[Andrea]

I just really enjoyed the Go-Vibe with John Mellencamp, The Lonesome Jubilee. The 24V thing has transformed it... It'll be interesting to keep listening to this amp for a few days, and then go back to the Xenos. By then I should be able to decide which is better for me & in optimal working conditions.

 

[DDF]

Quote:

Originally Posted by gtp Thanks for the interesting results. Can you please explain the above statement a bit. Does that mean that for this amp, 24V is effectively the same as 9V in "driving" even high-Z headphones?

No, not the same, 8.5 dB less headroom at 9V that 24V. Still, it played quite loud with my DT770s (600 ohms) at 9V, I get the impression the implementation is pretty close rail/rail.

Compariuson was more to show no increase in distortion or noise at the lower voltage, meaning the part is adequately biased/set up even at teh lower voltage.

PS crosstalk is the signal from left that leaks to right and vice versa.

 

[DDF]

Quote:

Originally Posted by Andrea DDF, your sound card doesn't look entirely adequate fo measuring today's high performance headphone amps... The datasheet actually tells a very interesting story as regads the LM6171/2's harmonic distortion. It says -110 dB (2nd harmonic) and -105 dB (3rd harmonic) at 1 MHz (!) while sourcing a respectable amount of current onto a 100 ohm load. (Note that such specs result from these chips being op-amps conceived for video applications, not audio) It's not surprising, then, that the amp's performance is beyond the measuring capabilities of your consumer sound card. If only it all translated into the kind of natural sound I like... (or in a exceptional transparency/resolution at least, in the absence of the other ingredient of the cake, i.e. the sheer natural beauty)

Andrea,
Only so much one can do with alowly Audigy 2Zs (it's no Audio Precision!) but you see the noise floor is way down in the -120 region when its run 24/96. Good enough for what I wanted to show.

About 10 years ago I built a small preamp based on the LM617x. Total fluke, before anyone was using it. My work used to involve quite a bit of high speed telecom and these were being used as line drivers, so I gave it a shot as we had some lying about. I found it susceptible to RF, the layout had to be really on the money. You don't see *any* evidence of a capacitive roll off even up to 45kHz. The low pass must be in the 100s of kHz. Good or bad depending on your philosophy! I'd like to put it on a scope and see if there's any ultrasonic making its way through.

I really like the way it sounds with the Sony's around the house, but its a bit ruthless with the Beyers. I plan on experimenting more with my main system to see if I can tell if its mostly the Beyers or the GV5.

 

[DDF]

Quote:

Originally Posted by Andrea I'm starting to really like what I hear. No, it doesn't exactly challenge my modified Xenos for refinement & beauty of timbre, but it has its own fascination. For now it'll stay where it is...

Absolutely, this handsomely rewards burn-in (a must).

 

[Andrea]

Quote:

Originally Posted by DDF Absolutely, this handsomely rewards burn-in (a must).

Oh, yep. (and high voltage power supply too

)


I had slided towards scepticism about headphone amp burn in lately, oh well...

 

[Andrea]

For criticising the Go-Vibe through this thread.


Now, I'm eventually appreciating the Go-Vibe for how it's meant to sound.

I just listened to Tom Waits, Blood Money once again, and the Go-Vibe rendered all the subtleties in Tom's voice, piano notes & trumpet, & all those background crackling sounds very beautifully. I noticed that tonality is starting to become complex and satisfying, as well.


It looks like I'm becoming a Go-Vibe convert!

 

[dw6928]

does the 9v battery need to be removed when running on the Elpac. I am guessing no but thought I'd check. My microamp has 2 settings for battery and external and the go vibe only has the knob/on setting. also burn in times?

 

[odmanca]

Quote:

Originally Posted by dw6928 does the 9v battery need to be removed when running on the Elpac. I am guessing no but thought I'd check. My microamp has 2 settings for battery and external and the go vibe only has the knob/on setting. also burn in times?

From Norm's web site:
PLEASE NOTE: THERE IS NO BUILT- IN BATTERY CHARGER ON THE GO-VIBE, SO YOU CAN LEAVE THE BATTERY IN PLACE WHEN USING AN EXTERNAL DC POWER SUPPLY.

http://www.go-vibe-headphoneamp.com/...formation.html

 

[odmanca]

Quote:

Originally Posted by Andrea For criticising the Go-Vibe through this thread. Now, I'm eventually appreciating the Go-Vibe for how it's meant to sound. I just listened to Tom Waits, Blood Money once again, and the Go-Vibe rendered all the subtleties in Tom's voice, piano notes & trumpet, & all those background crackling sounds very beautifully. I noticed that tonality is starting to become complex and satisfying, as well. It looks like I'm becoming a Go-Vibe convert!

Andrea,

Thanks for reporting back, based on your observations I think I will order the Elpac 24v.

I have an Elpac 12v adapter and I did ask Norm whether it's necessary to get the 24v Elpac. Norm's reply indicates that the difference will be noticeable but the 24v is not a must, 12v should work just fine. However from your experience it seems the difference is big enough to justify spending the extra bucks. Thanks again.

 

[izquierdaste]

My new amp arrived last night as well. I am a really happy camper at the office right now. I only have it hooked up to a Phillips Aurilium and my trusty koss a130s at the moment, but I really feel involved with the music. There is a noticeable improvement from my old pa2v2. I feel engulfed by music from sufjan stevens and mogwai. June of 44 has the ideal amount of instrument separation to hear each band member individually and as a whole at the same time.

I had bought a 24v elpac NOS from ebay for $12 delivered. I emailed the guy today and he didn't have any left. However, I told him to email me if he gets anymore in stock and I could perhaps send some customers his way.

Enjoy my friends

 

[odmanca]

Quote:

Originally Posted by izquierdaste My new amp arrived last night as well. I am a really happy camper at the office right now. I only have it hooked up to a Phillips Aurilium and my trusty koss a130s at the moment, but I really feel involved with the music. There is a noticeable improvement from my old pa2v2. I feel engulfed by music from sufjan stevens and mogwai. June of 44 has the ideal amount of instrument separation to hear each band member individually and as a whole at the same time. I had bought a 24v elpac NOS from ebay for $12 delivered. I emailed the guy today and he didn't have any left. However, I told him to email me if he gets anymore in stock and I could perhaps send some customers his way. Enjoy my friends

$12! That's a steal, thanks.

 

[spikyho]

My v5 arrived yesterday in Oakland, CA after its shipping on Aug. 23. The border crossing seems to be returning to normal/QUOTE]

That's awesome news for me. My amp was shipped out on the 24th and I'm waiting for it to get to me here in sonoma county (bout an hr away from the bay). Originally I thought it was gonna take two weeks because it seems like btbill's amp still hasn't been delivered and he's in So. Cal. Now I'm hoping that the amp will make it over here in the next few days.

 

[btbill]

Got mine today, right out of the box, using the recommended 9v rechargable, well lets just say that I am pleasntly surprised. Customs must have been doing a burn in for me. Can't wait to spend some more time with this amp!!
THE WAIT WAS WORTH IT !!!
btbill ( still a new guy )
Anyone wanna loan me some 701's????

 

[dw6928]

anyone run 701s with their new GV5 and an Ipod? I seem to have to turn the volume knob to about 2:00.

 

[TR909]

sigh. still vibeless here in nyc. ordered on the 16th and figured it would be here today as other nycers who ordered around the same time got theirs this week. why oh why did I not know about the fedex option??

Dear Mr. Customs Man,

Please send my amp at my earliest convenience, which is now. In return you may have my PINT amp which looks far more like a small rudimentary explosive device for you to "inspect".

Cheers,
Mr. Unabomber