[Crissaegrim]

I have Grado SR 60s that I bought after researching this site a couple of years ago and I have been using and loving them ever since. I decided to try a new amp to replace a Creek OBH 11 when I lost the power supply. I bought a Gilmore Lite and used it one time to test it out. It sounded great. Later that night, I went to use it for some serious listening and upon turning it on, I heard a pop. Looked over and saw a flame and then smelled burning rubber for the next two days.

Now the left side of my headphones is very faint and the right side is perfect. What the heck did it do and is there anything I can do to fix them or send them somewhere? I’ve been on the audio merry-go-round (albeit low budget version) ever since I got into audio and the SR 60 are the first thing I have that is really giving me what I am looking for. I have the money to buy a new pair, but not upgrade.

I have since been using them with the headphone out on a vintage SAE pre-amp and sometimes I up the left channel and lower the right, but am I right in assuming that I am not getting the real sound they are suppose to make doing that?

 

[Rav]

Give Grado a call, they should be able to fix them for you.

As an aside, i never leave my headphones plugged in when i turn an amp on or off, and unplug them when not in use.

 

[vixro]

Quote:

Originally Posted by Rav /img/forum/go_quote.gif Give Grado a call, they should be able to fix them for you. As an aside, i never leave my headphones plugged in when i turn an amp on or off, and unplug them when not in use.

Great advice, as a soon to be new user of amplifiers I thank you for this insightful information.

 

[Rav]

Quote:

Originally Posted by vixro /img/forum/go_quote.gif Great advice, as a soon to be new user of amplifiers I thank you for this insightful information.

np ... Also, always turn the amp on last (after any source) and off first, that way, any surges produced won't hit the amp and get amplified.

 

[Dept_of_Alchemy]

It might be a bad idea to plug the headphone in and out of the amp while it's on, you could short the channels and on amps without protection circuits that would be a really bad thing (I believe HeadRoom recommends that you plug the headphone in before turning it on, and turn the amp off before unplugging it).

A more conventional solution for protecting the headphone is to turn the volume knob all the way down everytime you turn the amp on and off.

 

[ericj]

Quote:

Originally Posted by Dept_of_Alchemy /img/forum/go_quote.gif It might be a bad idea to plug the headphone in and out of the amp while it's on, you could short the channels and on amps without protection circuits that would be a really bad thing (I believe HeadRoom recommends that you plug the headphone in before turning it on, and turn the amp off before unplugging it). A more conventional solution for protecting the headphone is to turn the volume knob all the way down everytime you turn the amp on and off.

ummm. Not really. And on the 2nd point, you're dreaming.

The 1st bit about plugging and unplugging when the amp is turned off has to do with the intrinsic problems of the TRS style plug.

A regular headphone plug briefly shorts out the amplifier when you push it in or pull it out. Back in the 80's the germans tried to convince us to switch to a 5-pin DIN plug, but we wouldn't listen. You will occasionally see the crazy german DIN on vintage europhones.

If the output stage of the amp has no protection, there is a potential for damage to the amplifier whenever you plug in or unplug the headphones.

Most amps have a small output resistor that guarantees that the resistance between each channel and ground (or each-other) is never less than a couple ohms, and thus never a dead short.

People plug and unplug pretty quickly, so the window for damage is pretty small, and I've never actually heard of someone damaging an amp by plugging and unplugging while it's turned on. But it's theoretically possible and it's probably happened.

For the 2nd part, your advice completely ignores the real actual potential for headphone damage that some amps have at the moment of power-on or power-off.

Turning down the volume just attenuates the input on the amp. The output is still likely to misbehave if the design is prone to do so.

Amps with capacitor-coupled output, and amps that use a DC servo to zero-out DC offset typically show relatively high DC voltage on the output for anywhere from a fraction of a second to a 3 or 4 seconds after they are turned on, and often for a second or so after the power is turned off as well.

This happens because the capacitor has to charge before it starts blocking DC, and because the DC servo takes a little while to come up to speed.

DC and dynamic headphones don't get along.

If you put too much DC through the voice coil for too long, it gets hot. Potentially, the FRCH leads from the lugs to the coil itself may break just like a fuse blowing, or the heat may cause the diaphragm to deform where the coil is attached to it.

The Gilmore Lite is a discrete design with a DC servo on the output. It sounds to me like some component failed - since you say smoke and fire I'm guessing a tantalum capacitor - and the DC servo couldn't handle the resulting offset, got cooked itself, and allowed the DC offset to cook one of your headphone drivers.

Grado will repair your 'phones. And i think you should have a frank conversation with whoever built your Gilmore Lite.

Now, all that said, unless you have a high-voltage OTL vacuum tube amp, leaving your headphones plugged in just a few times when you turn on or off probably won't damage your headphones.

But if you hear a loud "Pop!" when you turn on or off the amp, it's probably a good idea to plug in the headphones at least 5 seconds after you turn on the amp, and unplug before turning off.

 

[justin w.]

Crissaegrim,

I have no idea who you are so if this is a new amp from me, please contact me about it. You can call me tonight. Send me the amp and your SR 60, I'll check out the amp and if I find a problem with it I'll send it back to you fixed and a new pair of SR 80

-Justin

 

[GlorytheWiz825]

Quote:

Originally Posted by justin w. /img/forum/go_quote.gif Crissaegrim, I have no idea who you are so if this is a new amp from me, please contact me about it. You can call me tonight. Send me the amp and your SR 60, I'll check out the amp and if I find a problem with it I'll send it back to you fixed and a new pair of SR 80 -Justin

Got to love Headfi.

 

[Crissaegrim]

Quote:

Crissaegrim, I have no idea who you are so if this is a new amp from me, please contact me about it. You can call me tonight. Send me the amp and your SR 60, I'll check out the amp and if I find a problem with it I'll send it back to you fixed and a new pair of SR 80 -Justin

UGH, I should have elaborated on the amp situation. I just wanted to start a thread about if/how I could fix my headphones. The customer service from Headamp was perfect. I was offered a bunch of options and I believe I got a full refund. It was determined to just be a bad peice.

And thanks for the advice. I emailed Grado, I'll follow up with what happens.

 

[justin w.]

You mean this already happened and I settled it? Woohoo!

Well if Grado won't take care of the headphones, I still will, so let me know how it turns out.

edit: no wonder I didn't remember, it was 15 months ago

 

[riceboy]

Quote:

Originally Posted by GlorytheWiz825 /img/forum/go_quote.gif Got to love Headfi.

No doubt. Got to love headfi.

 

[jonnywolfet]

awww how lovely, a nice happy ending.

 

[greggf]

I'm impressed!!

 

[Snacks]

Quote:

Originally Posted by riceboy /img/forum/go_quote.gif No doubt. Got to love headfi.

Justin is a class act!

MOT customer interaction/satisfaction, just one of the many beauties of head-fi!

 

[F107plus5]

Glite was always near the top of the short list for my MS2i, now it's really up at the top!

....let's face it; a manufacturer never knows when a purchased component is going to fail, but to take care of the situation so quickly and thoroughly is well beyond the call of duty. Three cheers for Justin!

!