Hello, I really like Rogue products. My suggestion would be to call Rogue and ask for Nick or Mark who is the owner. They really helped me out when I demoed the 180 darks and I needed to bias them since they probably don’t leave the store a lot due to their size and cost. Also, FYI. Do not use ceramic fuses. They do not recommend them for the tube fuses. I also denied the RP7 preamp. Very nice also fully balanced like the 180 darks. This is the store in the Chicagoland area where I get some of my gear. https://holmaudio.com/Very nice guys. |
The Telefunken 12AX7 is really superb as the front end input tube. It lights up very brightly when it is powered on and scares the heck out of you; but it sounds amazing. |
Thanks everyone for their feedback.
Regarding the above comments, I suspect that their concern about the VK-3i actually came from my experience. That happened nearly 10 years ago and so I assume that Upscale Audio has updated their information regarding the BAT preamp because of my tube losses. I think I have those EH tubes in my preamp now - so it's interesting to note that AFTER I had issues they issue advice to avoid my pain.
That said, it also looks like, based on the Audioshark forum, that another user of the VK-3i has also discovered that it is a bit more sensitive with tubes than other preamps.
So, must consider what to do here. I did like the sound of the National 7DJ8s and the Philips 7DJ8s before they were ruined - a little mellower on the top -- but I would also not be happy to find out that my VK-3i destroya $500 worth of NOS 6922s... |
@jji666 Read the 2nd paragraph about Upscale and 7DJ8s in the Vk-3i preamp. Seems like staffers there might not be on the same level as uncle Kevvy. https://www.audioshark.org/balanced-audio-technology-bat-38/tube-noob-seeking-education-11051.html#p...Agree with others, give Brent Jesse a call, and see what he might have in stock. Start with preamp tubes first, for sure. Then, after they are broken in, try input tubes in the amp next. Another tip, I have multiple pairs of super matched curve-tracer balance tested tubes from Brent for my amps. While they have a deeper sound stage in some cases, I've been having some luck with the latest PSVANE MKII or Art Series 12Au7, and same with friends using the 12Ax7s from PSVANE fwiw. A little more midrange/forward with them but they sound nice for new production tubes. Best of luck. |
As one of the prior poster mentioned the amp is voiced different than the "OLD" tube or valve amps. Where an older valve amp may sound "Bright" or have harsh mids, a newer design takes advantage of that valves characteristics.
NOS is kind of a spoof if you don't know what your looking for. They can cost a lot of money and offer ZERO.
Signal valves are a good investment net the money you spend.. DON'T get sold a bunch of high priced NOS. New reproduction are probably a better overall sound..
An older amp I might spend the money, Mac, Marantz, Fisher, HH Scott, after a rebuild. BUT newer gear, Usually require a very quiet valve more than anything else.
Newer voicing doesn't count near as much as they use too on the actual quality of the valve "SOUND", just NO microphonic.
No matter the amp. A great RCA or Tellie black plate signal valve goes a LONG ways... I don't care who made the amp.. :-)
Regards |
Rogue categorically recommends Mullard small tubes as an upgrade for their gear . My experience with Mullard tubes in this application tended to make my sound veiled as if a blanket was thrown over my system . I’ve tried nos Mullard , Seimens Ecc, Seimens silver plates Phillips SQ , and Telefunkens, including standard , Tektronix, and Black Coated . I’ve also tried most of the better domestic nos driver tubes as well . Based on my experience, I highly recommend Telefunkens. Now in that regard , nos Tesla and Tungsram are closer to the Telefunken sound at a lesser price . Verify with Rogue , but generally in a 3 tube circuit , you have a phase splitter and a gain application. In most cases the single tube will have a greater effect on SQ change when rolling . In the 6992 application my favorite tube is the gold pin Telefunken E88CC, the gold pin Tesla is a close second . This I prefer over the Seimens CCa or the Phillips SQ. Rogue uses a SS rectifier , which eliminates rolling rectifier tubes. Although I have nos power tubes like the GEC and Tung- Sols, I’m happy with new production tubes like Gold Lion and TUNG-Sol . However I really like the out of production SED Winged C power tubes .NOS Mullard rectifier and power tubes are very good and highly prized . So to be brief , try nos Telefunkens in both , but check and see if you can suffice with a single tube in the 120’s. Regards, Mike B. |
Siemens Halske E88CC and Cca $499 each.
I don't think you need the best of the best for your first tube roll.
