New Channel Islands headphone amp

[NightWoundsTime]

I emailed Dusty Vawter over at CIAudio.com last week for a possible audition of the VDA1 DAC for the Nashville headphone meet. He gladly obliged and also has provided a VAC1 power supply, and most excitingly a new prototype headphone amp. I received all three today.

The amp for now is in a VPC1 passive preamp enclosure, which is the same compact size and shape as the other components from channel islands. Dusty told me today on the phone that it will eventually be in the same size enclosure but a bit more customized. For now there's a Neutrik locking headphone jack, petentiometer, two inputs (currently no selector switch), and a jack for 14VAC power. It can be used with a standard wall wort or the VAC1 power supply. I'm expecting this amp to retail for somewhere around $300 when it's released. Dusty said today that the amp has a much different design than any other solid state out there now. I'll leave it to the first purchasers to open the thing up for inspection by the DIY'ers

So the real question is sound. Listening to it from my Sony with various SACD's it's got a very pleasing sound. A bit of a solid statey upper end but not as bad as I remember the PPA being. I plan on comparing it at the meet this saturday to a wide range of amps including: RA-1, PPA, X-can V2, Headroom Little, Maxed PIMETA, and the range of Emmelines as Ray is planning on coming. The basic size is slightly larger than SR-71 but there's no current battery powering so I'll have to reccommend that to Dusty. I'll be sure to try it with Senn 595's, 600/650's, SR225 and Allesandro MS1, and AKG 240S. Check the meet thread for my impressions.

 

[DevilDog]

WooHoo! Another amp to audition! This is getting better and better.

 

[NightWoundsTime]

Just got an email from Dusty with these specs, which I find very impressive:

Frequency Response: 10hz-100kHz
THD + Noise: .00014%
Signal to Noise Ratio: 120db
Slew Rate: 1300 V/µs
Dimensions: 4.40"w x 2.65"h x 4.40"d

Ok the Slew Rate is meaningless to me but those others are absolutely nuts. He said it's also capable of driving *any* headphone and they even drove some small Tannoy speakers the other day. Now I wish I had K1000's handy

 

[gsferrari]

there is a meet tomorrow?!?!?

I never knew!! Where!!! ???

I wont be there until monday but what the heck

LOL

 

[chillysalsa]

Based on those specifications, the amp is strikingly similar to the TPA6120A2 from TI.:
0.00014% THD + N
80 mW into 600 W From a ±12-V Supply
1300 V/µs Slew Rate
SNR of 120 dB
Greater than 120 dB of Dynamic Range

There have been a number of people trying this chip-based amp in a previous thread.

 

[clarke68]

Quote:

Originally Posted by NightWoundsTime ...a new prototype headphone amp...It can be used with a standard wall wort or the VAC1 power supply. I'm expecting this amp to retail for somewhere around $300 when it's released...I plan on comparing it at the meet this saturday to a wide range of amps including: RA-1, PPA, X-can V2, Headroom Little, Maxed PIMETA, and the range of Emmelines

Anybody bringing a new Gilmore Lite to the meet? The features/size/price/color seem to make it a natural competitor.

I'm a big fan of all the former Audio Alchemy guys' products...this is really exciting!

 

[NightWoundsTime]

I knew it wouldn't take long for the DIY people to identify what this thing was built on. Very interesting little chip.

AFAIK there won't be a Gilmore lite in attendance but if one shows up I'll be sure to compare. Doing the totally unfair comparison to the MPX3 shows the CI amp being pretty outclassed. I'd be pretty mad if it wasn't, as my MPX3 is upgraded to the point of costing 3-4 times more than the CI amp. Mainly what I hear are all the hi-fi sticking points, less soundstage, less upper and lower extension, less impact, and as I said before it posesses that slight upper end grain that most solid states at this price point exhibit.

Look for plenty more after tomorrow's meet.

 

[clarke68]

Quote:

Originally Posted by chillysalsa Based on those specifications, the amp is strikingly similar to the TPA6120A2 from TI.

