HifiMAN HE-6 Planar Magnetic Headphone

[Skylab]

Quote:

If you want to go for the better solution, it will cost you a little more:
 
For 8 ohm tap:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=005-12.5
 
For 16 ohm tap:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=005-30
 
 

Thanks Kevin!  Very very helpful as always!  I will order some of those - I am no stranger to Parts Express
 
 


Quote:

Because of your earlier post about headphone Jack in a speaker amp I ran my complete system though my Onkyo 7.1 120W per Ch speaker amp using the direct audio function for headphones (source direct) 2Ch interconnect inputs of my Onkyo and the 1/4" headphone Jack with my HE6's. The good news was there was more than enough volume to blow my ear drums, the bad news was the audio compared to my WA5LE and tubes sucked, not even close. If I had no WA5LE and tubes to plug in my HE6 and only my Onkyo I would go back to my WA6SE and my HD-800's.
 
Sorry to hear no Leben with your HE6's.
 

Yeah but the difference is that the headphone out of my vintage Pioneer receivers sounds absolutely outstanding - better than any SS headphone amp I have ever heard.  These 70's high end receivers are on a very different level than any mass-market surround receiver is today.
 

 

[kwkarth]

Resistors paralleled with the 50 ohm HE-6....  Good or bad?
 
The resistors I mentioned in reference to using the Leben to drive the HE-6 from its speaker outputs present a perfectly acceptable load to the Leben transformer to keep it happy.  The unavoidable downside to this is that the resistor takes the lion's share of the power delivered.
 
 
For a solid state amp, it's not necessary.  For an OTL tube amp it's downright bad altogether.  
 
Bottom line, you only need the resistors if you're trying to use a transformer output, tube amp, to keep the transformers happy.  Truth be told, at the minimal power levels we're talking about for headphones, it probably won't do any harm to use the headphones without the resistors.  If it's a noisy amp, the resistors may actually help make things quieter.

 

[wuwhere]

Yes the resistor sucks power but not really that much in my case. With my source's output at 2v, I can comfortably listen between 10 to 13 from the volume control depending on the music track. My tube amp is rated 10wpc @ 8 ohms. I also noticed that the highs on the HE-6 toned down a little bit which is not necessarily a bad thing.

 

[kwkarth]

If we're talking about an 8 ohm tap on a transformer coupled amp, using a 10 ohm resistor in parallel with the 50 ohms load of the HE-6, the resistor get 80% of all the power output from the amp.  The headphone gets the remaining 20%.
 
So for every 1W of output, 800mW goes to the resistor, and 200mW goes to the headphone.  To actually get 1 Watt to the headphone, the amp has to deliver 5 Watts output.  The resistor soaks up 4W and the headphone gets the remaining 1W.
 
Hope this helps.

 

[wuwhere]

That resistor is quite a hog. Good thing I have 10 watts until I get my 70wpc Audio Research tube amp.

 

[Skylab]

Yeah, the more I think about it, it just doesn't make sense for me personally to bother. I'm mostly using the Leben with the R10, and the HE-6 is getting used with the Mini-Torri, or my vintage receivers, which really make them sing. So I should just leave well enough alone - plenty of amps around here to do the different jobs.

 

[wuwhere]

Sky, X2. You have plenty enough amps for the HE-6.

 

[Wedge]

The way I see it, the whole 1:2 ratio with the trafo most has to do with heat.  Depending on the construction and design of the trafo, some will be able to handle more heat than others.  So in the case of the Leben which probably has irons in it that cost 3 times the cost of the musical paradise, it can probably handle a more significant load on it than the trafos in the Musical Paradise.  Heat in an amplifier assuming your not just overdriving the amp in general, is a function of how long your using it for since most headphone stuff is Class A is 100% on all the time.  I guess on a side tidbit many Class A amps would actually run cooler in saturation (or compression whatever terminology you prefer).  So in the end it all comes down to part stress, whether you have tube or solid state, really anything that operates outside of what it was designed for lower the life expectancy.  I look at it like this if you plug 600 Ohm headphones into say the Leben headphone port, you easily have the same problem if not worse, actually you probably have the same problem with high impedance headphones with a lot of stuff we plug them into, and somehow we over come this.  Just my 2 cents.  

 
BTW guitar amps are not famous for using really high end magnetics.  Sorry for the terminology change, by iron, magnetics, trafos, I mean transformers in case anyone wasn't sure.

 

[singh]

what about the resistor box that Head-direct was supposed to launch ( which was to be used with high wattage speaker amps ) ?
 
 

 

[SP Wild]

Excellent discussion regarding tube amplifiers and output transformers, very enlightening.
 
