I reread your initial post and realized you went from mid 1950s chrome top GTA to a tall bottle version of essentially the same tube. My change the other night was to the first tubes you mention and I really like them a lot. The change tonight is not the same as yours - my switch is to early 1950s tall bottle, clear glass GT. They seem to go as deep as the GTA but not quite as detailed down low and in fact sound a little bit fat at the bottom. Mids are similarly forward as the GTA, perhaps just a little less so. High end is softer, detailed but not as airy. Generally seem less lively, somewhat less dynamic. But in truth, another very acceptable and fine sounding Sylvania. Which is to say, less tubey sounding overall than the typical RCA. I want to go back to the GTA, but instead tomorrow I'll pop in the other Sylvania I have but not listed to: the GTB from late 50s, also a chrome top. Cheers, Robert
Jacmusic in Germany has a 7N7 version of the Sylvania VT231 for 45 euro each. Would need to also get a 7N7 to 6SN7 adapter (I like the Woo Audio adapter). I have some of the standard Sylvania 7N7 tubes that Jacmusic sells. And also a pair of 1940-1945 Philco 7N7 tubes with the insides of a VT231 that Jacmusic had (since sold out). But they still have stock of another flavor of the VT231 as a 7N7. Could be worth trying if you're unable to get a true VT231 that works cleanly in your amp.
You and I are on the same path. I've been rolling tubes in the driver position of my amp. I was loving the Sylvania GTA with it's top-end air and energy. But, they were too revealing of harsh digital recordings. Next I tried GTBs. They are so different than other Sylvanias, fantastic 3D soundstage but they lack the signature top-end extension. My system is revealing and lively so I really didn't miss that extension. I used these for a few months, but a change in my DAC tubes caused a systemic change, mainly a lack of highs. I recently installed some 1950s clear GT's, the 2-hole plates not the Bad Boys. These are good balanced tubes (they don't get much love). My findings are similar to yours, it's not a lively tube, less air than other Sylvanias, but the highs and mids have a sense of realism. They're a good driver tube for sure. My amp uses 4 input tubes for gain. That's where I've got the primo tubes, Ken Rad VT-231 and Sylvania VT-231.
I mean I guess we're all influenced to some degree when we read about the characteristics of a tube's "sound" and then experiment ourselves. But honestly I can't keep them all straight in my head to know what I "should" be hearing when I change a pair out... So I just write what I hear and it's pretty cool when someone else comes in later and says, "yeah, that's pretty similar to what I heard". I did put in some late 1950's Sylvania GTB chrome tops on the weekend. Funny, they look exactly like the GTA that so surprised me earlier - I mean, they look identical in every way. Yet they surely did not impress me like the A did. Unlike you I didn't find their soundstage to be anything special and they really showed themselves to be not particularly dynamic. I agree the top end was not as revealing as the A and it didn't have the more forward midrange either. This all sound rather critical of the early Syl GTB, but in fact it's a reasonably good tube. I know others disagree about the new production Electroharmonix, but I like it as a workhorse tube that does nothing wrong - and I would say the same about these particular GTBs, in fact they are quite similar to the EH with slightly less top end. Keep in mind that when I'm swapping tubes in my system, they are the only two tubes in the chain. I'm running single-ended only, so my Cary SLP-05 is only using two of the six tubes. And I'm running a 50 year old SS power amp known to be smooth. Cheers, Robert
It is interesting that we're finding similar results when rolling these tubes, yours in a preamp and mine in an amp. Can I presume you're rolling the gain stage tubes? Regarding the GTB's, they don't have the typical Sylvania magic, highs are rolled-off and nothing special about the midrange. In my situation, pairing them with Sylvania VT-231's made for holographic imaging that was addicting.
Yes, the L/R positive phase gain tubes are all that is used for singled-ended use in my preamp. Agreed, I can see how pairing tubes with complimentary characteristics could really help dial-in the sound. Cheers, Robert
I know we're talking about best NOS, but let me digress for a minute. Has anybody tried the Shuguang WE6SN7? I ask because they're being compared to vintage tubes even though Western Electric never manufactured a 6SN7. And there's some buzz about WE USA introducing a new 6SN7. Anyone?
Hopefully, someone can share his or her thoughts on the experience, especially the reliability as well.
I’m in the process of evaluating the new US made Western Electric 6SN7 tubes now. There is a thread here all about it.
Found it, thanks so much for answering my query. You Canadians get everything first... no, not really. I'll be following your progress.
I suppose one very valid attribute description I can provide after some extended listening to these new WE tubes in my system is a play on words in the title of the Johnny Nash composition as: “I Can Hear Clearly Now".
