[jonathan c]

Hope you love them! I’m also curious to hear impressions; I actually like the 6as7g more than the bendix, but I’d probably be the minority.

I have been using a Tung-Sol (made in U.S.) JAN-CAHG-6AS7G in my Woo Audio WA3 to great musical satisfaction. I prefer this power tube to (m)any of the 6080s that I have tried in the WA3. The 6080s were not disappointing, the TS 6AS7G just stood taller - physically and sonically.

 

[Bonddam]

Here's real good 12au7 that cost a pretty penny. I got two off eBay. I tried Psvane cv181 tube but don't recommend it as it is noisey and through a pop through my VC so now ZMF is replacing the driver for me.

 

[OceanRanger]

Here's real good 12au7 that cost a pretty penny. I got two off eBay. I tried Psvane cv181 tube but don't recommend it as it is noisey and through a pop through my VC so now ZMF is replacing the driver for me.

wow, that just looks awesome. My solid state amp definitely falls short on that coolness factor. Or perhaps I should say that warmness factor.

 

[DenverW]

You guys with your tube porn! Makes me want to post pictures....crackatwoa with brimar el90, the oldest of amperex welded plate 12au7, and some gec power tube with an ugly brown base.

 

[skhan007]

I've spent a few days doing A/B testing with my recently acquired Chatham 6AS7G vs. Bendix 6080.

They sound similar to my ears overall, with the Bendix having more definition in the mids, especially vocals, and the high frequencies. My RME DAC has an PEQ, so if I were to make some very slight EQ adjustments and raise the midrange and highs a dB or two, they are very close. Both are excellent and have great presence in the low end frequencies. I wish I could A/B quickly, but I have to power down, allow the current tube to cool for a few minutes, put in the other and allow it to warm up. That being said, I believe the Bendix has a wider soundstage and separation, where the Chatham is slightly more focused sounding.

My next stop will be the GEC 6080, as I've heard great things and I'm eager to see if that is on-par or perhaps better in any way to what I've currently got.

I was interested in the 5998, but I've been using the search function on this thread and the 6AS7G tube roller thread and noted a lot of mixed reviews. Some guys state it's their favorite in the BHC, while others stated they become unstable/microphonic, no difference is sound to Tung Sol Chatham 6AS7G, or simply too pricey. I know there's no consensus (there rarely is among tube rollers, from what I'm reading), but my main question would be how people would see the Tung Sol 5998 vs. Chatham 6AS7G in terms of overall sound.

 

[Bonddam]

I've spent a few days doing A/B testing with my recently acquired Chatham 6AS7G vs. Bendix 6080.

They sound similar to my ears overall, with the Bendix having more definition in the mids, especially vocals, and the high frequencies. My RME DAC has an PEQ, so if I were to make some very slight EQ adjustments and raise the midrange and highs a dB or two, they are very close. Both are excellent and have great presence in the low end frequencies. I wish I could A/B quickly, but I have to power down, allow the current tube to cool for a few minutes, put in the other and allow it to warm up. That being said, I believe the Bendix has a wider soundstage and separation, where the Chatham is slightly more focused sounding.

My next stop will be the GEC 6080, as I've heard great things and I'm eager to see if that is on-par or perhaps better in any way to what I've currently got.

I was interested in the 5998, but I've been using the search function on this thread and the 6AS7G tube roller thread and noted a lot of mixed reviews. Some guys state it's their favorite in the BHC, while others stated they become unstable/microphonic, no difference is sound to Tung Sol Chatham 6AS7G, or simply too pricey. I know there's no consensus (there rarely is among tube rollers, from what I'm reading), but my main question would be how people would see the Tung Sol 5998 vs. Chatham 6AS7G in terms of overall sound.

The only place I've been able to buy 5998 that I know are tested and matched is Woo. Price for one is $450. I like it in bhc but find 6as7g of any brand a better option. It's just cheaper route. 7236 gives a solid state experience and I got 3 for $150 bucks Woo wants $249 a unit. Difference is I have none military units total units 8. Three are metal base and 5 plastic base.

 

[PsilocybinCube]

Here's real good 12au7 that cost a pretty penny. I got two off eBay. I tried Psvane cv181 tube but don't recommend it as it is noisey and through a pop through my VC so now ZMF is replacing the driver for me.

I had a bad 12au7 do that to an Eikon. It's about as frustrating an experience as you can have in audio.

It's definitely a reminder to unplug before turning on your amp!!!

 

[Bonddam]

Did a 2nd try installed first ken rad 6sn7 had hiss that got lower and lower played some music sounded real good. So went back to the cv181tmk2 psvane and powered on without headphones plugged in waited 30 seconds and a little hum in left side not loud enough to bother music playing. So not sure what I'm listening for but I'll switch back later to my Amperex 12au7 bugle boy tube and I know it's dead silent.

 

[Bonddam]

The amp gets turned on and off with no headphone connected from now on.

 

[PsilocybinCube]

Did a 2nd try installed first ken rad 6sn7 had hiss that got lower and lower played some music sounded real good. So went back to the cv181tmk2 psvane and powered on without headphones plugged in waited 30 seconds and a little hum in left side not loud enough to bother music playing. So not sure what I'm listening for but I'll switch back later to my Amperex 12au7 bugle boy tube and I know it's dead silent.

