[weinerc]

Here's my story. I just purchased a pair of HD 600 and an ASL MG OTL32 amp from audioadvisor.com and I'm somewhat disappointed. Now granted, I just got the amplifier, I understand there's a break in period, but was rather unimpressed, particular after spending nearly 600 dollars.

Now, I have a Yamaha RX-V1 receiver, which posses "Silent Cinema" (essentially surround sound processing for headphones), but I'm curious about the specifications of the receiver's headphone section? Here's the specifications from Yamaha:

"Headphone Jack Rated Output/Impedance CD, etc, (40mV, 8 ohms)...150mV/100 ohms"

Has Yamaha equipped my RX-V1 with a decent headphone section compared to an external amplifier or should I no longer pretend to be a "headphile"?

Please help!

 

[fewtch]

Try plugging the 600s into a few decent solid state sources, so you can determine if it's the MG OTL32, the headphones, or the combination that you're disappointed with.

The 600s definitely need at least 8 hours of break-in to even *begin* to sound reasonably good, in my opinion (they start out incoherent and shrill in the treble)... I'd suggest some very bass-heavy music, or a low frequency sine wave tone (15 to 30 Hz) played at moderate volume if you want to speed up the process. I don't know how long the OTL32 needs break-in, but if I'm correct it's a tube amp, which will definitely benefit from some break-in time.

P.S... what's your source?

 

[bangraman]

I've had the same results as you on a variety of amps. I found the HD600 (even the with Cardas) somewhat uninvolving. Good, but an 'OK... now what?' phone.


I'd suggest you do what fewtch suggested and see if things improve, or cast around for alternatives.

 

[weinerc]

Thanks for all the help. My source is a Philips SACD 1000.

Can anyone help me understand the specifications of the headphone section? How do they compare to an external headphone amplifier? Better? Worse? Same?

Grazie mille,

Charles

 

[pp312]

Quote:

Originally Posted by bangraman I've had the same results as you on a variety of amps. I found the HD600 (even the with Cardas) somewhat uninvolving. Good, but an 'OK... now what?' phone.

I bought a Jecklin Float a while back and the seller told me he'd listened to a 600 before buying the Float and thought it was crap. I wouldn't perhaps use that word but I tend to agree that it's over-rated--and definitely uninvolving. I'd advise weinerc not to be afraid to dislike this phone if burning-in etc doesn't help. It may be a sacred cow in hi-fi circles but many people, yours truly included, simply can't abide it.

 

[tk_suki]

When I recd my HD650s with Equinox cable. Also, felt rather unimpressed. But had 30days to trial so, did what head-fi recommended. Burned in and it took many days! but eventually they came to light. I have Sony CD3000s which sounded very good from the get go, but now both hold their own in certain areas.

I have a pretty healthy front-end to drive so perhaps that helps. But like you in the beginning was ready to return.

best of luck.

 

[slchang]

Quote:

Originally Posted by weinerc Can anyone help me understand the specifications of the headphone section? How do they compare to an external headphone amplifier? Better? Worse? Same?

Interestingly, someone just asked a question almost identical to this over in the Source forum: http://www5.head-fi.org/forums/showthread.php?t=72148

In general I think it's fair to say that most home receivers put enough power into the headphone jacks to drive headphones fairly loud (since, unlike personal cd players, for instance, they've got a ton of power running around inside to start with), but they don't necessarily dedicate much effort to getting a refined sound into your headphones. Looking at specs, unfortunately, doesn't really seem to give much info on the quality of a home receiver's headphone out.

 

[Eagle_Driver]

Reading that particular Yammy receiver's headphone jack specs, its output impedance is 100 Ohms, with a sensitivity rating of 150mV. The relatively low-numbered sensitivity rating means that a given change in the volume control position will deliver a relatively large change in the actual volume level. (Put it this way, all other things being equal, an output with a 150mV sensitivity rating is noticeably more sensitive than one with a 340mV rating.) And the 100-Ohm output impedance means that relatively few headphones will sound good when connected to that jack (though still a far cry from the really tough 390- or 560-Ohm output impedance that was typical of some other receivers' headphone jacks. Those super-high-impedance jacks demand 600-Ohm or higher-impedance headphones just to avoid sounding like poop!)

 

[JaZZ]

Quote:

Originally Posted by Eagle_Driver ...its output impedance is 100 Ohms, with a sensitivity rating of 150 mV.

I don't think this is really the output impedance (and sensitivity). Looks very much like the maximum voltage at the specific load impedance. 150 mV/100 ohms.

 

[Eagle_Driver]

Quote:

Originally Posted by JaZZ I don't think this is really the output impedance (and sensitivity). Looks very much like the maximum voltage at the specific load impedance. 150 mV/100 ohms.

Not exactly. That rating would have been even more feeble than the voltage output from even the weakest portable player! And that cannot occur in a full-sized component of any type.

By the way, the 150mV output into a 100-ohm load would have resulted in a maximum power output of a horrifically low 0.2 mW! And I do know that 150 mV into a 16-ohm load already resulted in a pitiful 1.4 mW.

 

[lini]

JaZZ: I think Eagle_driver's assesment is correct, as your interpretation would only result in 225 nW (yes that's nano!) output power...

Greetings from Hannover!

Manfred / lini

 

[Eagle_Driver]

Quote:

Originally Posted by lini JaZZ: I think Eagle_driver's assesment is correct, as your interpretation would only result in 225 nW (yes that's nano!) output power...

Yep. That's exactly what I had calculated all along. Even the very weakest of the non-Euro-c(r)apped portable players deliver at least 200mV in voltage output from their headphone jacks.

 

[JaZZ]

erm... I've mixed up mV with mW. My bad. Anyway I'm skeptic about the output impedance. «(40mV, 8 ohms)...150mV/100 ohms». There can't be two output impedances at the same time.

 

[Eagle_Driver]

Quote:

Originally Posted by JaZZ erm... I've mixed up mV with mW. My bad. Anyway I'm skeptic about the output impedance. «(40mV, 8 ohms)...150mV/100 ohms». There can't be two output impedances at the same time.

In this case, then the 8 ohms is the minimum impedance load that the output requires -- and I was somewhat misleading about the voltage sensitivity rating. The mV figures at those specific impedance loads refers to the voltage output that's required to produce a 90dB SPL output with headphones that are rated at 97 to 98 dB/mW. The higher impedance (100-Ohm) figure is usually the nominal output impedance of that output.

 

[JaZZ]

Quote:

Originally Posted by Eagle_Driver The mV figures at those specific impedance loads refers to the voltage output that's required to produce a 90dB SPL output with headphones that are rated at 97 to 98 dB/mW.

Sounds absolutely logical... Hey no, in fact I'm being sarcastic. Never heard of such strange formulas. Sounds Esperanto to me. I still don't believe the 100 ohm output impedance. Nevertheless you may be right in the end.