Quote:

nah, you only need ask George Ohm, or failing that, Mr. Google.
 
these two links should answer most of the questions concerning impedance load mismatching with tube amps:
 
http://www.prestonelectronics.com/audio/Impedance.htm
http://www.geofex.com/tubeampfaq/taffram.htm
 
the first is a good primer for understanding Ohm's Laws; the second link delves into all things tube amp-related. it is exhaustive and comprehensive. highly recommended reading for those who are interested in the technical aspects of their gear.
 
for those averse to technical treatises, here's a brief summary of the issue:
 
a general rule of thumb for tube amps is the allowance of impedance loads up to twice the amount of the output impedance of the amp. a lot depends on the quality of the output transformers though, so while this may be safe for some amps, it may pose a danger to others. if in doubt, you should probably consult with the designer of your specific amp.
 
however, presenting a high impedance load that exceeds the tolerance of a tube amp can damage the output transformers and output tubes.
 
using the "garden hose" analogy from the first article, where the water pressure from the tap represents the voltage, the nozzle on the other end of the hose represents the impedance, and the actual flow of water out of the nozzle represents the current, problems can arise if the nozzle only allows a trickle over an extended time, which is the case when a too high impedance load is presented. the water pressure can build up inside the hose and it could spring leaks.
 
similarly, with an excessively high impedance load, energy can get stored inside tube amps, high voltages can build up with nowhere to go, and voltage spikes can occur that can penetrate the insulation of the transformer, and short the windings. in the same way, voltage spikes can penetrate the insulation of tube sockets or flash over them, and a permanent short can occur.
 
just to be open and clear, i am no "hard-core tube techno-expert," just a messenger.
 
 
 

Interesting article with the tube amplifiers.  I have always wondered why we are not supposed to turn a tube amp on with nothing connected.  I have asked this question but never understood the answers given.  But this article made it clear to me...open loop of the output and to a lesser extent, too high a load effectively turns your OT tube amp into an ignition coil.  Not something one wants in ones sophisticated audio system.
 

 

 

[jamato8]

Many modern tube amps can be turned on and left on with no load across the terminals. Cary amps for one do not need a load. It is oscillation that can occur with older tube amps and circuitry that not control this and as mentioned, voltages that can exceed specs and that of the caps, potentially blowing the caps, which is not fun. Older VTL amps needed a load and some of the Quicksilver amps and so on but many newer amps do not. It is always best to check with the manufacture but there is no hard and fast rule. 

 

[ardgedee]

Bottom line, you only need the resistors if you're trying to use a transformer output, tube amp, to keep the transformers happy.  Truth be told, at the minimal power levels we're talking about for headphones, it probably won't do any harm to use the headphones without the resistors.  If it's a noisy amp, the resistors may actually help make things quieter.

Hm. That's somewhat worrisome to me, since I've been running the HE-6s off the 8 ohm taps on my amp. The amp runs hot (thermally), but since I don't have a lot of experience with tube amps, I can't really tell acceptably-hot from too-hot yet.

I'll move the phones to the 16 ohm amps and experiment with resistors. Not too happy about having it eat most of the power; would I be getting more headroom by running the HE-6s through the headphone jack instead instead of speaker taps + resistor?

 

[HiFlight]

Considering that the HE6 consumes less than a watt at any reasonable listening level, I don't think headroom will be an issue regardless of which output you use.  I have been using my amplifier with a 10 ohm power resistor across each + and - of each channel and it never gets even the slightest bit warm to the touch no matter how long I leave the amp on or what volume setting is used.  As I am currently using a pre-amplifier to control the  output level, my amp volume control is at max all the time.   With the resistors and HE-6 connected, my amp is seeing an output impedance of 8.33 ohms.   BTW, it is a Tripath-based amp.  
 
Quote:

Quote:

Bottom line, you only need the resistors if you're trying to use a transformer output, tube amp, to keep the transformers happy.  Truth be told, at the minimal power levels we're talking about for headphones, it probably won't do any harm to use the headphones without the resistors.  If it's a noisy amp, the resistors may actually help make things quieter.

Hm. That's somewhat worrisome to me, since I've been running the HE-6s off the 8 ohm taps on my amp. The amp runs hot (thermally), but since I don't have a lot of experience with tube amps, I can't really tell acceptably-hot from too-hot yet.

I'll move the phones to the 16 ohm amps and experiment with resistors. Not too happy about having it eat most of the power; would I be getting more headroom by running the HE-6s through the headphone jack instead instead of speaker taps + resistor?

 

 

[kwkarth]

Quote:

Quote:

Bottom line, you only need the resistors if you're trying to use a transformer output, tube amp, to keep the transformers happy.  Truth be told, at the minimal power levels we're talking about for headphones, it probably won't do any harm to use the headphones without the resistors.  If it's a noisy amp, the resistors may actually help make things quieter.

Hm. That's somewhat worrisome to me, since I've been running the HE-6s off the 8 ohm taps on my amp. The amp runs hot (thermally), but since I don't have a lot of experience with tube amps, I can't really tell acceptably-hot from too-hot yet.

I'll move the phones to the 16 ohm amps and experiment with resistors. Not too happy about having it eat most of the power; would I be getting more headroom by running the HE-6s through the headphone jack instead instead of speaker taps + resistor?

Doubtful, but I can't answer that question without knowing more about your amp.  What amp are we talking about?
 
 

 

[ardgedee]

@kwkarth: I'm using a very old Fisher X-202-B tube integrated amp. Approx. 30 wpc/8 ohm and transformer output.