[justin w.]

things are coming along. the power supplies were tested this week. found a couple where fuses had not been installed, a few where the PCB assembly company put in the wrong diodes, had 1 backwards diode, 1 transformer connector incorrectly inserted that caused a low voltage board to blow up, and 1 bad high voltage transformer. so not too bad..now that that's out of the way, they can be connected to the amplifiers. first the DC balance/offset will be adjusted (what people call the 'bias'), and if that works, the amp is most likely fine. distortion and frequency response will be tested. the amp will then run for 1 week at 75-80F ambient temperatures, with 100 power cycles at random intervals. the amp will then be run for 2 hours and have the DC balance/offset adjusted at 75F ambient temperature. the distortion/frequency response will then be tested again, and compared against the original measurement. then an audio source and headphones will be connected for a low tech test of the inputs/outputs. then all of the top cover screws will be installed, all other screws will be tightened, the amp will be cleaned and packaged
 

 

[David1961]

I agree with what Julian has written, but would've liked to have used both my interconnects with both amps. Julian's KGSSHV only has XLR sockets so we could only use my silver cable XLR's with his KGSSHV and my copper cable RCA's with my BHSE.

( From using both those interconnects with my BHSE I've found with the silver XLR's the sound is more detailed and transparent, whereas with the RCA's the sound is warmer. )

I would also have liked to have tried the stock Mullard tubes with the BHSE, because if that had happened I think the KGSSHV might have sounded as good as the BHSE ( this is while using the 009's ) but I feel the 009's driven by the BHSE while using the PH tubes is something all head-fiers should try and get to hear.

In the listening session there were only two songs that I've heard several times before which both are by Rammstien, so obviously I would need a lot more time with both amps to have a better idea on the differences, but in the short time I was very very pleased with what I heard from the 009's driven by the KGSSHV, but out of the two amps though I still preferred the BHSE.

 

[Ali-Pacha]

Good news for this third batch 

Are supporting spikes this shape (curved and black) now ? When yes, I like it 

 
Ali

 

[justin w.]

all the feet right now are rubber, i switch to the metal ones (if that is what was ordered) when packaging the amp. this is so the feet do not get damaged or damage any tables during assembly/testing

 

[David1961]

I might've mentioned this before, but when I was using the stock mullard's and SED's with the BHSE driving the 009's, I was mostly using my copper cable RCA's. This is because when using the silver cable XLR's I found the SQ from certain songs was too uncomfortable, however using the PH's I mostly use my XLR's.

 

[astrostar59]

I might've mentioned this before, but when I was using the stock mullard's and SED's with the BHSE driving the 009's, I was mostly using my copper cable RCA's. This is because when using the silver cable XLR's I found the SQ from certain songs was too uncomfortable, however using the PH's I mostly use my XLR's.

Hi David. So the ttreble lift or detail lift was the change between XLR to RCA?
I am trying to see if there was a dynamic boost and bass boost as well using XLRs. I know the sound level is 6 db higher with your K-01 and XLRs.

The balanced v single ended debate is huge, and there are fans in both camps. I know Audio Note favour single ended but they use mainly tube amps with single ended topology (not DC Coupled). I also read a great article by Lampizator that says true balanced can and hardly ever happens, as it would technically would require 2 identical transformers with the huge cost involved. If on most case, balanced topology is thus a level / ohms test on the line, and a subsequent level boost, it may not affect anything sonically. I understand balanced can reduce hum on long interconnects, but that doesn't really apply to our headphone set ups.

Interesting.

Another subject for the Stax thread, I think all my Stax phones need half an hour of playing music to come on song. I notice the volume goes up after half an hour, as though they need to be 'charged' Has anyone else noticed this?

 

[David1961]

Hi David. So the ttreble lift or detail lift was the change between XLR to RCA?
I am trying to see if there was a dynamic boost and bass boost as well using XLRs. I know the sound level is 6 db higher with your K-01 and XLRs.

 
When using the stock mullard's and SED's with my RCA's plugged into my BHSE, the songs I had problems with did still sound uncomfortable, but less so than when using my silver cable XLR's.
However, I've done what you asked, that was to try again my XLR's and RCA's with the BHSE but this time I tried them with the PH tubes.
The difference was less so than what I found when using the stock mullard's and SED's, but this time the XLR's sounded the better of the two interconnects.
When I did this comparison I had the K-01 setting at 0dB not +6dB which can only be done when using XLR, this allowed me to keep the volume the same using both interconnects, and I found from using the XLR's it was like sitting in the front row, whereas with the RCA's it was more like a few seats back, the difference I found was only slight, but I could still hear it.
 
Now please excuse me but I'm going to do a bit more listening. 

 

[astrostar59]

Maybe in a year or so (HaHaHa) i can tell you the difference between the two.

Actually, i use a KGSS for the 007mk2 and the 009.
Typically, comparing to the Stax tube Amp, the SolidState amp is brighter, maybe a bit too bright on the 009. But with the 007/KGSS there is still a loss of detail in sound.

