[musicman59]

Quote:

Speaking of the Mills resistors:
 
After further evaluation I have removed my Rothwell inline RCA attenuators, as the sound out of my speaker amp is better without them. The background seems blacker and there is more clarity. Then I installed the 10 ohm Mills resistors to equalize the impedance and the imaging improved, I think that there is more depth to the sound now. The unfortunate part is that I am now driving my HE-6 at 9 am on the dial without the attenuators, as the resistors are in parallel and not in series but I can live with that. I would prefer to be closer to my amp's "sweet spot" volume-wise, but it sounds great and there is no channel imbalance. Even if there was some imbalance, the amp has dual mono volume pots so I could compensate.
 
My next goal on that system would be to upgrade my DAC to a balanced one that will upsample to at least 96k (using Devilsound NOS DAC now) so I can adjust my volume down out of the computer digitally without sacrificing any sound quality. The DAC I have set my sights on is the Balanced Havana which would provide a multitude of benefits besides upsampling: a balanced source would match up better with my balanced speaker amp, and it has a tube output stage which my SS amp benefits from as well. This would allow me to drop the tube stage which does increase the volume of the Devilsound preamp-style.
 
But even at 9 am on the dials the sound is better than ever out of my HE-6 now, many thanks to wuwhere for helping me sort this out so far. I am already starting to like this rig as much or better than my other setup which wasn't the case before.
 
I do have another question however, as my math skills have evidently declined somewhat, I think it's an algebra thing (I was better at geometry lol). I am trying to figure out how much power I am putting into the 50 ohm HE-6 exactly with my 45 wpc amp:
 
8 ohms, 45 wpc
16, 22.5
32, 11.25
50, X
64, 5.625
 
I think X may be 7.2 (wpc) but I'm not sure, my secondary conclusion is 8.4 wpc. But I wouldn't be surprised if it was something else entirely. If there's anybody that has the math skills to confirm the value of X I would appreciate it.
 
Also I think that with my resistors in parallel I am not attenuating the volume like I would be if these resistors were wired in series. I believe that the sound quality is better this way?
 

 

 
I tired the same resistors in my Threshold T50 but IMO the sound changed a little bit emphasizing the high frequencies a little bit. I like the sound much better without them.
 
 
 
 

 

[wuwhere]

Quote:

Parts Express is currently selling refurbished Dayton Audio DTA-100 Class-T 50wpc @ 8ohms for $49.90. I picked one up to have an SS amp for my 6. Also my tube amp generates a lot of heat.
 
PS: I know a $50 amp should not appear in the high-end forum.

This amp has been seating for a week or so on my desk since it arrived. Tonight I fired it up. Plugged the 6 in its hp in. Nice.
Its a warm sounding amp. If you feel that your 6 is bright this is the amp for you. I've got the vol at max through the hp out. I need to try
the speaker out.

 

[grokit]

 
Quote:

grokit
 
you're underpowering them ! (joke)
 
Seriously if you look at the table and your calcs ~50w at 8 ohms seems to be the recommendation

Quote:

Nooooo!!  They need moah powwwah! 

Well they appear to be driven quite well as I have very good sound at 9am on the dials, I don't think I would have any attenuation at all if I had any more power. There must be more to the equation than the wpc specs, like how the power is allocated re voltage & current. It's got more power than many amps that have been known to drive the HE-6 quite well, like the Liquid Fire which is rated at 4W into 32Ω, where mine is 11.25W into 32Ω for example. This is a 45 wpc speaker amp, it's got way more power for example than any T-amp I have heard of. Also my tube stage functions as a preamp by increasing the input voltage from the source which seems to bump up the effective output by a significant amount.
 
Quote:

I tired the same resistors in my Threshold T50 but IMO the sound changed a little bit emphasizing the high frequencies a little bit. I like the sound much better without them.
 

Now this could be a power issue if the T50 is rated at 50 wpc into 4 ohms, if it's 8 ohms then it's about the same as my amp but as I said I am bumping up the source voltage with my tube stage. But there is no brightness at all on my system FWIW, if anything the resistors seemed to have actually tamed the high end for me because it sounds better than ever.
 
 

 

[dukja]

I hear exactly the same thing that you described with my Rotel speaker out (60 W for 8 ohm).  Initially, it sounds "clearer" but early fatigue will set in eventually.  Finally I have to remove the resistor and HE-6 sound more "easy" (less high freq stress) and natural to me.
 
Quote:

I tired the same resistors in my Threshold T50 but IMO the sound changed a little bit emphasizing the high frequencies a little bit. I like the sound much better without them.

 

 

 

[wuwhere]

For SS amps, the resistors are really not necessary. But for tube amps they are since most tube amps have output transformers. The affect on sound is a different matter. This is unpredictable. It can only be judged by your hearing and your preferences. And it may also be affected by your equipment upstream.

