[spaech]

  Wow - that was quick. But how does the power at 1Khz (the usual reference point) into the given load (300ohms) translate across the whole spectrum? I.e. what if at 300ohms one amp puts out xxma but at 5khz puts out yyma into the same load? Think that's more the question. You're extrapolating based on the one data point (power at 1kHz) and assuming it's flat right on through the rest of the spectrum. That's not what most are finding when the describe the H-10 as warm and detailed, and the BHA-1 as on the brighter side.

Well according to the impedance graph for the HD800, the difference in impedance between 1khz and 5khz is negligible, so power output should be almost identical. But there might be more to it that I'm not understanding.

 

[DDDamian]

  Well according to the impedance graph for the HD800, the difference in impedance between 1khz and 5khz is negligible, so power output should be almost identical. But there might be more to it that I'm not understanding.

The InnerFidelity graphs show the FR about 6db lower at 5kHz - that's half the output for a given power level. Impedance doesn't change much (looks like about 30-40ohms difference between those frequencies, but as a percentage that's a lot).
 
http://www.innerfidelity.com/images/SennheiserHD800B.pdf
 
Ofc if you look at the Senn FR chart supplied with each one it is almost perfectly linear. But they compare it to a "reference" HD-800 so ofc the deviation from that is very small.
 
All that said, comparing the amps using the same can should rule out the can itself. I really don't understand it based on the linearity specs.

 

[tretneo]

How warm/hot does your H10 get? I have been using mine for a month or so and never really paid much attention to how hot the case, volume knob and top plate gets. After swapping the op-amps I'm paying more attention and there is definitely quite a bit of heat, warm bordering on hot to the touch. Looking at the thread there isn't a whole lot of discussion, anyone have any thoughts to share?

 

[DDDamian]

  How warm/hot does your H10 get? I have been using mine for a month or so and never really paid much attention to how hot the case, volume knob and top plate gets. After swapping the op-amps I'm paying more attention and there is definitely quite a bit of heat, warm bordering on hot to the touch. Looking at the thread there isn't a whole lot of discussion, anyone have any thoughts to share?

Hot to the touch would be a concern, but warm bordering on hot sounds about right. If these things are operating in Class A as they should you can expect good heat output. Wouldn't be too concerned as long as it's got a little breathing room on the top and sides.

 

[tretneo]

  Hot to the touch would be a concern, but warm bordering on hot sounds about right. If these things are operating in Class A as they should you can expect good heat output. Wouldn't be too concerned as long as it's got a little breathing room on the top and sides.

 
Thanks, makes sense. Can anyone think of anything done during an op-amp swap that would lead to increased heat but otherwise normal operation? It's definitely not so hot that I can't keep my hand flat on the top panel but it's certainly noticeably putting out some heat.

 

[Jhya]

I also recently got the Burson Opamps for the H10. The discrete Bursons definitely adds a lot more heat to the H10 than the IC opamps I have previously rolled. If I leave the cover on, the top of the cover will get extremely hot, to the point of burning my hand. I tried putting back the MUSES02 opamp with the cover on, and it was much better and only slightly warm bordering on hot.
 
So, when using the Bursons, I just leave the cover off to dissipate the added heat and the heatsink just feels slight warm bordering on hot.
 
As to my impressions comparing the MUSES02 to the Bursons, I feel I'm using the Bursons much more. I can definitely hear much more micro detail and the soundstage becomes 3 dimensional. Also, I feel the Bursons are smoother compared to the MUSES02. There is a slight harshness on the upper range on the MUSES02 that gives me listening fatigue over long periods. With the Bursons, it's so enjoyable and smooth, I can enjoy the music all night.

 

[tretneo]

  I also recently got the Burson Opamps for the H10. The discrete Bursons definitely adds a lot more heat to the H10 than the IC opamps I have previously rolled. If I leave the cover on, the top of the cover will get extremely hot, to the point of burning my hand. I tried putting back the MUSES02 opamp with the cover on, and it was much better and only slightly warm bordering on hot.
 
So, when using the Bursons, I just leave the cover off to dissipate the added heat and the heatsink just feels slight warm bordering on hot.
 
As to my impressions comparing the MUSES02 to the Bursons, I feel I'm using the Bursons much more. I can definitely hear much more micro detail and the soundstage becomes 3 dimensional. Also, I feel the Bursons are smoother compared to the MUSES02. There is a slight harshness on the upper range on the MUSES02 that gives me listening fatigue over long periods. With the Bursons, it's so enjoyable and smooth, I can enjoy the music all night.

 
Nice, thanks for solving this mystery for me. Excited to really dig in and give the Bursons some listening time. I'm a little concerned about the heat as I don't intend to take the cover on/off but we'll see how hot mine gets, my office is pretty well cooled.

 

[DDDamian]

^^^ yeah good call with the discrete Burson amps - they would run hotter. I hadn't considered you weren't using IC's.

 

[tretneo]

  ^^^ yeah good call with the discrete Burson amps - they would run hotter. I hadn't considered you weren't using IC's.

 
Yeah, a small detail I should have included...

 

[tretneo]

   
Yeah, a small detail I should have included...

 
So, that leads me to my next question. How hot is too hot? If I can keep my palm on the top lid without real discomfort am I relatively safe?

 

[DDDamian]

   
So, that leads me to my next question. How hot is too hot? If I can keep my palm on the top lid without real discomfort am I relatively safe?

That's a pretty good guideline. Many amps run warm. Think of car amps driven hard in the hot humid summers. Similar components. My guess is it's nowhere near that warm.

 

[jaywillin]

day three of burning in for my newly acquired h10, if it gets better then it was right out of the box.....  

 
i'd followed this thread early on, but stopped for a while, i have some catching up to do, really interested in the effect of opamp rolling 

 

[heliosphann]

Finally got my replacement H10. Powers up and sounds great. Too bad there seems to be a small short in the cord connection. I don't think it will be too much of a problem, but the QC on these seems to be asstastic. 

 

[stuartmc]

Finally got my replacement H10. Powers up and sounds great. Too bad there seems to be a small short in the cord connection. I don't think it will be too much of a problem, but the QC on these seems to be asstastic. 

I suggest using a good power cord that has a more positive connection to the three prongs. The included cord is utter crap. If this doesn't fix the problem, then I suggest opening it up an examining the IEC socket wire connections. In particular, make sure the ground wire that attaches to the case bottom via the foot screw is not loose.

 

[vr1]

H10 + LCDs family sounded very good.