[euclid]

i would think the volume pot has to be over that 9:00-10:00 hump because there are tracking problems below that. you can change internal jumpers to set attenuation of the XLR outputs so you can have enough headroom to use the variable setting on the DAC1. other than that limitation it should be linear response no matter how far up the volume on the DAC1 is set.

 

[infinitesymphony]

Quote:

Originally Posted by euclid /img/forum/go_quote.gif i would think the volume pot has to be over that 9:00-10:00 hump because there are tracking problems below that.

Is this true for both the continuous and detented volume knobs?

 

[EliasGwinn]

Quote:

Originally Posted by tubaman /img/forum/go_quote.gif Hi Elias, thanks for the reply. I am using RCA outputs now. What do you mean by "the appropriate signal level" (to be achieved by the volume control)? How do I know when it's appropriate? (E.g. minimum of ___ detents)

If you can find out what the input sensitivity (max input before clip) on your (pre)amp is, I'll let you know where to set the volume control.

The RCA outputs are configured to the -10 dBu standard level, which is common to most RCA outputs on consumer devices. So, it should be ok as it is. However, if there are gross inconsistencies between the volume of the DAC1 vs. other components, you can use the front panel volume control for accommodating.

You could also re-calibrate the analog outputs using the calibration trim-pots in the rear, but this requires using a test tone and a measuring device such as a multimeter. There is info in the manual about this type of procedure, and I could answer any additional questions.

Thanks,
Elias

 

[olivier]

Quote:

Originally Posted by EliasGwinn /img/forum/go_quote.gif Olivier, The distortion does not increase with higher output levels with the DAC1. The DAC1 is designed to operate completely in its linear region at all output levels. In fact, if your amp was able to accept +29dBu input (most can't), it would be advantageous to keep the DAC1's output level as high as possible to obtain optimal signal-to-noise ratio.

Elias,

Thank you so much for your answers so much to the point. I am sure that your contributions are much appreciated by all readers of this forum. I am now quite convinced that the benchmark is the way to go for me, the quality of the support has completed the job of my online research.

I am thus going to save on a preamp, and pair the benchmark with an amp tube (probably CJ LP70S). My idea is that the tube amp may add some smoothness to the rather analytical DAC. I'll let everyone here know how that's doing!

Thanks again, cheers,

Olivier

 

[poo]

Quote:

Originally Posted by olivier /img/forum/go_quote.gif Elias... I am sure that your contributions are much appreciated by all readers of this forum. I am now quite convinced that the benchmark is the way to go for me, the quality of the support has completed the job of my online research.

x2

 

[riverlethe]

Wow, looking at the specs and reviews on this thing... Extremely low distortion, ample power and a flat frequency response. I don't expect Elias to comment, for obvious reasons, and I don't want to turn this into a flame-fest, but what more could one possibly need that couldn't be accomplished with a computer (adding nothing to the analog signal chain) EQ or DSP of some kind?
I hypothesize that all this "soundstage" talk with different amps and tubes, etc., is simply a matter of frequency-response manipulation with varying psychoacoustic effects.
I'm not an electrical engineer or even an experienced audiophile, and I may very well be wrong, so feel free to ignore me.

 

[poo]

Quote:

Originally Posted by riverlethe /img/forum/go_quote.gif I hypothesize that all this "soundstage" talk with different amps and tubes, etc., is simply a matter of frequency-response manipulation with varying psychoacoustic effects. I'm not an electrical engineer or even an experienced audiophile, and I may very well be wrong, so feel free to ignore me.

I agree that it is probably the case from time to time, but in this particular thread, there is very little talk of acoustic impressions. Most of the information presented on these pages is fact and figures based. I don't own a DAC1 yet, but do plan to buy one based on my research - which has taken a few months.

If you are serious about answering your queries, read through the 50 odd pages here as a good start to understanding the thinking and development behind the DAC1. I'm not saying it will disprove what you are questioning, but it will present you with some of the slightly different techniques used by the engineers involved in developing the product, which I believe make all the difference (such as the way audio is 'reclocked' internally).

The only way to test the validity of any product is to use it yourself, which I look forward to doing...

 

[riverlethe]

Quote:

Originally Posted by poo /img/forum/go_quote.gif I agree that it is probably the case from time to time, but in this particular thread, there is very little talk of acoustic impressions. Most of the information presented on these pages is fact and figures based. I don't own a DAC1 yet, but do plan to buy one based on my research - which has taken a few months. If you are serious about answering your queries, read through the 50 odd pages here as a good start to understanding the thinking and development behind the DAC1. I'm not saying it will disprove what you are questioning, but it will present you with some of the slightly different techniques used by the engineers involved in developing the product, which I believe make all the difference (such as the way audio is 'reclocked' internally). The only way to test the validity of any product is to use it yourself, which I look forward to doing...

