Stan's New Dac - any reviews yet?

[Labarum]

As philosophy, garbage in/garbage out sounds great.

Of course it is true that detail once lost cannot be recovered, but . . .

[NRG]

As philosophy, garbage in/garbage out sounds great. I just don't think it works that way in practice. To my ears, at least, the differences between DACs, even in radically different price ranges, are subtle nuances compared to the obvious differences between speakers, often even speakers of very similar design.

Tim

Indeed, the purveyor of this philosophy was trying to sell a turntable at the time.

I don't agree about DAC's, my tweaking of the 7510 has proven to me there is a lot of scope for changing the sound presentation and quality...and not in a small way either, the differences are very noticeable.

[tfarney]

Indeed, the purveyor of this philosophy was trying to sell a turntable at the time.

I don't agree about DAC's, my tweaking of the 7510 has proven to me there is a lot of scope for changing the sound presentation and quality...and not in a small way either, the differences are very noticeable.

And I don't doubt your experience. It's all relative I suppose. You get a very noticeable difference from a DAC tweak. But a change from horns to ribbons? From floor standers to mini monitors? From passive to active? A dramatic transformation.

Tim

[Labarum]

Indeed, the purveyor of this philosophy was trying to sell a turntable at the time.

So he was, but it wasn't all sales hype. The LP12 did represent a leap forward with technology. The idea was to get as clean an output from the vinyl as possible, pass through a transparent amp onto a small speaker that traded mid range clarity and low colouration against bass extension . CD came along and clarity could be had by all without the precision engineering overheads. The trouble with CD players was the amps they drove. They couldn't handle the dynamics; and, to be fair, the digital mush that early post digital filters didn't catch. It was a similar problemto putting a Ford Anglia onto the newly opened M1. (For those outside the UK when the first six lane highway was opened ordinary production cars blew up because they could not handle the sustained speed of 70mph!)

I did some listening to the LP12 at the time - there was a turntable and arm that had an oil dash pot that extended in an arc across the LP - a paddle on the end of the cartridge dipped into this dashpot - at audio frequencies the arm was effective locked solid at both ends resulting, I thought, in a sound with much snappier transients and firmer bass.

All of this precision engineering was expensive - chips are not. Stan gives us the chips in a case that is domestically acceptable but not expensively engineered. Great! *AVI has worked out that if they can hide the chips in the wooden boxes needed for the speeakers thay can sve themselves and the customer some money. I guess, though, they have kept the greater part of the savings for themselves.

* http://www.avihifi.co.uk/

[kbuech]

And I don't doubt your experience. It's all relative I suppose. You get a very noticeable difference from a DAC tweak. But a change from horns to ribbons? From floor standers to mini monitors? From passive to active? A dramatic transformation.

Tim

A transformation in rhythm, pace, emotional connection with the listener, musicality? Not in my experience. Those have been determined way earlier in the chain, I think at the source. Linn had it right with the LP12, I could easily demonstrate a marked improvement in Hi-Fi when I sold these in the 1980s. And Stan Beresford and others can demo this vast improvement with their "front-ends", DACs. IMHO of course.

[Labarum]

Stan,

Just seen your webpage on the 7520. Three comments.

1. I am not sure too many people will know what "SB3" is. Perhaps it should be expanded to "Squeezebox Classic or Duet".

2. Some of your headings are in blue and underlined. This suggests they are clickable, and they are not.

3. These words are unclear to me:

"Separate Left and Right audio ICs are behind the audio capabilities of the TC-7520 headphone amplifier. This is only used for the headphone amplifier output. Audio to the external headphone and line outputs is not processed this way, only level control is adjustable in the digital domain for these ports."

"This"? What? The separate left and right ICs?
"Audio to the external headphone and line outputs is not processed this way . . . " Which way? Not through the separate R and L ICs, is what the English seems to mean, but it can't be what you mean. Is the volume control for variable line out and the HP amp digital?

---

Glad you're keeping busy and sold out!

[leo]

Some dac chips allow the gain to be controlled digitally within the dac chip, IC's usually mean integrated circuits like op-amps so maybe the actual gain/vol is adjusted using the dac chip and the IC's are used as drivers for the headphone out

Its sort of hard to explain

[ReachtheSky]

Stan's updated webpage on the 7520 does look interesting.

Regarding USB dac's, is it standard for USB input to only support up to 32, 44.1, and 48khz sample rates and for max word lengh of 16bit? How does that compare sonically with 96/24 input from SPIF? Maybe Stan's separate USB reclocking compensates for all that?

The description of the headphone amp output and the variable line out (preamp out) confused me. Are they effectively one and the same as initial reports suggest both to be very good?

Looking good Stan.

[tfarney]

A transformation in rhythm, pace, emotional connection with the listener, musicality? Not in my experience. Those have been determined way earlier in the chain, I think at the source. Linn had it right with the LP12, I could easily demonstrate a marked improvement in Hi-Fi when I sold these in the 1980s. And Stan Beresford and others can demo this vast improvement with their "front-ends", DACs. IMHO of course.

MHO differs, I suppose. I don't particularly believe in PRaT, or the musicality of kit. Transformations in rhythm, pace and emotional connection with the listener are, in my view, the territory of musicians, not chips and valves, so I look for electronics that are as transparent as possible, and transducers that please my ears.

YMMV.

Tim

[StanleyB]

Stan's updated webpage on the 7520 does look interesting.

Regarding USB dac's, is it standard for USB input to only support up to 32, 44.1, and 48khz sample rates and for max word lengh of 16bit? How does that compare sonically with 96/24 input from SPIF? Maybe Stan's separate USB reclocking compensates for all that?

The chip I use only supports 16bit. If you play back a CD via your PC the output from USB or SPDIF to the DAC would both be in 16bit/44.1kHz.

The description of the headphone amp output and the variable line out (preamp out) confused me. Are they effectively one and the same as initial reports suggest both to be very good?

The headphone amp and line output are two different circuits. Just like in a preamp or integrated amp, when you plug in or unplug the headphone, you switch between output circuit or headphone circuit.