[chadh]

Dusty,

I've recently procured a VHP-1 and VAC-1, and am enjoying them a great deal!  Thanks.

Currently they are hooked up to a Squeezebox 2, and I'm listening through a pair of AKG K501 headphones.  These headphones are relatively insensitive (I think around 94db), and I need to turn the VHP-1 volume up quite high (when the SB2 volume is maximised and the VHP-1 is set to the high gain setting): often as high as 3 or 4 o'clock.  This arrangement is fine.  But...

I'm planning on having my SB2 modified, and one of the mods would lower the output of the SB2 from around 2v to around 1v.  So now I'm worried that the VHP-1 won't drive the AKG 501s to my desired volume once the squeezebox is modified.  Do you have any sense of whether I should have much of a problem?

The set up currently has the SB2 passing directly to the VHP-1, and then the loop out takes the signal to my VMB-1s.  But I'm planning on adding a tube pre-amp to my system.  In that case, I'd have the SB2 feeding the pre-amp and the pre-amp passing the signal to the VMB-1s (via pre-out) and had planned to have the VHP-1 fed through the tape out on the pre-amp.  As this pre-amp will be customised, I could change the tape-out to a second pre-out.  That would give me some extra amplification before the VHP-1.  Does this sound like a worthwhile option?

Chad

[CIAudio]

Sounds like the mod to the SB2 removes the gain stage and takes the signal straight off of the DAC. To some this sounds like a good idea, but if you have to add another gain stage somewhere else, it defeats the purpose unless the added gain stage is much better than the existing one.

The tube pre-out should give you plenty of gain and a different sonic signature...just depends on what you like.

[Meshbro]

I was surprised to see that you have to push the VHP-1 gain so high to
get a decent volume out of your system.  I have the VHP-1/VAC-1 team,
AKG 501s and a Squeezebox3.  (The SB2 and SB3 are said to be almost
identical save for their enclosures.)  It's not my usual setup, but I
put them together to see if I had a problem similar to yours.  I
didn't.

In fact, it's a good thing that I wasn't wearing the headphones when I
first hit play on the SB3; the sound came blasting out of the 501s,
audible from a couple of feet away.  (I normally use the SB3 as one of
several digital sources, so I had had its volume set to maximum.)  I
listened to several tracks (lossless files ripped from my collection
using the Linux flac utility) of a variety of genres.  With the SB3 at
maximum volume, I had to use the VHP-1 on the low gain setting and
with the volume knob at just above minimum for comfortable listening.
With the SB3 volume set at 20 of 40, I turned the VHP-1 knob to the 12
o'clock position.  I had to set the SB3 volume to 5 of 40 to get to
the point where I needed to use the high gain setting and turn the
volume knob to about 3 o'clock.  Of course, there will be ear to ear
variation, but my experience with this equipment indicates that there
is more than enough gain available, probably enough to go to very
uncomfortable, even harmful, volumes.

I hope that this information is helpful.  Good Luck.


Hardware details:

   AKG K501 Headphones
   VHP-1/VAC-1 Headphone Amp
   AudioQuest G-Snake Interconnects
   Squeezebox3
   SlimServer Version: 6.2.1 running on a Debian Linux system

Music used for the testing:

   "Sapphire Sky Blue" from Keystone by Dave Douglas
   "Blood Makes Noise" from 99.9 F degrees by Suzanne Vega
   "Paradiesseits" from Perpetuum Mobile by Einstuerzende Neubauten
   Beethoven's Sonata for cello & piano No.2 in G minor (a recent ECM recording)
   "Some Velvet Morning" from Songs We Should Have Written by Firewater
   "Back In Control" from After the Devastation by Leaether Strip

[chadh]

Dusty,

Thanks.  Primarily, I like to listen through speakers.  So the mods to the squeezebox make sense on that level.  It's just an issue of how best to cope with the lower output from the squeezebox on the ocassions I need to use headphones.

I guess I was really wondering whether you had a sense for whether the VAC-1/VHP-1 combination should really be stretched in playing at reasonable listening volumes for headphones like the K501s if the source is a little less powerful than typically encountered.

Thanks also to Meshbro.  It seems like we have very different experiences with volume levels (as I really don't think I like to listen ridiculously loudly).  I'll have to go and check that everything is set up properly.  I have:

SB2 (I'm not sure which version of slimserver I have...but I haven't played around with the versions and their different volume controls) with a Hosfelt linear power supply -> Bolder m-80 interconnects (0.5m) -> VHP-1 (powererd through the VAC-1, with Bolder nitro power cord and the stock umbilical) -> AKG K501s.  

The files are all EAC generated FLAC files.  I have to admit, I can't remember what I was listening to the other night:  Sting's "..Nothing Like The Sun" and "The Soul Cages" and maybe Chick Corea's "Akoustic Band."

The K501s are pretty new: they probably only have about ten hours on them.  But I'd be surprised if break-in would make much difference to how loudly they play.

Maybe I have something on my PC set incorrectly, so that the volume is muted.  I'll have to play detective. Thanks.

Chad