Thanks
Marty - surely, I was only referring my experience.
Just look at power requirements for the MB750 - 430w iddle, 1300W peak full power. This means that cathode current of the power tubes can go from 30 mA (maximum idle current recommended by VTL) to 140ma at peak power. Considering that the VTLs are class AB, cathode current is almost proportional to power. As tube life is mostly dominated by cathode life, that is given in Ampere x hour (there are some other dependencies that I will ignore) we can have a large variance in tube life depending on the average power the amplifier is delivering.
My speakers are Soundlab, that have a high impedance in most of of the audio spectrum, and do not need high current, although they are not very sensitive. But most modern speakers have low average impedance and need a lot of current - I tried to find some information about the Pipedream impedance, but had no success. Also, my room is medium size - only 40 square meters. If you listen loud in a large room, tube life will be much shorter!
Hope they've improved over the years. Hope Penta KT88s are better than their 6550s. Tried them years ago and they sounded like crap: bright and no bass in cj amp. And they didn't last worth a damn.
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Thanks. I wonder if the tubes maintain their sonic signature across brands or if there is synergy with the particular amp. I have heard that the Pentas are the way to go instead of the 6550. I do like having nice bass, though...
And you remember well. Fifteen years ago, the Chinese 6550 tubes were a disaster - they went into short circuit easily, exploding the cathode resistor. Also, grid current was very high, making bias very unstable. Although I believe these are problems of the past and recent tubes are reliable, just looking at this tube brand still evokes in me the smell of burnt resistors ...
With VTLs I always used the Svetlana 6550c , including the SED type.
A good friend uses Sovtek without problems.
But since my days with an ARC D70 - my first serious tube amplifier - using GE 6550s, many 6550s went through my system. I remember several cj's also using GEs, ARCs classic 60 and 120 (those were the victimes of the Chinese tubes, later replaced with Sovteks), VAC P80/80 with Electroharmonix, Jadis DA30 and Defi7 (not sure anymore of what brand they used). A short experience with JJ 6550 tubes was a disaster.
Nowadays I always burn-in new 6550 tubes for 50 hours in a cheap amplifier before putting them in service.
I don't know if anyone else noticed, the SED 6550 Wing C tube has been back-ordered most of this past year and to make matters worse, the limited stock that is now available has increased 30%. Unfortunately the old price is not being honored, even for those of us that have been waiting.
Because of this I ordered reissue Gold Lion KT88 which I never thought I would do. I hope to try these in my VTL 750 soon and see what results.
Yes, that tube has not been available since late summer/ early fall, as far as I know. Please keep us posted on the KT 88.
I replaced my SED 6550s (which are the current best production 6550 IMO) with the GL reissue KT-88s in my Jadis Defy 7 MKII. They are a good sounding tube and they were recommended to me by the owner of Jadis. I really don't think they sound any better than the SED 6550s. As I'm sure everyone is aware, Svetlana lost the right to use their name on their tubes because New Sensor bought the rights to the name. If you buy *Svetlana* branded tubes, you are really buying Sovtek tubes that say Svetlana. If you want real Svetlana tubes, you have to buy SED branded tubes. Apparently there have been production issues with the SED 6550. I have no idea what the story is.
I was told by the importer that SED (St. Petersburg) moved their production equipment or location, that part was not clear. I am well aware of the Svetlana / SED name debacle and have posted on that topic for several years.
I don’t know if the reason given contributed to the lack of tubes all those months but it sure dd not help to wait and then face such a steep price increase.
In a discussion by phone with VTL I was told that both the SED and Gold Lion where acceptable choices. I'll post comments about any performance differences when I do the test.
Anyone else who's compared these tubes in VTL or other high quality amps, your comments would be welcome and appreciated.
Agree! I grew up listening to this album (LP) before the Wall, DSOTM and all the rest. I just got the remastered CD and enjoy it a lot.
SED 6550 Wing C tube is defintely the way to go.
Ken Stevens tried the new Audio Reserach tubes in his Statement Amps at CES and everyone was happy when we went back to the 6550s
Donald Saltzman of Absolute Sound also swears by the 750s to drive his MG21.1. Only tube amp powerful enough to make the Maggies sound effortless.
I personally feel the amp use a very simple circuit and very simple execution, which is also good.
My only criticism of the amps is that the manufacturer does not have the Zen like dedication to using the best sounding parts at every location.
Thus, I think the amp could be greatly improved in terms of openess, extension and transparency.
On the other hand, someone tweaking it could more likely ruin it.
But I am just saying there is a lot of room to make them sound better.
Use hexfreds in the power supply. Bpyass the large filter caps with 10uf poly caps. This just makes the bass sound more acoustic. .1uf bypass caps is bullshit. The elecrlytics are slow so you needed a faster cap to speed up the supply. There is so much more that sould be done here. But still a very good amp with few faults. All errors are errors of omission
Ken Stevens tried the new Audio Reserach tubes in his Statement Amps at CES and everyone was happy when we went back to the 6550s
Donald Saltzman of Absolute Sound also swears by the 750s to drive his MG21.1. Only tube amp powerful enough to make the Maggies sound effortless.
I personally feel the amp use a very simple circuit and very simple execution, which is also good.
My only criticism of the amps is that the manufacturer does not have the Zen like dedication to using the best sounding parts at every location.
Thus, I think the amp could be greatly improved in terms of openess, extension and transparency.
On the other hand, someone tweaking it could more likely ruin it.
But I am just saying there is a lot of room to make them sound better.
Use hexfreds in the power supply. Bpyass the large filter caps with 10uf poly caps. This just makes the bass sound more acoustic. .1uf bypass caps is bullshit. The elecrlytics are slow so you needed a faster cap to speed up the supply. There is so much more that sould be done here. But still a very good amp with few faults. All errors are errors of omission
I've known Saltzman for many years, he's a great guy and loves to listen loud :^).
In fact, two of my four VTL 750 amps came out of his system, but that was a number of years ago.
I have several things going on that prevent me from immediately testing the new GL tubes but your comment about the Wing C mirror my own experience.
As for your comments about VTL and the parts they use. I have no idea what a parts swap would do but sometimes these modifications backfire. The customer has great expectations and after investing significant time and money they wind up with a trade off, or worse.
The VTL 750 is an established, reliable, powerful and attractive amplifier with a sonic signature that's easy to like. For more performance the VTL Siegfried is supposed to be an even better choice. I've not listened in my own system but it's a more evolved circuit and claimed to be superior performance.
I'm using Winged SED 6550 C's in my ARC D70Mk2 and I like them almost as much as the original GE 6550's. The GE's are a tad more expressive, but they are very hard to source today and fairly pricey when you do.
Haven't heard the new ARC tubes, but I would be surprised if they were a lot better than the SED's.
. The GE's are a tad more expressive, but they are very hard to source today and fairly pricey when you do. Haven't heard the new ARC tubes, but I would be surprised if they were a lot better than the SED's.
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