I'm not questioning the DAC1 here. I'm questioning people who feel they need MORE than the DAC1's built-in headphone amplifier (assuming the HPA2 itself isn't overkill). I'd guess they're simply altering the FR in some way that they find enjoyable, if it isn't placebo effect. I don't think that's necessarily "wrong," but I think it could be done a lot more cheaply.
Again, I don't have much knowledge of the subject, and I'd like someone to explain if I'm wrong.

 

[poo]

I see. I'm no more qualified than you, but would tend to agree with your last comments for the most part. Again, I have not tried the DAC1 for myself so cannot provide a personal impression, but specification and information provided by Benchmark supports your point of view.

 

[Lord Chaos]

People have different perceptions, different sensitivity, different expectations. Where you stop on the path to perfection is a function of these and other factors, with finances being a big one.

I've been using DAC1s for about 9 months now, and am still delighted with them. I've heard a lot of audio equipment over the years and the DAC1--either the plain or USB subspecies--is solidly at the top of the heap... for my perceptual systems.

 

[olivier]

Hello again folks,

I am wondering what are the differences between the Benchmark DAC1 and the DAC1 USB, besides the obvious USB connection and the price tag. I read Elias mentioning several upgrades in the most recent versions of the DAC1 but I don't know if these modifications apply to both DAC1 and DAC1 or to the DAC1 USB only.

Cheers! O.

 

[tubaman]

Quote:

Originally Posted by riverlethe /img/forum/go_quote.gif I'm not questioning the DAC1 here. I'm questioning people who feel they need MORE than the DAC1's built-in headphone amplifier (assuming the HPA2 itself isn't overkill). I'd guess they're simply altering the FR in some way that they find enjoyable, if it isn't placebo effect. I don't think that's necessarily "wrong," but I think it could be done a lot more cheaply. Again, I don't have much knowledge of the subject, and I'd like someone to explain if I'm wrong.

You realize where you are? This is HEAD-FI ..the need is the the question..it's the want!.

 

[riverlethe]

Quote:

Originally Posted by tubaman /img/forum/go_quote.gif You realize where you are? This is HEAD-FI ..the need is the the question..it's the want!.

Haha, yes... I didn't mean "need" in the general sense, but "need for the purpose of accurate audio reproduction," which may or may not even be a "want."

 

[infinitesymphony]

Quote:

Originally Posted by olivier /img/forum/go_quote.gif I am wondering what are the differences between the Benchmark DAC1 and the DAC1 USB, besides the obvious USB connection and the price tag. I read Elias mentioning several upgrades in the most recent versions of the DAC1 but I don't know if these modifications apply to both DAC1 and DAC1 or to the DAC1 USB only.

Same here... I've been waiting for a comparison since little-endian's post (#964) about S/PDIF versus USB; the claim is that since the DAC1 reclocks, the type and quality of the digital input do not matter.

It's my understanding that the majority of "upgrades" took place around mid-2004, with some parts improvements here and there at later dates. But, the USB apparently has changeable gain, which allows you to tweak it for a certain pair of headphones (what euclid was talking about). If the default gain is too high, it could mean that the volume change between adjacent detents on the volume knob would be too large. With a lower gain, the knob could be turned further and with more resolution; smaller volume changes between detents.

 

[EliasGwinn]

Hey all,

Sorry I haven't been able to keep up with you...I've been pretty loaded-down with other work lately. Its good to have an escape to Head-Fi every now and then

.

There are several features specifically on the DAC1 USB which are not available on the DAC1, and they are as follows:

- Selectable gain range for headphone amp
-- Lets you select the optimal range for your specific headphones so that the volume knob can be utilized more optimally

- Main output mutes upon headphone insertion (defeatable)
-- The analog outputs on the rear of the DAC1 USB will be muted when you insert the headphone plug if this feature is enabled. This lets you switch to headphones without having to manually shut-down your loudspeaker system.

- High-Current output drivers
-- These are new OpAmps that have just come out in the last year+/-. They sound identical to the DAC1 classic output drivers, but the difference is the XLR and RCA outputs can now drive longer cables and/or low-impedance inputs and/or high-capacitance inputs without suffering loss in THD+N performance.

- Advanced USB Audio for true native, 96/24, bit-transparent playback
-- No drivers or configuration necessary...plug it in and immediately get bit-transparency at rates up to and including 96/24

- Auto-standby mode
-- When the selected digital input no longer sees digital signal (or non-compatible digital signal), the DAC1 will begin 'Standby' mode.

I hope that clears it up a bit.

Thanks,
Elias
__________