[Radio_head]

The previous version was better than the previous version with the gain modified.

 

[Rico613]

 

[AnakChan]

Hi all, giving this a little bump. This past weekend the folks in Tokyo had a Stax amp shootout - we had the BHSE, KGST, my(Radiohead's) Electra. I won't dwell too much about the comparisons and will leave  that to @arnaud to divulge more about the general comparison but will focus more on my Electra and to get tips from other Electra owners on how I could further tweak it.
 
There is the peculiarity to the midrange "hump" with a hairline more treble edginess giving an overall more aggressive and compressed/congested signature in comparison to the BHSE (and to the opposite end of the spectrum, the KGST which sounded mellow) - all this on the SR-009.
 
I'm using XF2s in my output stage, Electro Harmonix for 2nd stage and Tung Sol 6SN7GTB for first stage. Any recommendations on how to "tone down" the midrange and smooth down the trebles a little? More precisely to the question, is there a methodology to tube swapping the 1st, 2nd stage, and/or output stage or is it more just a trial and error in just swapping all 3 randomly to see what sounds best?

 

[preproman]

  Hi all, giving this a little bump. This past weekend the folks in Tokyo had a Stax amp shootout - we had the BHSE, KGST, my(Radiohead's) Electra. I won't dwell too much about the comparisons and will leave  that to @arnaud to divulge more about the general comparison but will focus more on my Electra and to get tips from other Electra owners on how I could further tweak it.
 
There is the peculiarity to the midrange "hump" with a hairline more treble edginess giving an overall more aggressive and compressed/congested signature in comparison to the BHSE (and to the opposite end of the spectrum, the KGST which sounded mellow) - all this on the SR-009.
 
I'm using XF2s in my output stage, Electro Harmonix for 2nd stage and Tung Sol 6SN7GTB for first stage. Any recommendations on how to "tone down" the midrange and smooth down the trebles a little? More precisely to the question, is there a methodology to tube swapping the 1st, 2nd stage, and/or output stage or is it more just a trial and error in just swapping all 3 randomly to see what sounds best?

 
 
This should be interesting.  What DAC was used?  Was the same DAC used with each amp?

 

[arnaud]

TotalDAC D1-Dual to BHSE (monoprice xlr) > loop-out to KGST (monoprice xlr) > electra (monoprice xlr). Also, a stac SRM 007t2 driven from D1 unbalanced outputs (monoprice rca). All amps were volume matched to ~10mV (out of >40V Rms across stators using 1kHz sine wave). I used my sr009.

My impressions were that the BHSE was well ahead of the others. The KGST was very mellow and tight bass (like a good solid state amp) but felt dynamically compressed compared to bhse along with smaller stage. I would probably really like the kgst on its own (and it's just a good pairing to the 009) but, in direct comparison, I felt the BHSE so much more transparent and closer to the recording. The BHSE was like wire with gain (without sounding harsh or brittle as the source isn't) while the KGST was sounding similar on all musics, always imposing the same kind of signature (mellow / dynamically restrained but very smooth / natural, bit rolled off highs, tight bass but missing sub-bass).
The BHSE had so much kick, it sounded louder even though all amps were level matched within.
The 007t was reminiscent of the KGST but even more rolled off at both ends and dynamically compressed.
The electra was very upper mid centric, with similar highs extension to the BHSE but harsher sounding (who would have thought!!!). We suspect it's the tubes but that will be for another meet...

Had a very brief dacs comparisons but that is much harder to do (need to switch USB output, need to switch amp input, needed to use unbalanced out of the D1 effectively only using half the circu, could not level match). To make matters worse, we were running out of time and got barely 20min to compare the D1 to Lavry DA11 (no comparison), Audio GD M7 (felt much closer to the D1 than all the others) and Invicta (less precise imaging, less instruments separation, less body, but not the HF hash of sabre dacs at all, it sounded pretty good to me on its own).

Also had a brief comparison between my 3+ year old SR009 and the brand new unit one friend brought over. At first I thought the new one was slightly edgier / more upper mids. At the end of the meet, I felt the new unit to have firmer bass and more precise layering / instrument separation as if the diaphragm was better controlled. I would need much more time to properly evaluate due to the subtle changes.

Overall, it was a very very fun day that passed by way too fast. We have to do this again soon, there are so many other comparisons to be made (and more serious dac shoot out).

 

[AnakChan]

It was very enjoyable and more importantly an enlightening experience. Will have to do it again when I get to try other tubes. You're on for another shootout!!

