[EliasGwinn]

Quote:

Originally Posted by Kiep /img/forum/go_quote.gif I can create suitable waveforms for the input and I can use Behringer DEQ2496 to measure the output signal. What frequency/level would you recommend? I will measure the current output as reference before I change anything. Thank you in advance.

1kHz sine wave @ -1 dBFS would be a suitable test signal.

Thanks,
Elias

 

[cansman]

Hi Elias,

I read John's response in Stereophile that iTunes 7.5 is a lemon!

iTunes 7.6 has just been released - it is also included in the 10.5.2 massive upgrade. Would you know whether the bug has been fixed?

Bit accuracy...sigh!

Thanks and regards,
cansman

 

[EliasGwinn]

Quote:

Originally Posted by cansman /img/forum/go_quote.gif Hi Elias, I read John's response in Stereophile that iTunes 7.5 is a lemon! iTunes 7.6 has just been released - it is also included in the 10.5.2 massive upgrade. Would you know whether the bug has been fixed? Bit accuracy...sigh! Thanks and regards, cansman

Cansman,

Actually, since that response was published, we had some extended correspondence with the engineers at Apple, and we also conducted further testing on iTunes 7.5. It turns out that CoreAudio, NOT iTunes, was causing the problems.

Here is a follow-up response that I wrote for Stereophile (its also published in the "Manufacturer's Comments" section of the March '08 magazine):

Stereophile: Third Time Lucky?

As noted in this response, iTunes 7.5 actually is capable of high-quality playback (even bit-transparency), but it requires a thorough understanding of how iTunes and CoreAudio work together.

Let me know if anything is unclear in that article...

Thanks,
Elias

 

[riverlethe]

How should software EQ be used with digital output? Should bands only be reduced rather than increased, or doesn't it matter? Do you know if the graphical equalizer in Windows Media Player 11 causes distortion?

 

[EliasGwinn]

Quote:

Originally Posted by riverlethe /img/forum/go_quote.gif How should software EQ be used with digital output? Should bands only be reduced rather than increased, or doesn't it matter? Do you know if the graphical equalizer in Windows Media Player 11 causes distortion?

Riverlethe,

All EQ's cause distortion - intentional distortion. In other words, they distort the frequency response.

Since our company's philosophy is to establish the most transparent playback system, we do not recommend using EQ on playback.

However, if you decide you want to use EQ, I would recommend using subtractive EQ'ing (that is, reducing frequencies) as much as possible, and always more then additive EQ'ing. The reason for this is because additive EQ'ing may increase the overall level of the signal to a degree which causes clipping ('digital overs'). Digital-overs are never pretty, so you'd be wise to cut at least as much as you boost.

Thanks,
Elias

 

[cansman]

Quote:

Originally Posted by EliasGwinn /img/forum/go_quote.gif Cansman, Actually, since that response was published, we had some extended correspondence with the engineers at Apple, and we also conducted further testing on iTunes 7.5. It turns out that CoreAudio, NOT iTunes, was causing the problems. Here is a follow-up response that I wrote for Stereophile (its also published in the "Manufacturer's Comments" section of the March '08 magazine): Stereophile: Third Time Lucky? As noted in this response, iTunes 7.5 actually is capable of high-quality playback (even bit-transparency), but it requires a thorough understanding of how iTunes and CoreAudio work together. Let me know if anything is unclear in that article... Thanks, Elias

Thanks Elias for clarifying. I believe everything you said in the article is the same as previous advice for achieving bit-transparent playback with OSX and iTunes. Thanks. That's good to know!

Kind regards,
cansman

 

[dspargo]

Hello Elias,

How do I connect my Benchmark DAC1 USB to my Wooaudio 6 which has RCA inputs. I want to use the balanced outputs on the Benchmark. I am already using the RCA outputs from the Benchmark and they go to the RCA inputs on my Meier Opera.

Thanks,
Don

 

[poo]

Quote:

Originally Posted by dspargo /img/forum/go_quote.gif Hello Elias, How do I connect my Benchmark DAC1 USB to my Wooaudio 6 which has RCA inputs. I want to use the balanced outputs on the Benchmark. I am already using the RCA outputs from the Benchmark and they go to the RCA inputs on my Meier Opera. Thanks, Don

You need a cable with XLR connections on one end for the DAC1, and rca on the other. Remember to ensure that the XLR end is connected properly as per instructions in the manual - which explains that you must leave pin 3 floating.

I am using my DAC1 USB in the same way - sounds great!

 

[joijwall]

Elias,
First of all congratulations to the DAC1 Pre, I hope it will be a great success!

I'm still a bit shaky about the correct use of my DAC1 USB and I would appreciate your advice. I'm on a MacBook with the recent 10.5.2 and iTunes 7.6/QuickTime 7.4.1. As backup player I use VLC 0.86d, since you pointed out VLC earlier as very good.

1) Is there any difference for DAC1 if use the USB or the optical output from my MacBook? In the shop where I bought DAC1 they said USB is far better.

2) Will the sound from DAC1 change after some playing? I have the feeling that playback has become a bit "softer" compared to the beginning?

