Lon - Once again your posts are a wealth of info and opinion, and thank you for that. I was intrigued when I saw this post in the Holy Grail Tube thread and looked into these tubes and adaptors. Please keep the info and impressions coming and have a relaxing weekend. Happy listening, Chris.

I just finished screening 25 of the GE JAN5670W.
15 of the 25 had 3% or better section matches for gain.
There were 4 tubes that actually had perfect section matches for gain.
The other 10 tubes fell into 5% section match.
As mentioned in the other thread, these measure very consistent for gain and self noise.
I cant recall if ifi sold these with their adapter for $99 each or $99 a pair.
Doc Bottlehead is using these in their latest mono-block amp offering.
I should have more than enough of these for my use, just a single in my SE84UFO25, so long as they have decent life span.
Though I am still considering a bulk 6N3P-EV or DR purchase.

I used to have an iFi ITube2, a tube buffer which incorporates a GE5670 tube. If memory serves me correctly, iFi indicated that the expected lifespan of the tube, at least in that component, was 10,000 hours.

So I'm guessing that these rugged military tubes should serve everyone a long time.

HK

I agree that they are not stupendous, but are very neutral and easy to tune around, and bargains at this price. I'm receiving a pair soon that are thoroughly screened and matched for the inputs on the Monoblocks, which should give me the clearest window into the tube and its characteristics. Having a six pack in my ZTPRE that are section-balanced has been quite nice sonically, allowing me to play with gain between components and get a slightly more holographic sound than other types I've been using (in my untreated room). Continued use has them seasoning in and the midrange has opened up giving a transparency and tonal frequency balance that is very pleasant if just a tad bass-shy.

All the comparisons I've been able to find between these and the 6N3P seem to indicate the latter are "bright/brighter" so I don't expect too much from that tube type. . . . But we'll see.

Tom and Eric: I don't think you two are using preamps. I can't be without a preamp now, though I did okay with a ZBIT between the DSD and the amp(s) adding a great Decware preamp has helped both my systems out immensely.

I find a certain advantage to having the same tube type and/or family in the preamp and the amp(s) so I was happy to receive a pair of fully matched 5670W to put in the Monoblocks and complete that chain of 5670W in the ZTPRE and the Monoblocks. And I received the sort of homogenous sound I expected, and really am enjoying it. The sound is pretty neutral, with spacious elements and three dimensional. I played around with tubes in the ZROCK2 and with a number of hours on a Brimar that I had neglected for a while I'm getting a really good match with the GE tubes and so I think I'm getting a wonderful overall sound that I'll stick with for a while. Yes, the Amperex 7308s I was running in all the input spots were great, as were the 6N5P from Steve; these GE are offering as great a window into the sound, and are the most affordable of the options, so I'm happy to have discovered them and played with them. It was also worth getting three pairs with balanced triodes for the ZTPRE and a fully matched pair for the amps--channel balance is spot on and I'm getting a strong centered mono image (I listen to a good share of mono!)

Yes, I have "better" tubes on hand too, at least with maximized tube complements etc. And yes, they are MANY times more expensive than the 5670W and not more than ten percent better I'd say. So I really only have "everyday" tubes as I used the system every day and am seeking that one complement to keep in for good. I do have complements that I have embraced for a long time, and I know this is one, and so affordable!

I've now put 5670W into my headphone system in the main system: 3 in the CSP2+ with the 25th Anniversary mods, and one in the Taboo Mk III that it feeds. With any of the rectifiers I have to roll in these components this is a great setup and as good as the all Amperex 7308 version I've used and the Mullard ECC189 version I have used. I hadn't used BOTH the CSP2+ and the Taboo Mk III for headphones before but since I now am using ZMF Ori headphones in this system and they like the double BOOM of these two--very good sound. Only way this could be improved is with a ZROCK2. One day perhaps! I wish a ZROCK2 could have two outputs--that would make my main system complete, though it would mean another pair of expensive interconnects and another great power cord.

Tube Depot has been a big help with this tube type and converter, though I haven't used them exclusively so far. I have a trio of Raytheon 5670W on the way that I plan to try in the CSP3 with Anniversary mods I use in my audio/video system, and I have another GE 5670W from Tube Depot on the way to use in the Taboo Mk IV with Anniversary mods in that system. So I would then have 5670W everywhere and can see how that is (I've tried 5670W in both input positions in this system, nice big deep sound).

I think I'll continue to use these, as they season in they continue to give me great sound and I've tuned isolation and speaker positioning to improve sound a bit further. And at the decent pricing on these from Tube Depot I think I'll slowly over the next months purchase fully tested and screened tubes to replace those that I have bought with just the sections matched. . . . The pair that is fully screened and matched that I do have as inputs for the Monoblocks are sounding really good and channel balance and sonic symmetry is precise.

This has been another layer of tube-rolling fun for me.



As for the preamps. . . . I used to believe I was getting the best without them, but especially when the ZTPRE came into my life, and now with the anniversary mods in the CSP preamps I have. . . there's no doubt that with the right cabling and tubes there's more of all the good properties possible (and I enjoy being able to use more sources). I just can't listen without them now. I tried for a week in the audio/video system--the Taboo Mk IV sounds GREAT on its own, but there's an immediate deeper involvement the minutes the CSP3-25 is back in place! They're an expense, but if you can compare some time you may well find yourself saving up. . . .

I have one more component on the way. Because I moved the CSP2+25 into my main system I need another headphone amp for my bedroom system and I purchased an Oppo HA-1. Been meaning to try one and went for it. I should have it in a week or so. . . and I'm suspecting it will be a great match for the Oppo PM-1 I use there.

You should keep thinking of it. They are excellent and really help system sound. I've tried to be without it, and I've tried to be without the CSP3-25 and I miss them within hours of their removal from a system.

Thanks for the update Lon.  Somewhat ugly but reasonably priced rectifier for sure.

I continue to use the 5670W as my daily driver.  Good tube!

Well if you say it can hold its own with the Aquas, then looks be damned.

Has anyone compared these tubes to 6922 or 7308 tubes?