Benchmark DAC1 now available with USB

[little-endian]

Hi Elias,

yesterday, I've just recognized that the DAC1 responds to the 217 Hz burst used by GSM-compatible mobile phones as well and wondered why.

Is it so difficult to shield this and prevent interspersing the audibly buzzing? And how about the ADC1 - would an audio engineer have this sound in his recording when he forgets his mobile in the near which might acknowledge a short message arriving by chance?

For your information: currently I'm using the DAC1 in conjunction with the HD-650 only.

[infinitesymphony]

Motorola have some sort of solution for the GSM buzz, but it doesn't sound like anything desirable for the audio chain.

[riverlethe]

Even if they shielded the DAC1, you would still get noise in any other cable or audio device in proximity. The signal is strong enough to turn my monitors on from standby.

[little-endian]

Well, actually it's not a big problem at all (at least I presume that no harm to the hardware is done by this interference). I was just interested if the DAC1 would "react" to this. I always thought that just radio receivers were especially prone to this by nature.

[G-U-E-S-T]

Hi Elias,
I am interested in trying the new DAC1 Pre with some active Quad 12L speakers. I would also like to use my subwoofer. Is there any problem using both the XLR outs and the RCA outs simultaneously on the DAC1 Pre? I've been told that the DAC1 Pre's output impedance, and the driving current, would suffer (due to the power supply stress of all outputs simultaneously being used) - and also that the balanced operation of the DAC1 Pre's XLR outs would also be compromised when driving both balanced and unbalanced outputs simultaneously. But I would like to confirm all this with you. Could you please comment on these concerns, and also give any other advice you may have for my application? Thanks!

[Covenant]

I'm sorry if this question has been asked already, i read through the first 25pgs before i couldnt absorb information any longer

I am considering purchasing a DAC1 for use in a balanced system, running the XLR outputs to a balanced B22 amplifier. One thing that AMB specifically cautions against with the B22 is to ensure that there is no DC offset at the source, as the amp design does not handle this well.

Mr Elias, does the DAC1 (USB or non-USB) measure any DC offset at its outputs, either unbalanced or balanced?

Thank you again for your time and patience. Its awesome to see a product in the (often snake-oil laden) audiophile industry so well backed up by the engineers who designed it, kudos to you

[riverlethe]

Originally Posted by little-endian

Well, actually it's not a big problem at all (at least I presume that no harm to the hardware is done by this interference). I was just interested if the DAC1 would "react" to this. I always thought that just radio receivers were especially prone to this by nature.

I've heard cell phone noises if I had it near my headphone cable. There was even a study recently saying that sleeping too close to your cell phone can disrupt your sleep cycle...

[Covenant]

Or if Elias isnt available to post, have any of the DIYers checked the DAC1's outputs for DC offset?

[little-endian]

Originally Posted by riverlethe

I've heard cell phone noises if I had it near my headphone cable.

Hmm, maybe it has even nothing to do with the DAC1 in this case but the noise is inducted directly into the cable.

Originally Posted by riverlethe

There was even a study recently saying that sleeping too close to your cell phone can disrupt your sleep cycle...

I've heard that, too. However depending on the network's "Periodical Location Update (PLU)", I wouldn't give too much about this. In the case of the German provider T-Mobile for instance, the mobile will send an update every 6 hours while just listening the other period. Hence the exposure should be almost zero when in standby.

[Terje]

A DAC1 computer audio tweak
Odyssey Audio HK Forum - eeepc + Benchmark DAC1 Pre = great sound!