Benchmark DAC1 now available with USB

[G-U-E-S-T]

Hi Elias,

I read your online post regarding the use of the DAC1 directly connected to the amp, where you advise the following:

Quote from Elias Gwinn: "Avoid using amplifiers that are too powerful for your system! You'll get best results when using 75-95% of the amps total power."

I always thought it was better to have more clean amp power on tap to properly handle musical transient peaks, similar to what Musical Fidelity advises at this link (also note their interesting "System Diagnostic" link on that page). I have been using a powerful (255W @ 8-ohm) Musical Fidelity stereo amplifier with some very nice 7-ohm minimum bookshelf speakers. After reading your quote above, I'm now wondering if my amp is "too powerful" and whether optimally I should change this.

Please advise? Thanks again, in advance.

 

[roadtonowhere08]

Quote:

Originally Posted by G-U-E-S-T /img/forum/go_quote.gif Hi Elias, I read your online post regarding the use of the DAC1 directly connected to the amp, where you advise the following: Quote from Elias Gwinn: "Avoid using amplifiers that are too powerful for your system! You'll get best results when using 75-95% of the amps total power." I always thought it was better to have more clean amp power on tap to properly handle musical transient peaks, similar to what Musical Fidelity advises at this link (also note their interesting "System Diagnostic" link on that page). I have been using a powerful (255W @ 8-ohm) Musical Fidelity stereo amplifier with some very nice 7-ohm minimum bookshelf speakers. After reading your quote above, I'm now wondering if my amp is "too powerful" and whether optimally I should change this. Please advise? Thanks again, in advance.

It is better to have too much beef than to run of of it and damage you speakers with clipped beef. That is what the volume knob is for. Never go over a certain point, and you will be fine.

All speakers have a dynamic wattage rating that is higher than the continuous rating. This is for large transients. The beefier amps are good for dynamics.

 

[mrarroyo]

roadtonowhere08 you are correct, at one time power amps and the better receivers had a "headroom" of 3 dB over the continuous output. This meant that a 200 wpc amp that had a 3 dB headroom could have peaks at 400 wpc.

I also believe that more speakers are damaged by clipping caused by an anemic amp for the application than too much power.

 

[Bach-Fan]

Elias, if I buy a DAC1 HDR today, will it work seamlessly with a computer running the 64-bit version of Windows 7 - due out in 3 months?

 

[HeadLover]

I have mine working with win 7 RTM 64 bit

Working just great!!!

 

[EliasGwinn]

Quote:

Originally Posted by Xxtest83 /img/forum/go_quote.gif Hello, is it possible to set either RCA or XLR out to "calibrated" and the other one to "variable" ?

No, the output mode applies to both the RCA and XLR.

All the best,
Elias

 

[pcf]

Quote:

Originally Posted by EliasGwinn /img/forum/go_quote.gif No, the output mode applies to both the RCA and XLR. All the best, Elias

Hi Elias,

Can you advice on how to use an XLR-RCA cable to gain an extra output on The Benchmark? I seem to remember it was mentioned before but couldn't find it through all these pages.

Thanks!

Paul

 

[EliasGwinn]

Quote:

Originally Posted by G-U-E-S-T /img/forum/go_quote.gif Hi Elias, I read your online post regarding the use of the DAC1 directly connected to the amp, where you advise the following: Quote from Elias Gwinn: "Avoid using amplifiers that are too powerful for your system! You'll get best results when using 75-95% of the amps total power." I always thought it was better to have more clean amp power on tap to properly handle musical transient peaks, similar to what Musical Fidelity advises at this link (also note their interesting "System Diagnostic" link on that page). I have been using a powerful (255W @ 8-ohm) Musical Fidelity stereo amplifier with some very nice 7-ohm minimum bookshelf speakers. After reading your quote above, I'm now wondering if my amp is "too powerful" and whether optimally I should change this. Please advise? Thanks again, in advance.

I agree with them, for the most part. I'll clarify my statement:

It is best to have an amplifier whose input peaks at the same level as the maximum output level of the source (e.g., DAC, PRE), and this amplifier/speaker combination should only be "loud" enough so that maximum comfortable listening levels are acheived near peak input (transient peaks reach full-scale). In other words, it is ideal to use ALL of your headroom without going over.

The reason for this is to acheive the best possible dynamic range. If you must attenuate the source to prevent the amplifier/speakers from becoming too loud for comfort, then you are losing dynamic range. The amount of dynamic range you are losing is equivelant to the amount of attenuation you are employing.

The reason is that the amplifier has a specified noise floor. This noise doesn't attenuate when the source is attenuated. So, when the source is attenuated, the result is lower signal-to-noise ratio.

In a high-precision playback system, amplifiers are typically the limiting factor in dynamic range. If your amp is too powerful for your typical listening levels, you will attenuate your source and decrease your dynamic range even further.

Does this make sense to you?