As much as I like to pump up the 6sn7 as a preferred tube (or a pair of 6j5 tubes) in the BHC, I can't get around the fact that a 12au7 or 12bh7 has always been the most noise-free and fuss-free for me.

I don't know all the rules around the 12bh7 vs. the 12au7, I think you are supposed to have the Speedball. I bought my BHC used from @DenverW and the only modification I've made is the woodworking.

That said, I tell you what, the 12bh7 is a hell of a tube for a small amount of money. The TS is cheap and sounds great. It is super punchy in it's bass, it's got a great soundstage, and good detail. I have it paired with a Chatham 6as7g and that pairing is going great with my Verite Open. With the ZMF Eikon I found it a bit too bright, but the VO is more warm/neutral and the combo feels just right!

The nice 12au7 tubes are approaching crazy territory (along with 6as7, 6080, 6sn7, and some 6j5 tube variants) and it's nice to find a really great alternative that isn't expensive (yet).

 

[Bonddam]

As much as I like to pump up the 6sn7 as a preferred tube (or a pair of 6j5 tubes) in the BHC, I can't get around the fact that a 12au7 or 12bh7 has always been the most noise-free and fuss-free for me.

I don't know all the rules around the 12bh7 vs. the 12au7, I think you are supposed to have the Speedball. I bought my BHC used from @DenverW and the only modification I've made is the woodworking.

That said, I tell you what, the 12bh7 is a hell of a tube for a small amount of money. The TS is cheap and sounds great. It is super punchy in it's bass, it's got a great soundstage, and good detail. I have it paired with a Chatham 6as7g and that pairing is going great with my Verite Open. With the ZMF Eikon I found it a bit too bright, but the VO is more warm/neutral and the combo feels just right!

The nice 12au7 tubes are approaching crazy territory (along with 6as7, 6080, 6sn7, and some 6j5 tube variants) and it's nice to find a really great alternative that isn't expensive (yet).

I just decided to jump and test something I was nervous about. This time around the noise went away and seem to run with no issues. I’m going to buy two easy to drive speakers off partsexpress and uses it as a dummy load for testing new tubes. Just need high impedance with high sensitivity. They’ll have to be able to take loud pop’s.

 

[skhan007]

As much as I like to pump up the 6sn7 as a preferred tube (or a pair of 6j5 tubes) in the BHC, I can't get around the fact that a 12au7 or 12bh7 has always been the most noise-free and fuss-free for me.

I don't know all the rules around the 12bh7 vs. the 12au7, I think you are supposed to have the Speedball. I bought my BHC used from @DenverW and the only modification I've made is the woodworking.

That said, I tell you what, the 12bh7 is a hell of a tube for a small amount of money. The TS is cheap and sounds great. It is super punchy in it's bass, it's got a great soundstage, and good detail. I have it paired with a Chatham 6as7g and that pairing is going great with my Verite Open. With the ZMF Eikon I found it a bit too bright, but the VO is more warm/neutral and the combo feels just right!

The nice 12au7 tubes are approaching crazy territory (along with 6as7, 6080, 6sn7, and some 6j5 tube variants) and it's nice to find a really great alternative that isn't expensive (yet).

Thanks for the tip on the TS 12bh7! I was not aware that this tube existed and have only recently acquired my pair of Chatham 6AS7G. Right now, I’m using an RCA clear top 12aU7, based on some recommendations in this thread. Curious if the TS 12BH7 is a step up? I do have the speedball set up, as well. I was listening to my 6AS7G earlier today. Glorious sounding tube in the BHC!

 

[DenverW]

So yes, before using 6sn7, 12BH7, or e80cc tubes you want to have the speedball upgrade.

The 6sn7, 6j5, 6f8g, and the like can be used without any modifications, just adapters.

12BH7A and e80cc will benefit from some slightly different resistors to bring the currents to optimal crack levels. You can get more Details on the Bottlehead website.

Or you could do what I keep saying I’m going to do and build a three way switch with different resistors to be able to roll all three.

I preferred the Phillips sq e80cc to the 12BH7A.

 

[DenverW]

Combo of repairs and fun tonight. Received a bottlehead S.E.X. kit from a classified 'want to buy' I posted. The goal was to bring it into work and have a nice mid range amp to use there with a wide variety of headphones. I had to do some repairs on the amp when it arrived, but got it up and working. Had it at work this week, and then it just...stopped. Music just cut off.

Tonight I swapped out the alps pot that had been having issues before, and BOOM, its working again. Now for the fun part. Switched out the .1uf dayton caps with .1uf Miflex KPCU caps. In the lower uf range these are very affordable (18 bucks from parts connection) and they are VERY good caps. One caveat on these: the connecting wires are fairly large and will not fit on circuit board connections like the .1 caps on the mainline. Listening on my HD800 (which is a great thing about the S.E.X. amp, it plays pretty much anything and is imho the most versatile of the bottlehead amps) the sound is clear, euphoric, and has just a tiny touch of smoothness that eliminates the dull feeling I get with some solid state amps. (I'm looking at you, drop THX!)

If you want an amp that plays anything, including planars, and don't want to fall into the tube swapping pit (they pretty much all sound the same on the S.E.X.) this is the amp for you.

 

[Bonddam]

Edit