[cddc]

True...and with adapters more and more new tubes getting in the line

 

[Tom-s]

Fascinating. I've got a Crack and am interested in the benefits to this approach.

For me it's just something i've been wanting to try. With GEC 6080's being very expensive and scarce. I want to compare this as an alternative (and on first impressions, it is).

"Did anyone notice the A2293 is only 0,95A -> more driver options"

Interesting, you mean you've tried them in the 12AU7 socket?

No. Absolutely not. Don't plug them in the driver socket.
Crack uses a 3.5A power transformer. Normally 2.5A 6080 + 0.9A ECC32 is max. What i meant was, that with only 1.9A total for the power tube, there's 1.6A room for the driver tube. There's only a few extra options to try with Crack.
For now. The only real world advantage of this lower power consumption is a cool running Crack on a hot day .

 

[cddc]

Thanks a lot for the clarification, Tom! Obviously I made a mistake yesterday without checking the specs of A2293. I thought 0.95A is close to 0.9A ECC32, hence could be used to replace ECC32 in the 12AU7 socket.

I checked its specs today, A2293 is rated for 0.95A, so running a pair would be 1.9A, which is too high for the 12AU7 socket. However, if used in the power tube socket, 1.9A is sort of low compared to 2.5A 6080, is the dual A2293 going to be as powerful as 6080 when driving HD650/800?

I'm thinking of other possible candidates, but not sure if they can be used in Crack. Say, we use 0.3A 12AU7 as driver, then we will have 3.2A headroom for the power tubes, so has anyone tried 1.27A KT66 / 1.5A KT77 / 1.8A KT88 or 2.54A dual KT66 / 3.0A dual KT77?

 

[m17xr2b]

A2293 is rated for 0.95A, so running a pair would be 1.9A, which is too high for the 12AU7 socket

What?

so has anyone tried 1.27A KT66 / 1.5A KT77 / 1.8A KT88 or 2.54A dual KT66 / 3.0A dual KT77?

What????

Don't take this the wrong way, you don't know what you're doing spec wise with tubes and it can be extremely dangerous, transformer meltdown flying sparks dangerous.

 

[cddc]

LOL....I'm asking potential candidates to try with Crack, not sure if they will fit in Crack though

 

[cddc]

You know the 6080/6AS7G family has limited members. If we can have some breakthrough into other family of tubes, it would be very encouraging.

 

[DenverW]

After spending a good amount time rolling all kinds of tubes, such as e80cc, 12bh7a, dual 7193, dual cv6, e1148, 6sn7, 6j5, 6f8g..

..I've come to the conclusion personally (YMMV!) that the crack just seems to work best with the tubes it was designed for: 6as7/6080 type and 12au7 type. I found a larger improvement in sound quality doing the bottlehead power cord than I did using 6sn7 tubes.

I've never really found an appealing power tube with adapter variant to try.

 

[BobMonkhouse]

Just wondering if there's another pair of headphones that can come close to the sound signature of the HD650 paired with the Crack!?

 

[DenverW]

Does price matter? I've tried both an hd800S and SDR modded hd800 (my current headphone). I would recommend both over the 650. I think the 650 is the absolute best value on this amp price wise, because it can be found under $200 easily (6XX), but its not the BEST pairing. I preferred my Beyerdynamic Amiron over the 650, both in sound and comfort. Lots of high impedance headphones will match well with the amp. Beyer T1, 1990, Amiron...ZMF offerings...HD800, all great. The matchings can be somewhat tube dependent, for example if you match the T1 with a bright Westinghouse 12au7 it can really have sharp treble.

But for the price? The 650 can't be beat, which is why its so often recommended for this amp. If I misunderstood your question and by 'close' you mean sound signature instead of overall sound quality, I would say possibly a zmf such as an atticus, Aeolus, or eikon. Hope this helps!

 

[BobMonkhouse]

That was exactly my question, you got it right, and I didn't think about the price point but rather improving on the HD650 experience with similar sound signature.

Actually, I love my HD6XX/Crack combo. I've listened to HD800 hooked up to SS type of amps but it's not for me, it's too lean and hot sounding from what I remember.

In the same price range, I'm curious about the ATH-R70X. It sounded quite neutral when I demoed it at a meet-up but don't know if it's going to be a good alternative with the Crack.

 

[DenverW]

I don't think it would be a major upgrade from the 650, especially if you like the sound signature on the 650. I would say a big upgrade without losing somewhat of what you like in the 650 would be either a ZMF atticus or an HD800S. The S is changed enough to lower the treble spike, much similar to the SDR modded 800.

 

[BobMonkhouse]

Good info here, thanks! Do you know where T1 stands against HD800 and HD800S?

 

[DenverW]

I found it a bit too bright for my tastes. For Beyer my favorite sound signature was the amiron.

 

[Wes S]

Just wondering if there's another pair of headphones that can come close to the sound signature of the HD650 paired with the Crack!?

The ZMF Aeolus, without a doubt. I own the BHC Speedball, HD650, and Aeolus. I can honestly say, that the Aeolus improves on every aspect of the HD 650 while maintaining a similar sound with the BHC, and it is a match made in heaven.

 

[raindownthunda]

The ZMF Aeolus, without a doubt. I own the BHC Speedball, HD650, and Aeolus. I can honestly say, that the Aeolus improves on every aspect of the HD 650 while maintaining a similar sound with the BHC, and it is a match made in heaven.

Couldn't agree more!