All the best,
Elias

 

[EliasGwinn]

Quote:

Originally Posted by roadtonowhere08 /img/forum/go_quote.gif It is better to have too much beef than to run of of it and damage you speakers with clipped beef.

It is true that clipping your amp can damage your tweeters because of the increase in high-frequency content. You certainly don't want to operate a power amp into clipping.

I would also agree that it is better to error on the side of too much headroom rather then not enough.

However, the idea of "the more headroom the better" is not true.

All the best,
Elias

 

[EliasGwinn]

Quote:

Originally Posted by Bach-Fan /img/forum/go_quote.gif Elias, if I buy a DAC1 HDR today, will it work seamlessly with a computer running the 64-bit version of Windows 7 - due out in 3 months?

We don't have Windows 7 yet, so I haven't tested it yet. But several customers have done it successfully (including one responding to your post).

All the best,
Elias

 

[EliasGwinn]

Quote:

Originally Posted by pcf /img/forum/go_quote.gif Hi Elias, Can you advice on how to use an XLR-RCA cable to gain an extra output on The Benchmark? I seem to remember it was mentioned before but couldn't find it through all these pages. Thanks! Paul

The XLR connector must have a floating pin-3 (nothing connected to it). Pin 2 is connected the center pin of the RCA, and Pin 1 is connected to the outer-casing of the RCA. Again, pin-3 is not connected to anything.

Here is the cable:

Benchmark Media

All the best,
Elias

 

[denp]

Quote:

Originally Posted by bralk /img/forum/go_quote.gif For large scale reproduction you need large speakers. I can recommend ATC SCM 100 ASL or perhaps the SCM 50 ASL depending on your listening environment. cheers Tom

I also happen to use SCM100A connected directly to HDR DAC1 / PRE - I can testify it's an incredible match!

What's also recommended is to shift the attenuation to -30dB; First this improves the usable Volume range (in my case), second it lowers the Output impedance of the DAC1/PRE to 43 Ohms, which is greatly desired by the ATCs!

Having used the ATC with a bunch of other DAC & PRE combos, I can say DAC1/PRE fits the bill very well. Overall creates a more insightful (musically) combo than any other one I tried with the ATCs..

 

[pcf]

Quote:

Originally Posted by EliasGwinn /img/forum/go_quote.gif The XLR connector must have a floating pin-3 (nothing connected to it). Pin 2 is connected the center pin of the RCA, and Pin 1 is connected to the outer-casing of the RCA. Again, pin-3 is not connected to anything. Here is the cable: Benchmark Media All the best, Elias

Thanks Elias!

Paul

 

[gevorg]

Quote:

Originally Posted by EliasGwinn /img/forum/go_quote.gif I agree with them, for the most part. I'll clarify my statement: It is best to have an amplifier whose input peaks at the same level as the maximum output level of the source (e.g., DAC, PRE), and this amplifier/speaker combination should only be "loud" enough so that maximum comfortable listening levels are acheived near peak input (transient peaks reach full-scale). In other words, it is ideal to use ALL of your headroom without going over. The reason for this is to acheive the best possible dynamic range. If you must attenuate the source to prevent the amplifier/speakers from becoming too loud for comfort, then you are losing dynamic range. The amount of dynamic range you are losing is equivelant to the amount of attenuation you are employing. The reason is that the amplifier has a specified noise floor. This noise doesn't attenuate when the source is attenuated. So, when the source is attenuated, the result is lower signal-to-noise ratio. In a high-precision playback system, amplifiers are typically the limiting factor in dynamic range. If your amp is too powerful for your typical listening levels, you will attenuate your source and decrease your dynamic range even further. Does this make sense to you? All the best, Elias

What if your amplifier has gain controls, will that help to improve dynamic range? Or its the same as attenuating at the source? For example, say a low-impedance and high sensitivity headphones are too loud at 20% of maximum volume of a given powerful amplifier. Then you reduce the gain inside amplifier so that the maximum listenable volume increases to around 50% of maximum volume. At the same volume level, will the dynamic range improve?

 

[Shadorne]

Quote:

Originally Posted by denp /img/forum/go_quote.gif I also happen to use SCM100A connected directly to HDR DAC1 / PRE - I can testify it's an incredible match! What's also recommended is to shift the attenuation to -30dB; First this improves the usable Volume range (in my case), second it lowers the Output impedance of the DAC1/PRE to 43 Ohms, which is greatly desired by the ATCs! Having used the ATC with a bunch of other DAC & PRE combos, I can say DAC1/PRE fits the bill very well. Overall creates a more insightful (musically) combo than any other one I tried with the ATCs..

DITTO Here. We must start a "club"

I also use the DAC1 with Active ATC 100's. I read somewhere that Doug Sax installed DAC1 with ATC's in his new Mastering Lab in Ojai, Califoria. So it sure seems like a great combo to a few folks. I did some tests myself and the improvement with the DAC1 versus other sources was substantial. I suspect you really hear the phase accuracy of this DAC when using phase compensated Active speakers (speakers which are about as good as it gets in transient response).