iMac to DAC via 3.5 mini-phono jack/RCA IC?

With regards to USB DAC's; I tried a number of them over a year ago when I decided to migrate to a music server and sold my CDP (Accustic Arts CDP-1). I auditioned everything from cheap computer store types under $100, like the SilverStone EB01, to around $1K with the Benchmark DAC1, Bel Canto e.One Dac3, PS Audio DL, and on up to the Wavelength Brick and $3500 Cosecant. None of them were satisfying enough. And if a $3500 USB DAC wasn't doing it for me, then I had to try something else.

Of the USB DAC's I auditioned the Benchmark took the prize for the worst sound. It was just terrible. This surprised me given all the praise. The PS Audio was actually the most impressive for the cost in my humble opinion. Very smooth and analog-isque. The Brick excelled when I used NOS tubes, coming close to the Cosecant. The Bel Canto was defective. I tried two and the USB did not work. Perhaps the Stahl-Tek Vekian may have proven to be the ultimate solution, but then again I didn't have $12K.

I went some months, off and on, w/o a source. Sooloos, like the Vekian, was way too expensive for a music server (a high-end computer that will be obsolete in 6 months). Another one, Resolution Audio, only sold as a whole system. Then I tried the Squeezebox3 (digital output only, of course). This was much better then the USB DAC's. But it had constant drop-out issues. That turned me off wireless. So there just wasn't a complete, reliable, and affordable solution that I liked. This is what happens when you get into the 'high' of high-end audio with tube based gear and horn speakers. The bar is set too high. But at least my source can never out perform the rest of the system. I'll hear everything.

My system has changed since, but the iTransport via a Stealth Varidig digital IC w/ custom RCA's to a Reimyo DAP-777 has proven to be the most satisfying digital I have heard from my system in 18 years. I even tried a couple reputable USB/SPDIF converters. Aaack!! Atrocious.

I've been at this computer setup for over a year now. First with a Musiland MD10, then a new Benchmark DAC1 (kept for 10 months), then a Bel Canto DAC3 (kept for a week) and now a MHDT Havana for a month. The Havana wins out. The Bel Canto was p#ss poor as far as USB implementation. I wish I still had the DAC1 to compare now that I resolved the power problems I've been plagued with, as it was incredibly bright but I think with the right setup it may work out alright.

Source is an IMac 20 feeding an Empirical Audio Turbo-3 via USB, then digital coax to the DAC, then to a Rogue tube amp (Itunes providing the volume attenuation, which contrary to popular opinion works perfectly in my setup). Just as long as your girlfriend, wife or kids (or all three) don't click on any website that produces video playback automatically, otherwise the speakers would be toast.

One crucial (absolutely crucial) lesson in all of this for me is the power noise the computer throws off. If you don't deal with it, it will impart a lot of harshness/sibilance, regardless if the DAC or whatever conversion device you use says it isolates power and deal with jitter (i.e. Bel Canto, Benchmark or Empirical). The IMac is just as susceptible to power problems as a CD player or DAC (moreso given it's design intent, which definintely isn't as a music server).

Digital power cords work wonderfully on the computer and obviously the DAC, as I was just about to throw in the towel with my setup until I got a hold of a couple to try. Siblance is all but reduced and etch is nearly eliminated. And that's with using silver ICs which to this point I never had much luck with.

Sorry for the winded message and it's always YMMV.

'Bright' is an accurate description of how I would describe the Benchmark USB DAC1. So bright in fact that I analogized it as; "the walls of my ears were being stripped, like solvents to paint". It was simply a case of being outclassed by the rest of my system, as were the other USB DAC's. I could hear their limitations, like bad digital transfers viewed on a 1080p plasma.

I used a high-end silver power cord with my iMac, plugged into a Walker VelocitorS. I like to keep my system simple. Shortest path possible. Avoiding all the extra cables and devices and power cords....

I've tried several times running the IMac into my Hydra-6. Everytime I do i get an improvement in dynamics. blacker background, blah blah blah, but it always tilts the upper frequencies too much. Regardless of powercords on the IMac or Hydra, the amp I'm using, ICs on the DAC, etc. At least I've convinced myself I'm not full of sh#t or hearing things, because it's definitely a constant.

i had the same opinion about the benchmark dac. stereophile loves it because they probably get $$$$$ for advertisements. there are many other dacs out there that are much better. i liked my old cal audio sigma II tube dac better and that was $200.

for my music server system, i isolate the computer from the music by using the airport express units. i also have hooked up my mac mini and now a 24" imac using optical cables to jitter devices. using optical cables, you isolate any computer noise that would be possible to transfer thru copper.

i also have played with the sooloos system. what a waste of $$$ IMO. you get a decent interface and thats about it. my iphone remote app does a better job at presenting music anywhere in my house than the sooloos does. and when you cost out the sooloos system with the appropriate setup to make it fault tolerant (raid setup), able to perform backups, whole house server, terabytes worth of storage, you are approaching $20k+ and it contains a terrible dac (that might be updated by now). again, IMO.