Keep in mind that when I'm swapping tubes in my system, they are the only two tubes in the chain. I'm running single-ended only, so my Cary SLP-05 is only using two of the six tubes. And I'm running a 50 year old SS power amp known to be smooth. Cheers, Robert[/QUOTE] I thought that the Cary used the first 2 pair from the left side for single ended, the next pair is for balanced and the last pair is the headphone amp. So don't you need to swap 4 tubes for single ended?
I thought that the Cary used the first 2 pairs from the left side for single ended, the next pair is for balanced and the last pair is the headphone amp. So don't you need to swap 4 tubes for single ended?[/QUOTE] correct i have the slp 05 too (what a great sounding unit) the single ended circuit does use 4 tubes, tubes 1,2 4 and 5, the left two rows. the left most are for left channel gain buffer, positive and negative, and the next row is for the right channel pos and neg. the left 4 tubes should also be a matched quad if possible. the third row, tubes 3 and 6, are for the balanced input. the far right row, tubes 7 and 8 are for the headphone amp.
Why would you need positions 4 & 5, the negative phase gain for L & R, in a single-ended only configuration? You would need the four (1,2,4,5) if you were single-ended input and balanced output - perhaps that is what you mean? But this is not possible for me since my power amp is RCA input only. Cheers, Robert
ok the post above included a double quote inadvertently. front row, left to right 1, 2, 3, 7 back row, left to right 4, 5, 6, 8 7 and 8 are for headphone amp 3 and 6 are for balanced input (buffer). if you have no balanced input sources disregard these two. 1 and 4 are for left channel , one pos, one neg. all inputs, all outputs . 2 and 5 are for the right channel, one pos, one neg. all inputs, all outputs. i believe there is no distinction whether single ended or balanced output.
tubes 1,2,4 and 5 should be a matched quad but you can use 2 matched pairs for 1,2 and 4,5. if you have balanced sources, tubes 3 and 6 can be the same as the others but can also be different to fine tune balanced sources if needed.
Thanks Tony, I'm crystal clear on which tube is which but it's a good reference for someone unfamiliar. However I think you are mistaken as to which tube is used in different configs. This was the subject of my query directly to Cary shortly after I purchased my SLP-05 and the following is cut/pasted from their email reply. "Robert, If you use single-ended in and out (no XLR balanced inputs or outputs) then the signal is only going though tubes 1 (left) and 2 (right). These should be a matched for gain pair. If you use single-ended in and balanced out then tubes 1, 4, 2 &5 need to all be the same manufacturer. If you use balanced in and balanced out then all six tubes matter. 1 and 2 need to be a matched for gain pair. 4 and 5 need to be a matched pair. 3 and 6 need to be a matched for gain pair Steve" Cheers, Robert
Thanks for the follow up Robert and Tony - I have balanced out and either single ended or balanced in depending on source. I keep a matched quad in 1,2, 4 and 5 and a matched pair in 3 and 6
Thanks for that, you actually jogged my memory that I had a follow up question to Steve. It's perhaps an oddball configuration but worth pasting here to complete the picture for posterity. The question was about a balanced source with a single-ended output. "Robert, If your using balance in and then single ended out you are essentially using the positive phase of tube 1 and the negative phase in tube 2 even though the input balance is using 4,5,3,6. Using balance in and balance out will get you better gain. Steve" Cheers, Robert
the need for the same manufacturer is puzzling since many variations of NOS 6SN7 can be made by the same company and have different electrical specifications.
I agree. The reply from Cary is crystal clear in terms of which tubes are in use for the various input/output combinations, but it seems a little odd with respect to "same manufacturer" and "matched for gain" in relation to the character of the sound. But then, I guess two tubes can measure the same (at least, electrically) and sound different, so the priority from them would be to keep things electrically balanced and the sound is in the ear of the listener. After all, when I asked for the information it was framed in the larger context of "tube rolling". From a manufacturing standpoint they obviously choose the production efficiency of all tubes the same. My take away is that it's important for the positive phase tubes (1 & 2) to be the same - matching brand, model and gain. The negative phase tubes (4 & 5) should likely be similar but I don't think gain needs to be matched with the positive tubes, based on my limited understanding of balanced vs. single-ended. And obviously if you're you're using a balanced source, the input buffer tunes (3 & 6) should also be same brand, model and gain. Cheers, Robert
with my slp05 i tried using the single ended outputs with a good quality cable and the sound became less 3 dimensional and somewhat collapsed. very noticeable when i switched back to balanced out. possibly suggesting that slp 05 users could hear an upgrade using balanced outs even if it means using an xlr to rca adaptor at the amplifier input.