3) iTunes is my main player. But my impression is that VLC sounds "better". That is clearer, airer, more at ease. Is there perhaps some settings I missed in iTunes?
a) I use 24 bit and 44100 in CoreAudio, which I understand is the best setting for AppleLossless for both VLC and iTunes. I haven't seen in the wiki how VLC performs if I set it CoreAudio to 96000. Volume settings is disabled in my CoreAudio.
b) I've found the Equalizer Window in iTunes and turned it off (preset set to "Flat" just in case)
c) In iTunes settings for Playback I've unchecked Sound Enhancer and Sound Control.
d) iTunes volume is set to max
e) I've also found the picture/sound setting window in QuickTime, which has full volume, and balance, treble and bass in the middle. I can't find a way to turn it off, and I can't find the Equalizer although a setting is called "Show Equalizer".
f) VLC has volume set to 100% (256), equalizer and others off.

4) I've read in the wiki that iTunes uses QuickTime. Will QuickTime Player give the same bits to DAC1 as iTunes?

5) Are Apple interested in bit transparancy, or is that of minor interest for them?

6) When do you think your Leopard testing is ready for the wiki?

By the way, many of my hifi friends has suddenly become interested in a different approach back home after visiting me.

Joachim

 

[Terje]

Quote:

Originally Posted by poo /img/forum/go_quote.gif You need a cable with XLR connections on one end for the DAC1, and rca on the other. Remember to ensure that the XLR end is connected properly as per instructions in the manual - which explains that you must leave pin 3 floating. I am using my DAC1 USB in the same way - sounds great!

I assume you have done a comparision between rca-rca and xlr-rca?
My thougts is that it is best to use xlr-xlr. If not possible, rca-rca is better. The same connection in both ends.

 

[roadtonowhere08]

Hi all,

I just got a DAC1 (non-USB), and so far I love it. I have a question though. I am used to an E-MU 1212M and an ESI Juli@ driving my Face Audio F500TS balanced. I have noticed that at stock and with the volume set to calibrated, the signal is much lower than the two aforementioned sound cards, and I have to turn up the volume on foobar higher. Before I could get a good level at around -40dB on foobar, and now I have to go to around -25dB to get about the same sound level. In addition, this makes my sub much louder than the mains due to their (I believe) lowered input level into the amp. I am pretty sure that this is due to the XLR jumpers, so I am wondering if I can set them to -10 or even 0. Am I correct in thinking that setting them to 0 would be the same as passing an unaltered balanced signal to my amp with identical gain as the sound cards?

Just in case I am wrong, the input sensitivity of my amp is .775V if that helps at all. Thanks in advance for any help

 

[sejarzo]

Quote:

Originally Posted by roadtonowhere08 /img/forum/go_quote.gif I just got a DAC1 (non-USB), and so far I love it. I have a question though. I am used to an E-MU 1212M and an ESI Juli@ driving my Face Audio F500TS balanced. I have noticed that at stock and with the volume set to calibrated, the signal is much lower than the two aforementioned sound cards, and I have to turn up the volume on foobar higher. Before I could get a good level at around -40dB on foobar, and now I have to go to around -25dB to get about the same sound level.

You shouldn't be using any digital attenuation in Foobar if you want the best quality......it reduces volume by reducing resolution (hacking off bits to reduced the digital signal level.)

Run all volume controls in any software at 100%, control volume via the pot on your DAC-1, and rebalance your sub.

 

[roadtonowhere08]

Quote:

Originally Posted by sejarzo /img/forum/go_quote.gif You shouldn't be using any digital attenuation in Foobar if you want the best quality......it reduces volume by reducing resolution (hacking off bits to reduced the digital signal level.) Run all volume controls in any software at 100%, control volume via the pot on your DAC-1, and rebalance your sub.

I read that foobar uses 64 bit volume attenuation, but I could be wrong. Honestly, I cannot hear any difference when I use foobar's volume control, so I want to keep using that.

I am just wondering if I move the jumper to 0 instead of -20dB, will I be getting a regular +4dB balanced signal, or is it a higher rated signal? If it is a regular balanced signal, I read that a higher signal running from the DAC to the amp will increase SNR. However, if someone is sure that running a jumper at 0 will clip my amp, I will not even bother opening it up.

It is odd though that my amp's pots are at the 11 position in a 7 to 5 range, and it is a rather beefy power amp. The pots used to be at the 9 position when using both of my balanced sound cards. I just want a confirmation that changing the jumpers will not clip the amp's inputs.

 

[poo]

Quote:

Originally Posted by Terje /img/forum/go_quote.gif I assume you have done a comparision between rca-rca and xlr-rca? My thougts is that it is best to use xlr-xlr. If not possible, rca-rca is better. The same connection in both ends.

Using both RCA-RCA and XLR-RCA. I don't hear any difference, nor should I - both are terminated the same way for the DAC1 - you leave pin 3 floating for the XLR-RCA cable.

 

[sejarzo]

Quote:

Originally Posted by roadtonowhere08 /img/forum/go_quote.gif I read that foobar uses 64 bit volume attenuation, but I could be wrong. Honestly, I cannot hear any difference when I use foobar's volume control, so I want to keep using that.

As far as I know, regardless of how accurately Foobar calculates the attenuated output by increasing bit depth in the calculation, the reality is that it ends up sending a lower resolution/manipulated signal to the DAC1.

Someone correct me if I'm wrong, but if you require 25 dB of attenutation, I'm fairly certain that's virtually reducing 16-bit recordings to 12-bit.