The dynamic and the power advantage of the KGSS is tremendous. Might be more extreme with a KGSSHV, but i think for a 009 the KGSS is enough power and it gets not as hot as a KGSSHV.

Hi Karl
You buying the BHSE thern? I am not sure about the KGSS, but I would say for sure my KGSShv is less bright in balance than the BHSE and that is with PSVanes that tamed it a bit according to David.
I think you will be ok with the 009s and the BHSE but the DAC will affect the final sound balance. David's K-01 is meaty and quite smooth. My little Metrum DAC did not suit the BHSE and the 009s.

I still have to hear my Audio Note tubed DAC with my KGSShv as it is back in Spain. I will post in 2 weeks when I get it hooked up.

I would also suspect the on-board KGSShv will sound different to the off-board, as the current supply is double, and 4 times at the output (confirmed by Kevin G).
He said that would result in a smoother treble and I would guess a stronger bass and dynamic headroom.

 

[astrostar59]

When using the stock mullard's and SED's with my RCA's plugged into my BHSE, the songs I had problems with did still sound uncomfortable, but less so than when using my silver cable XLR's.
However, I've done what you asked, that was to try again my XLR's and RCA's with the BHSE but this time I tried them with the PH tubes.
The difference was less so than what I found when using the stock mullard's and SED's, but this time the XLR's sounded the better of the two interconnects.
When I did this comparison I had the K-01 setting at 0dB not +6dB which can only be done when using XLR, this allowed me to keep the volume the same using both interconnects, and I found from using the XLR's it was like sitting in the front row, whereas with the RCA's it was more like a few seats back, the difference I found was only slight, but I could still hear it.

Now please excuse me but I'm going to do a bit more listening. 

So sitting further back as regards treble level, i.e. brighter, or is it just more of everything i.e bass power, dynamics, drive as well?

 

[David1961]

So sitting further back as regards treble level, i.e. brighter, or is it just more of everything i.e bass power, dynamics, drive as well?

 
Using the XLR's the sound is more of everything over the RCA's, but only slightly, however when using the PH tubes with both interconnects the SQ is very comfortable, in fact I'd better be careful with my hearing because I keep wanting to turn the volume up which is something I'd never do when using the stock mullard's and SED's. 

 

[Bones13]

things are coming along. the power supplies were tested this week. found a couple where fuses had not been installed, a few where the PCB assembly company put in the wrong diodes, had 1 backwards diode, 1 transformer connector incorrectly inserted that caused a low voltage board to blow up, and 1 bad high voltage transformer. so not too bad..now that that's out of the way, they can be connected to the amplifiers. first the DC balance/offset will be adjusted (what people call the 'bias'), and if that works, the amp is most likely fine. distortion and frequency response will be tested. the amp will then run for 1 week at 75-80F ambient temperatures, with 100 power cycles at random intervals. the amp will then be run for 2 hours and have the DC balance/offset adjusted at 75F ambient temperature. the distortion/frequency response will then be tested again, and compared against the original measurement. then an audio source and headphones will be connected for a low tech test of the inputs/outputs. then all of the top cover screws will be installed, all other screws will be tightened, the amp will be cleaned and packaged

Thanks for the update Justin. Getting close!

 

[caseyse]

Been enjoying my Electra w. 009's and a Debussy DAC and I can't wait to receive my Silver BHSE in this upcoming batch.  It's been a loooong wait, but I know it's going to be worth it!  Trading in my Debussy and will be pairing the BHSE w. a Vivaldi DAC.  I don't like treble too relaxed and didn't like the PH's in the Electra, but will give them a try in the BHSE.  

 

[Rico613]

Congrats on the incoming Vivaldi and BHSE.   dCS Debussys come up regularly on Audiogon from people trading up to the Vivaldi.  It creates a nice opportunity for anyone wanting to snag some very high-end sound for a semi-reasonable price (around $6k for a used Debussy). 

 

[David1961]

Been enjoying my Electra w. 009's and a Debussy DAC and I can't wait to receive my Silver BHSE in this upcoming batch.  It's been a loooong wait, but I know it's going to be worth it!  Trading in my Debussy and will be pairing the BHSE w. a Vivaldi DAC.  I don't like treble too relaxed and didn't like the PH's in the Electra, but will give them a try in the BHSE.  

When you receive the BHSE, I hope you enjoy it which I'm sure you will. I've never heard the Vivaldi but I've read good things about, it'll also be interesting what you'll think between using the stock Mullard's with your incoming BHSE, and the PH tubes.

 

[Phil95]

Thank you Justin for your follow-up info. But, as usual, the more you know, the more you ask... Hence two questions.
 
1. "with 100 power cycles at random intervals": I've always heard that turning off and on again a tube device at close intervals could damage the tubes. Don't you agree with this?
 
2. Regarding the BHSEs destined for Europe (230V): are they tested while set for US voltage (115V), then set to 230V once the tests are completed; or are they set to 230V first, and then powered through a 115-to-230V transformer during the tests?
 
Best regards