Before I got into DHT preamps I converted my Supratek Chenin from 6SN7 to 2C22 using the adapters shown in the photos. I made them from an empty tube base, a ceramic octal socket, some wire and tube caps. They work great and look cool, too! The 2C22 sounds much better than any 6SN7 I've heard.
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Same here - 2C22 was the best indirectly heated tube I tried before going over to DHTs. It's a shame it doesn't have enough gain to drive a 300b/2a3/45 unless you have very sensitive speakers.
The gyrator would have the same gain as a plate choke, no? It would still be no more than mu=20. That looks like very sensitive speakers or a preamp.
There are lot's of places that sell these, they freely available on Ebay - https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2510209.m570.l1311&_nkw=2c22+tube&_sacat=0 & some here at a daft price - DET20 / CV6 / 6S8S / 7193 / 2C22 Tube - valvesNmore
I just finished a 45 amp with the 6j5 as a driver. Powering a pair of Klipsch RF82 Mk2 (98db sensitivity) they are good for low level listening even from a cellphone. To get the most gain out of the 6j5 they are led biased at 8v and transformer coupled to the 45. Before building I was not certain the gain was enough. The thought was that with 8v bias i could always use an 1:2 inputtransformer, and still have a good headroom left. Turns out I dont need one.
I know I can get them on ebay I was hoping to be able to get them here in the US? Or maybe from a member that either has a couple or will make a couple for me..
Update,
My effort to try the 2C22 tube in place of the 6J5 tubes did not pan out. The 2C22's just had too much tube rush in my pre amp, I put the 6J5's back in and did some swapping of positions and bingo found the right combo!!! I will stick with this now until it doesn't work anymore if ever!!!
Oh yea the 6J5's just sound better in my system also the 2C22's didn't have the high end extension that the 6J5's do...
My effort to try the 2C22 tube in place of the 6J5 tubes did not pan out. The 2C22's just had too much tube rush in my pre amp, I put the 6J5's back in and did some swapping of positions and bingo found the right combo!!! I will stick with this now until it doesn't work anymore if ever!!!
Oh yea the 6J5's just sound better in my system also the 2C22's didn't have the high end extension that the 6J5's do...
You may have gotten some bad 2C22s or poorly made adapters, because the ones I've used were dead quiet, and quite extended in the high end.
2C22 was the best indirectly heated tube I tried before going over to DHTs.
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How so? Its just 1/2 a 6SN7 wearing a 50 MHz hat.
Yes, pretty much but that's not the whole story. At one time I had several 6SN7 and 6J5 variants. I did several shootouts and like others I did find audible differences. My favourites were 2C22 and 6P5G. I thought they were audibly better than the rest. That was in a fairly minimalist SE amp with good power supplies. Subjective of course, but there we are.
The 2C22 is an RF (Radio Frequency) Triode. In its intended circuits neutralizing with a small variable capacitor is often utilized to stabilize its operation. In the applications here that is seldom done. But there are times when a serious designer might include it.
In the example circuit the neutralization is accomplished by the 1.5 pf caps connecting plates to opposite grids. The amplifier was used in broadcast stations on 600 Ohm, coaxial 3-wire cables. The system avoids ground loops & to a large extent other interference that could occur.
All done in SS now. And RF & Microwave links.
In the example circuit the neutralization is accomplished by the 1.5 pf caps connecting plates to opposite grids. The amplifier was used in broadcast stations on 600 Ohm, coaxial 3-wire cables. The system avoids ground loops & to a large extent other interference that could occur.
All done in SS now. And RF & Microwave links.