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I agree to start by installing NOS tubes in the preamp. I don't know the layout of the BAT but the gain stage is most noticeable to tube rolling.
BTW, don't be concerned about using NOS power tubes. There are decent power tubes being made today, can't say the same about small signal tubes.
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The signal is much smaller/more delicate at the preamp. So it follows that any change will have a greater impact there rather than the amp. |
Thank you. This is helpful advice.
Upscale didn’t know. I don’t think they should be quite so certain in their marketing materials that 7DJ8s work anywhere. But I couldn’t say that there was anything specifically said to me, or omitted, that was a problem with Upscale. I ordered several sets and had ruined most before Kevin could respond. The tubes DID sound good...
The issue was years ago, and so I’m not going to pursue it with them now. It comes up mainly because at that time I decided not to try NOS tubes in this preamp again. But now that I have it available to my best amp/speaker combo again, I am again wondering if some NOS would add magic. |
See if you can get Viktor to talk to Upscale or get an email from him stating the 7DJ8 is not suitable for his preamp and pursue the matter with Upscale. Did Upscale know that you planned to use the tubes in a BAT pre?
Some manufacturers advise that you can't do better than the stock tubes because that's what they designed the pre or amp with, others encourage tube rolling. I guess unless you hear from someone who has the same components and had success tube rolling, I'd follow the manufacturer's recommendations. |
Thanks again. Yes I did tell Upscale about the issue. They tested all the tubes and sent the survivors back to me, but I haven’t used them as the only 6922 sockets I have are in the BAT. I can’t put them back in there.
The only gripe I have about Upscale was his statement about 7DJ8s being a perfect substitute ...”trust Uncle Kevie on this one.” Not “make sure this is ok with your gear.”
Oddly, Victor at BAT seemed skeptical that changing tubes would have much impact.
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I’m not familiar with your components, but you want to first upgrade the input tubes or voltage gain tubes, same thing, I think. As to whether the preamp or amp would have the most impact, I’d guess the preamp unless the tubes in your pre are not used for voltage gain and are in the amp.
That’s unfortunate about the 7DJ8s, but it shows why you need to talk to the manufacturer. 7DJ8s are often used as subs for 6922s these days. Did you talk to Upscale about the problem?
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Better 6922 for the preamp, but remember that the manufacturer designed your unit with modern sounding tubes in mind so you want something better in that direction meaning linear sounding tubes.
Believing that your pre has Sovteks or EH I would go with Siemens Halske E88CC and Cca up to 1967 production, for a classic tube tone, or their bigger brother E188CC same period, for more bass and treble. But definitely i would try to find some Voskhods 6N23p 74-79 production for their better flow and the info retrieval at a much lower cost.
Of course you can try anything from that family and you can get better results from the ones you already have as long your pre does not push them too much in which case your choices are limited.
A good move is the check with BAT if that is the case before spending your cash.
For the power amp I would check to put the best I could afford in the cathode follower position leaving everything else as is.
A new world.
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Thanks! I’ve dealt with Kevin at Upscale. They sold me a bunch of 7DJ8s that they promised were fine substitutes for 6922s but my BAT destroyed them, and Victor at BAT said he had no idea why someone would represent 7DJ8s as suitable. I know the voltage is close. But the BAT does not have a reputation as a tube destroyer,
what I’m asking is where would upgraded preamp tubes have the most impact? |
I’m a tube rolling proponent , so I would say yes to both questions, but how much improvement you would hear or what brand of tubes would sound best to you, I can’t say. If you go to tube dealer Brent Jessee’s website: BRENT JESSEE RECORDING HOMEPAGE (audiotubes.com) He has broad, general descriptions of the sound of various tubes. The only problem is that they may not sound that way in your gear, in your system. You can call any of the people I mention and they will talk to you about what tubes you might like, and I have read many posts saying that all three have given the callers excellent advice. Maybe people with the same components as you will chime in, but I also suggest calling the maker of the gear for advice. NOS tubes have gotten expensive, like everything else, so it’s hard to tell you to experiment till you find what you like. Two other knowledgeable sources of tube advice are: Andy Bouwman at Vintage Tube Services - Great to talk to, has great tubes, good prices, but can be slow. Many people love Andy. Kevin Deal at Upscale Audio - Very knowledgeable but has a very no-nonsense style that some people don’t like. See the thread: Upscale Audio and Primaluna | Audiogon Discussion Forum for opinions and a couple of posts by the man himself. Good Luck and Enjoy! |
