Using receiver speaker terminals with phones?

[wae5]

Is there a way to use the speaker terminals rather than the headphone jack with K501-K701s on a receiver like the Pany SA-XR55S? I ask because I suspect electrons from speaker terminals are cleaner and more potent than those dribbling from the headphone jack.

 

[kramer5150]

LOL... IE - My headphone jack output sounds like crap, what can I do?

I'm not a proponent of doing what you are suggesting. You are asking the speaker amplifier circuit to perform at operating conditions for which it was never designed or possibly tested. IMHO there is some element of risk involved. What are your headphones worth to you?... is it worth risking them, when you can get a usably good portable amp, pimeta or used LD 2++for $150, that should do the trick.

 

[3x331m]

Quote:

Originally Posted by wae5 /img/forum/go_quote.gif Is there a way to use the speaker terminals rather than the headphone jack with K501-K701s on a receiver like the Pany SA-XR55S? I ask because I suspect electrons from speaker terminals are cleaner and more potent than those dribbling from the headphone jack.

I've tried this receiver with my K1000. I has enough power to drive the K1000, but it does not stop me from searching for better amp for the K1000. It's too clean for AKG.

 

[Zorander]

Quote:

Originally Posted by kramer5150 /img/forum/go_quote.gif LOL... IE - My headphone jack output sounds like crap, what can I do? I'm not a proponent of doing what you are suggesting. You are asking the speaker amplifier circuit to perform at operating conditions for which it was never designed or possibly tested. IMHO there is some element of risk involved. What are your headphones worth to you?... is it worth risking them, when you can get a usably good portable amp, pimeta or used LD 2++for $150, that should do the trick.

Just wondering if you think this can put the speaker amp itself at risk as well.

 

[wae5]

I'm curious if it's possible to do it. I have several HP amps including a Headphonia which is spectacular. Thank you for letting me know this isn't good to do.

 

[kramer5150]

Quote:

Originally Posted by Zorander /img/forum/go_quote.gif Just wondering if you think this can put the speaker amp itself at risk as well.

Good question...
Heres what I see as a theoretical worst-case scenario:

You rig up a cable to adapt the headphones to the speaker wire terminal, no problems there.

You now are presenting the speaker amp (designed for 4-8 ohm nominal loads) with a 150 ohm load. Lets say the amp offers minimal DC offset protection at that nominal impedance, and you PUMP DC into your K501, at power levels it was never designed to handle. The voice coil heats up, and cooks/melts the coil epoxy. The coil windings short, essentially bridging the speaker outputs together via a tiny wire. The mosfets in the speaker amp will briefly pump max current and will most likely melt the headphone coil wire. Theoretically (if there were heavy AWG speaker wires in the headphones) the amp would try and pass excessive current through the mosfets, and either overheat them (worst case scenario), or trip the current limiting protection.

So... I think it all boils down to how stable the amp is and what its DC offset characteristics are at a higher nominal impedance.

Someone please correct me

I have never tried this and am merely speculating, based on my past experiences in other audio related hobbies. I will delete these comments, if they are too speculative and mis-lead members from the truth.

 

[wae5]

Is there a device or simple wiring trick that could make the 150 ohm HP load acceptable to the amp and also protect the phones from frying?

 

[agile_one]

Quote:

Originally Posted by wae5 /img/forum/go_quote.gif Is there a device or simple wiring trick that could make the 150 ohm HP load acceptable to the amp and also protect the phones from frying?

Device: Antique Sound Labs UHC

DIY: Schematic for Headphones from Speaker outputs.