 

[arnaud]

 

[superfred21]

For my electra I use as tube:
 
I'm using Mullard  XF4s in my output stage,  Tung Sol BGRP  for 2nd stage and Mullard  ECC32 for first stage.
 
With this configuration for me the Electra does not sound harsh.

 

[number1sixerfan]

Can anyone confirm that a new version of this amp is still in future plans? 

 

[Rico613]

I'm curious if anyone is interested in a new run of the Electra.  Last I heard the design would include 300B tubes so the sound could be nice indeed.

 

[AnakChan]

Giving this thread a little bump. I have @Radiohead's Electra for the past 2 1/2 yrs and using it primarily with the XF2 tubes for output. In the past 6-8 months I've played around with swapping around the 1st and 2nd stage (currently ECC32 for 1st...yes I know, I know), and STC CV1988 for the 2nd stage.
 
I had the goal to try to tame down the mids somewhat 'cos as per a few posts almost a back the Tokyo Stax folks had a day comparison of the Electra, BHSE, KGST and SRM-007tA, the Electra had pretty prominent mids which was somewhat distracting.
 
Thanks to @arnaud, who's been loaning me various EL34's over the past 6 months for me to demo and try out.

1) PSVane EL34 metal base  - with these, I felt the SR-009/Electra lost the weight in the notes. The trebles were a little gritty and not as smooth as the XF2 as I was used to. Overall the PSVane EL34's weren't my cup of tea - at least for the combination of 1st/2nd stage of tubes I had in hand. Maybe they'll work better in other amps.
2) Amperex XF4 Double D getters - these were more similar to the XF2s with possibly a slight tad better instrument separation. But overall to my ears they felt very very similar XF2's. In comparison to the Telefunkens, the XF4 seems to be a little warmer with a slightly more mellowed treble. The XF4s also sound a little more intimate in comparison to the Telefunkens - a somewhat more "laid back" and organic signature.
3) Telefunken OO getters - these are noticeably different from the XF2s (& XF4s). Whilst the mids are still similar to the XF2/4s, trebles feel more spacious, articulate and airy yet maintaining the smoothness of  the XF2's. This seems to distract my attention away from the mids and gives the overall signature a nicer balance. In terms of depth imaging though, the Telefunkens feel a little "shallower" compared to the XF4s which seems to have a greater depth from front stage.
 
The Electra will never be a match for the the likes of the BHSE however it's still fun to do a little tube rolling esp when friends are generous to contribute to the exercise.

 

[HemiSam]

Nice write-up.  It would be fun to try one of the EC's Electras out of curiosity.  Perhaps someone will surprise me and show up with one at a meet we have in a couple of weeks.  You were fortunate to get to try so many good e-stat amps at one sitting.
 
I hope you have the opportunity to try a Carbon if you have not yet, A.C.  It's taken my 007A's to the next level.  My KGST is 400v and I run GE tubes, but the Carbon is another step up IMO.  More authoritative and it does not take much of the DACT stepped attenuator to make them sing.  It is down low and perhaps in the lower mids where I think they shine the most.
 
HS

 

[AnakChan]

HemiSam, I have the Carbon boards since but just haven't done anything with them. Same with KGSSHv boards. Just been too lazy.

 

[HemiSam]

HemiSam, I have the Carbon boards since but just haven't done anything with them. Same with KGSSHv boards. Just been too lazy.

 
 
Completely understand, A.C.  Not enough hours in the day.  All I can offer is that I believe you will be pleased when you get your hands on a Carbon.  It is still early for me, but early impressions are strong.  I am listening now to some Kevin Eubanks / Stanley Jordan and Marcus Miller...I have never heard the 007A's sound so good...so powerful and moving.  Approaching the bass impact of my TH900's which is a surprise...not quite but much closer now.  I'm using an Ygg for a DAC and keeping it simple....streaming 44/16 files off DEEZER Elite.  Worthy of a listen IMO.
 
Best of luck with the projects...you've got some great ones lined up.
 
HS 

 

[AnakChan]

OK gonna try my luck here (and yes I have also mailed Craig). I've moved back from Japan to Australia and need to reconfigure the to the Australian 230V voltage. Here's what the PSU looks like :-

I'm guessing I need to move the P13 jumper to P18. However why 2 jumpers for 110/110V/120V (see P11/P12)?? Should I :-

1) leave P11 & move the P12 jumper to P16 (220V, 230V, 240V)?
2) leave P11 & P12, but add another jumper for P16?
3) disconnect P11 & move P12 to P16?
4) leave P12 & move P11 to P16?