You *know* Dusty's got a dac/headamp combo up his sleeve!

 

[agile_one]

Quote:

Originally Posted by gsferrari there is a meet tomorrow?!?!? I never knew!! Where!!! ???

It's in Nashville (aka Music City), Guru.

Our man Matthew gets around. He and DevilDog will be having all the fun this weekend. Looking at the Meet Thread it appears they've all done a terrific job of organizing, and will be having themselves a grand ol' time.

 

[elrod-tom]

I'll be interested to hear more about this. I too was a huge fan of Audio Alchemy - some of the best gear around, and a great value too.

I had an AA HA-1, and when it's properly powered (PS-II, also by AA), it was a pretty sweet amp. Class A all the way through...including some MAJOR heat issues!! I sold the amp a while ago, and there are times I've missed it. I still have a PS-II...I use it to power my MSB DAC, and it does a damn good job.

More info....and PICS!!

 

[dusty_v]

Yes, our new amp is based on the TPA6120. It's a pretty amazing part, but is very critical to the board layout and not something that most DIYers can use.
The heatsink soldered directly to the ground plane is of utmost importance for driving low impedance phones. Driving low loads IS NOT a problem with with device, we even ran a pair of 4 ohm speakers with reasonable success.
The sound from this chip is very spacious and detailed and dynamic, with an extremely low noise floor, which to me...is very important for headphone listening. We hope to have production models shipping in about 6-8 weeks.

 

[kugino]

Quote:

Originally Posted by dusty_v Yes, our new amp is based on the TPA6120. It's a pretty amazing part, but is very critical to the board layout and not something that most DIYers can use. The heatsink soldered directly to the ground plane is of utmost importance for driving low impedance phones. Driving low loads IS NOT a problem with with device, we even ran a pair of 4 ohm speakers with reasonable success. The sound from this chip is very spacious and detailed and dynamic, with an extremely low noise floor, which to me...is very important for headphone listening. We hope to have production models shipping in about 6-8 weeks.

thanks for the info, dusty. we're all looking forward to this new headphone amp and if it looks and sounds like your other products (i've had the vda1/vac1 combo) i think it'll be a winner...please post more specs and maybe even some pics as the product becomes ready to ship...

 

[Dane]

This sounds very interesting. What is the gain setting on this amp?

Quote:

Originally Posted by dusty_v Yes, our new amp is based on the TPA6120. It's a pretty amazing part, but is very critical to the board layout and not something that most DIYers can use. The heatsink soldered directly to the ground plane is of utmost importance for driving low impedance phones. Driving low loads IS NOT a problem with with device, we even ran a pair of 4 ohm speakers with reasonable success. The sound from this chip is very spacious and detailed and dynamic, with an extremely low noise floor, which to me...is very important for headphone listening. We hope to have production models shipping in about 6-8 weeks.

 

[dusty_v]

We're still experimenting with gain settings, but based on a standard CD players output of 2vRMS, a gain of 2.5V/V seems to be a good balance for most phones 30-300 ohms. I could also make it with a hi/low switch with 2V/V or 3V/V. Any input from users is most welcome, afterall...we're making this for you guys !

 

[Dane]

Well, if the amp has usable volume rotation with both low sensitivity/high impedance phones and high sensitivity/low impedance phones then you're OK. However, if max setting isn't very loud with the high imp phones or if it isn't possible to adjust to a whisper (no l/r imbalance) with the low imp phones, then there's a problem. You should try this out (sounds pretty obvious, but amazingly it appears that some designers dont actually try this). I suspect that a gain switch and/or a very high quality pot is needed for this and I also suspect that there need to be more difference between high and low gain setting. But I'm totally guessing and have little experience with this

My personal oppinion is that many amps seem to go insanely loud and that this isn't needed. For example, my HD83 tube amp only leave me with 10% usable rotation even though it's tuned to low impedance phones. This actually doesn't matter too much in that case since the pot is high quality and make adjustment easy even so.