 

[grokit]

 
Quote:

For SS amps, the resistors are really not necessary. But for tube amps they are since most tube amps have output transformers. The affect on sound is a different matter. This is unpredictable. It can only be judged by your hearing and your preferences. And it may also be affected by your equipment upstream.

 
Right, I didn't install them to protect the amp, just to see if I liked the sound with the impedance equalized between the speaker taps and the headphones. And for me it seems to have worked out well.

 

[dukja]

Understood.  For me, I also just tried it to see if there is any sonic benefit for such a easy mod, not for protection at all.  Unfortunately, it does not seem to work favorably in a long run.  But that is OK.  I'll save the resistor for tube amp in the future.
 
Quote:

For SS amps, the resistors are really not necessary. But for tube amps they are since most tube amps have output transformers. The affect on sound is a different matter. This is unpredictable. It can only be judged by your hearing and your preferences. And it may also be affected by your equipment upstream.

 

 

[wuwhere]

I've got a new amp to listen to my 6, a Dayton Audio DTA-100 Class-T. Very musical.

 

[Loevhagen]

My new HE-6s are scheduled for delivery on Monday and I have already received the HE-adapter. My plan is to hook it to the Abrahamsen V2.0 integrated stereo amplifier (70W @ 8ohm and 140W @ 4ohm, 1500VA). I really have high hopes for that combination; HE-6 being transparent and the Abrahamsen being mid focused with large soundstage.
 
Actually, the Abrahamsen V2.0 is one of the SS I've heard that de facto has that tube sound. I've owned tube amps that sounded less tuby than the Abrahamsen.
 
I love the V2.0 on Klipsch (RF-63), so saying I'm excited is an understatement. I know that high hopes are risky...
 
 

 

 

[musicman59]

Quote:

 

Well they appear to be driven quite well as I have very good sound at 9am on the dials, I don't think I would have any attenuation at all if I had any more power. There must be more to the equation than the wpc specs, like how the power is allocated re voltage & current. It's got more power than many amps that have been known to drive the HE-6 quite well, like the Liquid Fire which is rated at 4W into 32Ω, where mine is 11.25W into 32Ω for example. This is a 45 wpc speaker amp, it's got way more power for example than any T-amp I have heard of. Also my tube stage functions as a preamp by increasing the input voltage from the source which seems to bump up the effective output by a significant amount.

Now this could be a power issue if the T50 is rated at 50 wpc into 4 ohms, if it's 8 ohms then it's about the same as my amp but as I said I am bumping up the source voltage with my tube stage. But there is no brightness at all on my system FWIW, if anything the resistors seemed to have actually tamed the high end for me because it sounds better than ever.
 
 
 

 


The T50 is 50 watts per channel Class A in 8 ohms. I don't think is the source. From my CD transport or Squeezebox the signal goes to my PerfectWave modded DAC and from there to my Threshold T2 pre-amplifier.
 
Since they are not really needed for SS amps and the amp is totally quiet I remove them and kept running without them.
 
 
 

 

[Loevhagen]

Reporting in that the Abrahamsen V2.0 powering the HE-6 is working good and the SQ is within what I hoped for in advance.
 

 

 

[sridhar3]

Quote:

Reporting in that the Abrahamsen V2.0 powering the HE-6 is working good and the SQ is within what I hoped for in advance.
 

Nice picture.

 

[.Sup]

Quote:

Reporting in that the Abrahamsen V2.0 powering the HE-6 is working good and the SQ is within what I hoped for in advance.
 

 

very nice setup Hagen. How much did the amp cost?
 

 

[Loevhagen]

The amp has been with me for some time. Used it with Klipsch RF-63 speakers. Since i tried head-fi (9 months ago), I have not used my home theater nor my full size stereo system. In other words, for me the Abrahamsen amp is "free of charge". Bought new it is $1800. It can be on sale and as "low" as $1100. It has raving reviews and sound more tuby than many modern tube amplifiers. It is also fairly beefy (1500VA).
 
Abrahamsen (www.abrahamsenaudio.no) is founded by Per Abrahamsen (the guy who started Electrocomapniet). 
 
The V2.0 have a large soundstage, is mid focused and acoustic music have a nerve to it it is easy to fall in love with. The HE-6 being so transparent, the synergy is quite amazing. I know it's early to conclude, but having listened to headphones hours avery day since January, I have a gut feeling here. 
 
I love the HE-500 and didn't care too much for the HE-6 when I heard it earlier this year. My deepest appologize to the HE-6 fans. I now know what the fuzz is all about. The HE-6 is indeed a fabulous headphone, if amped to own liking.

 

[sphinxvc]

We'll definitely need to hear what you think of it against the latest LCD-2s.