Any opinions on the AMR Digital Processor 777 Dac?

Correction: "shielded"

Hi Audiofun, would you care to share your insights on your DIY ICs? And to which known brands IC have you compared them? Anychance of making your own magnetic cables? I have the HFC CT1-E throughout my system and love to have a CT1-U comparable cabling.

Back to the SE upgrade, none has one yet?

On audiofun's endorsements, I ordered the iTube, got it today and will evaluate it more for a couple of weeks.

Between my NAD M51 and ATC P1 power amp, these are my initial findings: after level-matching from going balanced to single-ended, I do feel some transparency is lost with the iTube as a straight buffer with no gain (so am glad to confirm the M51 preamp is doing a good job). This is also the case/worse when using it as a preamp with gain.

The "digital antidote" feature is subtle. It mildly softens/rubs out the sharpest leading edges of treble notes, like layering in a low-powered unsharp-mask filter in Photoshop. Tried this on some songs that have clear peaks but the M51 doesn't need this affect as it's not screechy-sounding in the first place, and honestly, where sections of music do have piercing notes, they should be reflected accordingly! If your gear is sounding annoyingly peaky all the time, then maybe something else needs fixing rather than attenuating transients.

The last feature - the 3D HolographicSound - works as described and is novel/fun to play around with, in both "normal" and "desktop" mode. I need to listen to less electronic music to get a full take on it.

Don't get me wrong, I am NOT an accuracy above musicality freak at all. I do favor naturalness and fidelity.

Guess I'd put it like this, when we're all following the same JRiver setup guides, turning off all DSP and playback options, and eschewing treble or bass controls in our pre-amps...but ignoring say room acoustic treatments which are much more dramatic, what are we doing?!

My summary of the iTube is that it's really only suited for single-ended DACs with pre-amp sections that are bad in all the areas it addresses!

Hi JazzOnTheHudson, some comparisons have been to Murray James, FIM Gold, Argento (CRAZY EXPESNIVE!!!!) and I always go back to my design. Not sure exactly what you are referring to by "Magnetic Cables". DIY cables can be as good and better than aftermarket if you know what you are doing and start out with superior materials. Do not fall for the Continuous Cast marketing non-sense. I am not going to get into that except to say do some googling and find out what and why that inferior form or wire manufacturing was created. Leave it to the cabling liars (oops sorry marketers) to completely obfuscate the truth.

Loftarasa; I will state that my experience with the iTube is completely to opposite of yours. I find the 3D Holograhic indispensable and absolutley transpatent in zero gain mode. Again, it bettered both my MFA Reference and Baby Reference and Equaled "No Preamp" (i.e. using PureMusics 64 bit volume control in conjunction with a wide dynamix range 24/176.4khz recording and -6dB on PM) as far as transparency. I can't speak for your system but the iTube is ABSOLUTELY transparent over here. Listening to Enya via my SP10-MK3/AMR PH77/AMR dP777 and iTube and i defy anyone to hear a loss of detail when the iTube is installed (if it were out of my system which it never is :).

I have never needed to use the digital antidote with the AMR.

One thing to note, the wall wart IS orientation sensitve, the cord leading from the wall wart should be aligned with the ground plug receptacle on your wall socket. This is easily heard if it is in the wrong configuration.

I have found this to be the case with all of my amplifiers Reimyo PAT777, Graaf Modena, both Graaf GM 200's, Acoustic Reality Thaumaturges and the EAR 1001 REFS and my own 230 watt monos.

The MFA Reference units are some of the finest volume attenuators out there, the Concert Fidelity Pre is world class and I still went with the iTube. I know nothing of NADs gear having never purchased it, perhaps it is simply not sympatico.

YMMV

@audiofun, your gear is higher-end than mine and I don't doubt your claims about the iTube's performance in your system.

But I'm sending my iTube back as it's not adding enough value for me. Having to go from variable balanced to fixed output single-ended may be a factor in my evaluation (different output stages, different cabling, voltage levels, SNR, CMMR things), though.

Fiddling with the wallwart connector thing sounds bizarre; not quite what you're onto there.

My last comment is I know iFi are coming out with the iTube mini, where we should expect higher performance (for higher outlay). That in itself may also suggest the iTube's most obvious use-case is computer/desktop/second-systems. I'd be interested in that if it supports balanced inputs/outputs and/or I switched to a fixed output DAC.

Cheers.