Originally Posted by bleudeciel16
I think I might swap the cables on the HD650, with the main reason being to get rid of the dangerously long cable. (the long cable was the reason my HD595's died, I tripped on the cable so many times, causing the headphones to fly off the desk and slam onto the floor)
I have a large playlist of FLAC music on repeat. I started it last night so I'll stop it when I get home and call it good. I suppose I could just leave the Lyr on for a whole week to let the tubes get nice and settled.
Ouch. Yeah, not snagging it is probably the best argument for recabling, ever
Oh don't think there's a need to leave the Lyr on for that long to do it. Honestly, I wouldn't often leave a tube amp on unattended anyway. (don't panic for today, initial burn-in and all that), and we're talking about small signal tubes, not the big power tubes. Big power tubes can light up real nice in a spectacular failure. Mixtures of ozone and mercury are rather unpleasant. Small signal tubes generally won't ever do that, though the bottle can crack in very spectacular rare events. Still, safety first. Never leave it on unattended, or if you do so do it sparingly when you know you won't be too far from home. And I'd never leave it on overnight. Will it erupt into spectacular flame? Extremely unlikely. But it's good to be sure Melted HD650s aren't pleasant. Neither is being immolated alive. But most importantly think of the 650s....
Yeah, people DO do it. But people do lots of stuff. And there's no real need to. Just enjoy the sonic change as the tubes burn in, and leave them on while you're doing things around home if you want to speed up the burn-in. Weekends I often leave them on during the day until the end of the night, but not if I go out. Kind of like halogen lights.
Originally Posted by Tilpo
They got blown? How did that happen?
And could you give a source on the burn-in measurement of the HD650? Seems like and interesting read.
Oh it was back at the beginning of April. I had a thread on that asking for suggestions for upgrades. Ended up with HE-400 after being talked out of HE-500 and into HE-400 by some pros who's opinions I really respect and also ended up with D5k as a compliment as a result. Then missed my HD650s, ordered new drivers, and splurged on a silver cable to treat myself for their loss I learned in the process how beautifully modular and removable every square inch of the HD650 is.
It happened due to a defective Lyr. I have two Lyrs, both from the same batch, only one is defective. One other Head-Fier lost HD-650s to a Lyr from the same batch with the same symptoms. There was a third head-fier with similar symptoms who hasn't, as far as I know, had real damage from it yet. I advised him with Jason's blessing to send it back, but I don't believe he has yet either. The symptoms are obvious, but I misinterpereted them. Used it for months with the symptoms without flaw. It's unrelated to power-on thump at all, however the day I blew the drivers I plugged the headphones in before the relay closed, and the combination of the "pop" I get as a result of the defect each time I plug in (no matter when I plug in) plus the normal thump of the relay closing pushed it over the edge, and I believe separated the voice coils on both drivers (severe rattling, loss of all bass response on the left side, etc, etc. No physical tear on the diaphragm.) Left more severely than right, but both bad enough. The pop was loud enough from 4 feet away.
I don't know the exact nature of the defect yet, and neither does Schiit because the other person it happened to is in the UK and didn't send it back, and I've been dragging my feet, still using the amp. I'll probably send it in shortly. I keep my old set of damaged 650 drivers tethered dangling from the stock cable and plug that in after the relay clicks to "pop" the bad charge out of it. After that I can plug and unplug however much I want without issue. Something is storing a charge after powerup and holding onto it until a load is connected. I suspect a bad capacitor, it could be a bad/malformed trace to ground from the relay or something too.
It's a very specific defect, not the nature of the Lyr itself (I always have to qualify it because any time I mention this people jump and say "yeah I've heard those Lyrs are dangerous.", referring to the power thump issues from before they had relays. This has nothing at all to do with power on thump, it happens the first plug in after power-on even if it's 30 min later. Different tubes seem to reduce the effect of it as well, and every now and again it doesn't do it at all.)
I suspect the surge is just under the damage threshold and had I not plugged in before the relay snapped to combine the normal sound with the already-near-the-limits defect pop, I'd still be plugging in daily none the wiser of the danger.
Regarding the measured HD650 burn-in, it's from the king of measurements who is a prominent former head-fi-er who we can't name who happened to design an excellent DIY amp and DAC. He reviewed HD650 (finally) sometime in the past year or two and mentioned with the usual eye-roll the burn-in factor and did mention that he did actually measure very slight effects from burn-in as included in his charts. He made no comment as to if he felt the sound AUDIBLY changed or not, but he did confirm that a burn-in effect, even a minor one, is a measurable effect. I'm sure you can find it easily enough
Originally Posted by bleudeciel16
The "B" word scares me. I wish there was a way to limit the output of the Lyr without messing with the sound. I keep imaging somehow cooking my 650's on accident. I'll be careful with the volume knob so it shouldn't be an issue but it still worries me in the back of my mind.
Heh, I really wouldn't worry about it if you don't have specific symptoms that I had, which is, the first time I plug in after power on there was a large "pop" or "snap" sound coming from the HD650s, even if I plug in long after the relay closes. Jason assured me that a small "ping" sound would be normal when plugging in but wouldn't be audible if the headphones aren't on your head. This sound could be heard from 3 feet away most of the time with the headphones on the stand and is positively not a normal thing to hear. Both of us with blown 650s had the same symptoms (and the symptoms, for reference also manifested on K702...it's not an HD650 or impedance thing...)
Of course the volume knob...yeah if you turn the volume knob up too far on Lyr, or any powerful amp including AV receivers sure you can blow headphones. But always remember that any sound capable of burning your headphone drivers is likely to burn your EARDRUMS first if they're on your head. I was fortunate with my incident that they were NOT on my head. Lyr's no more dangerous than any big amp with regard to user error
Originally Posted by daigo
I got tired of the long HD650 cable as well and built a shorter 5' long cable for it to use at my desk. Makes for less clutter and risk of rolling over the cable with my chair. The other option is to coil up a portion of the cable near the plug and have that sit on your desk to shorten it.
Yeah, I broke my Cardas 650 cable by rolling it over one too many times with the char, however the length and the durability for being rolled over with a chair were the main reasons I bought it It survived years of that abuse. But I love my 5' cable now. 6' may have been a hair better, but 5 is pretty good.
I coil my long HE-400 cable and keep my AD700 cable in a permanent coil. But it's still a pain to deal with.
Originally Posted by MickeyVee
I just mounted a classy aged brass coat hook on the wall beside my desk and wrap the cables around it. For $3 at Home Depot, its a cheap and elegant fix.
Not a bad idea. Very studio-chic. Though it would almost benefit from a 15-20ft cable for that sort of winding. A 10-footer would be too short for that for me.
Edited by IEMCrazy - 6/8/12 at 10:30am