[fiver]

 
Quote:

 
Skylab mentioned the possibility of light dimmer interferance. I wonder if this might be the case with some amp designs and not others?
 
 

 

Absolutely.  Trying to troubleshoot/fix a household electrical hum problem can get pretty complicated sometimes.  I once had a motion detector that would actually cause the panel breaker to vibrate so hard you could hear it audibly humming from 10 feet away.  It's a little unnerving to walk to your main panel and have it sound like small motor is running inside it.  Traced that to a CFL being on the same circuit, pulled the CFL and the problem stopped.
 
For light dimmer interference, make sure you are only using high quality dimmers.  This is not the time to cheap out.  Make sure that there are no florescent fixtures on the circuit (seems obvious, but people do miss it).  Two dimmers on the same circuit can cause even more problems, if you for whatever reason need two again make sure they are high quality, preferably of the same model/manufacturer and intended for this purpose. 
 
Check all grounds, everywhere.  Check all connections, everywhere.  Don''t backwire outlets.  Remove any backwired outlets and toss them in the trash.  Replace with high quality outlets and use the screw terminals. 
 
You can turn off all the breakers in your panel except for one that hopefully only has a few outlets.  Plug in your rig and nothing else into that circuit and if there is no hum, start turning on breakers one at a time until the hum appears.  In some cases it could be be due to a combination of circuits so in addition to one at a time on you can try other combinations (half on/half off, all on and turn off one at a time, etc).  Audit all devices on the offending circuit(s) and try to figure out the cause.
 
 

 

[MacedonianHero]

Quote:

I really need to do that - too bad the wife won't let me....

I find forgiveness is easier to ask for than permission.

 

[Duckman]

No noise with my old Leben or B22.
 
Too bad I can't do anything about dimmers. I'm renting.
 
I'm almost tempted to keep the Lyr in spite of the hum. It sounds great through the LCD2.
 
Quote:

Definitely.  I have had certain amps (mostly solid state, actually) that buzz due to the dimmers in my kitchen.  Many others do not.  And all I have to do is turn the dimmers OFF
 

 

 

[Skylab]

Note that I was not suggesting to remove the dimmers - just to have them OFF when you are listening

 

[kwkarth]

Quote:

Absolutely.  Trying to troubleshoot/fix a household electrical hum problem can get pretty complicated sometimes.  I once had a motion detector that would actually cause the panel breaker to vibrate so hard you could hear it audibly humming from 10 feet away.  It's a little unnerving to walk to your main panel and have it sound like small motor is running inside it.  Traced that to a CFL being on the same circuit, pulled the CFL and the problem stopped.
 
For light dimmer interference, make sure you are only using high quality dimmers.  This is not the time to cheap out.  Make sure that there are no florescent fixtures on the circuit (seems obvious, but people do miss it).  Two dimmers on the same circuit can cause even more problems, if you for whatever reason need two again make sure they are high quality, preferably of the same model/manufacturer and intended for this purpose. 
 
Check all grounds, everywhere.  Check all connections, everywhere.  Don''t backwire outlets.  Remove any backwired outlets and toss them in the trash.  Replace with high quality outlets and use the screw terminals. 
 
You can turn off all the breakers in your panel except for one that hopefully only has a few outlets.  Plug in your rig and nothing else into that circuit and if there is no hum, start turning on breakers one at a time until the hum appears.  In some cases it could be be due to a combination of circuits so in addition to one at a time on you can try other combinations (half on/half off, all on and turn off one at a time, etc).  Audit all devices on the offending circuit(s) and try to figure out the cause.

Many Head-Fi'ers are likely to have remote power control modules in their environment, such as X10 and newer light controllers.  These critters do the same damage to your power line that light dimmers do.  They're all triac or quadrac controlled PWM and put trash on the audio lines like nobody's business when they're used.  They're ok when turned off, as Sky mentioned.
 
 

 

[grokit]

Yeah illumination is overrated anyways 

 

[leesure]

Quote:

Yeah illumination is overrated anyways 

Thanks for shedding some light on that.

 

[foaming at the ears]

Duckman,
 
Are you able to hear the hum with the LCD-2, or just your more sensitive HPs?
 
Quote:

No noise with my old Leben or B22.
 
Too bad I can't do anything about dimmers. I'm renting.
 
I'm almost tempted to keep the Lyr in spite of the hum. It sounds great through the LCD2.
 


 

 

 

[Kremer930]

There is no hum with my HE6 or my AKG K702.  I tried a set of Ultimate Ears Triple Fi 10's just to see what they would do, and to confirm that the amp is usable with cans of all impedences given the worries of some head-fiers, and yes the amp does hum with my Genelex ECC88 tubes.  But it is still usable and the volume was easily controllable.  The hum was there regardless of the volume being at zero.  Once you started playing music with some volume the hum would disappear. 
 
I also just have to say that the amp or tubes definitely needed some hours under its belt.  I have found that added air and space has come after around 10-15 hours of use.  My back to back comparisons with my DV337 is showing that the top end detail advantage of the DV is disappearing and that now I almost have a Darkvoice sound but with no restrictions on peaks and some serious bass control and slam.  Loving it more and more as time goes on.
 
Cant wait for the Schiit Dacs.....  I only just held myself together for the 2 months pre-order of the Lyr.  Dont know how I will go waiting for a product that has only been hinted at so far....  I am confident that it will be worth it.
 
Quote:

Duckman,
 
Are you able to hear the hum with the LCD-2, or just your more sensitive HPs?
 


 

 

 

[Duckman]

Yeah, it's clearly there with the LCD2. Not loud, but loud enough to hear in quiet passages of music.
 
Quote:

Duckman,
 
Are you able to hear the hum with the LCD-2, or just your more sensitive HPs?
 
 

 

 

[kwkarth]

Quote:

Yeah, it's clearly there with the LCD2. Not loud, but loud enough to hear in quiet passages of music.

So you're saying that you hear hum with the stock tubes, even through the LCD-2's?
 
 

 

[Fido2]

I received my Lyr last night. Plugged her in and let her warm up. I listened with my LCD-2's. I haven't even tried my D-7000's yet. I haven't wanted to

. This Lyr is a very fine sounding amp. It puts more meat on the bones and like someone above stated it is very muscular and confident but handles delicacies with great ease and fidelity. The Lyr really brought my LCD-2's to life and man what power! I can crank this thing up til my eyes pop out

. My LCD-2's sound much thicker and richer and I notice that the treble is more forward just enough now whereas it seemed a shade receded through the Woo and Mac preamp.
 The fit and finish on this amp is first rate. Very heavy and robust feeling amp, with high quality RCA connections and smooth accurate volume control. It's just a beautiful amp. 
I hated to take off my headphones last night but I had to get to bed. More later after I try the Denon cans. So far...LOVE the Lyr! Great work Jason!

 

[roachbro]

Does anyone know how the Lyr handles with low impedance headphones like the D5000 with 25ohms?

 

[leesure]

Quote:

Does anyone know how the Lyr handles with low impedance headphones like the D5000 with 25ohms?

 
It's quoted at being able to handle impedances from 8 to 600.  It's power quote of 6w is into 32ohms, so I'd think 25 is no problem.
 

 

[USAudio]

Quote:

Does anyone know how the Lyr handles with low impedance headphones like the D5000 with 25ohms?

According to their website, they're rated for headphone impedances from 8 to 600 Ohms, so it shouldn't be a problem.
 
Also, at 25 Ohms you're looking at 8 watts RMS!