Benchmark DAC1 now available with USB

[music_man]

i know this probably does not matter with the dac1. in general is it true that the best coaxial cable length for avoiding jitter is 3 meters?

thanks,
music_man

 

[Prog Rock Man]

Much obliged for the reply Elias. Thanks.

 

[Bmac]

Well, I've had my DAC-1 PRE for a few months now and have slowly been wading through this thread. I'm finally finished. I feel like I've just earned my undergrad in DAC-1.

I bought it before I found this thread, and once I saw this I thought it would be worthwhile to read through. Little did I know at the time that I had stumbled upon one of the most informative and interesting threads in all of the internets. What Elias has done here is real testament to the customer service of Banchmark and his presence and dedication has really served to reinforce my satisfaction with the DAC-1 purchase.

I'm using it with some Dynaudio BM5A's, an HSU sub and headphones (AKG K701, K270 Playback, Grado SR60, Shure E4G). The transparency of the DAC-1 is awesome. I've had some other decent quality DAC's in this system, the Neko D100, the Music Hall 25.2 and an Essence STX. There were things I liked about all of them, but prefer the DAC-1 PRE to the others by a good margin. It's really an awesome piece of equipment.

After having gone through here, I do have a few questions I was hoping Elias could address.

The first is in regards to J. River Media Centre. Fairly early on in this thread some people had asked if you had ever done any testing with it, and you hadn't at the time, and there is still nothing in the Benchmark Wiki with regard to it. I was just wondering if you ever had a chance to play with it and if there were any settings that you could recommend for bit-perfect playback. I only use J. River with FLAC files and just want to make sure that I am getting the best possible quality from the pc side.

I know for other programs that you've recommended using a 24-bit word length so that if digital volume control is used or the bits are otherwise somehow altered that the 24-bit word won't be truncated to 16-bits. In J. River, you can choose 16-bit, 24-bit, or use the native word length of the file. I have all volume controls set to 100%, so I have been using the native word length. J. River seems to recommend setting it to 16-bit, which doesn't seem like a great idea to me, so this is why I'm wondering if you have tested it, to see if there is a preferred setting.

The second is just a general question with regard to Windows 7 audio. I know you did testing with XP, but didn't see much information with regards to Vista and Windows 7 audio. Have you done much testing with these OS's? I believe I read somewhere in the thread that there was no way to bypass SRC in Vista/7 unless using asio/kernel streaming, so even if playing a 16/44.1 file and having the sounds in the control panel set to 24/44.1, Windows will still resample, but the sample rate conversion is of such high quality that it won't degrade the audio. Is this correct? Or is there a way to bypass the Windows SRC with the proper settings?

I've tried WASAPI, but occasionally when I do other things while listening the audio will get buggy, skip and not sound right. I can't say I noticed a difference in sound quality whether using kernel streaming or not, so my settings right now in J. River are to playback at the source sample rate and bit-depth, all volume set to 100%, with sounds in the OS set to 24/44.1. I'm extremely happy with the sound from the Benchmark DAC-1 PRE as it stands, but would really appreciate knowing if you think there is anything I could do to improve these settings.

Thanks.

 

[Roseval]

It is very easy to bypass the mixer in Vista/Win7
This is called WASAPI (MS own ASIO) and J River has an interface for it
As WASAPI does ‘nothing’, it talks straight to the sound card, what the player send to WASAPI must match the capabilities of the audio device.
I got the DAC 1 to work both over SPDIF and USB
The screenshots with the J River settings can be found here: The Well Tempered Computer

 

[Bmac]

I've used WASAPI with J. River with the exact settings that were in the link. My previous post where I said kernel streaming was a typo and I've edited it. My problem with WASAPI is that if I do other things besides just music it can cause problems with the audio; it starts getting really choppy and just sounds weird, so for the time being I am just using DirectSound.

 

[music_man]

i have a cd that has some very minor "skipping". the cd looks fine. obviously it is a laser tracking error for some reason. isn't the dac1 supposed to "fix" an issue like this so the disc plays properly? or can nothing fix a read error? i thought that is what "error correction" or oversampling is for?

thanks,
music_man

 

[EliasGwinn]

Quote:

Originally Posted by music_man /img/forum/go_quote.gif i have a cd that has some very minor "skipping". the cd looks fine. obviously it is a laser tracking error for some reason. isn't the dac1 supposed to "fix" an issue like this so the disc plays properly? or can nothing fix a read error? i thought that is what "error correction" or oversampling is for? thanks, music_man

The DAC1 can't fix data errors, only clock errors. If the data is not received at the DAC1, it cannot 'generate' that data. It can only alleviate deviations from ideal clock cycles.

All the best,
Elias

 

[wgb113]

I read about 12% into the thread before my head started spinning and I'll continue to read but I need the help of Elias and all of you DAC1 users because I've got my finger on the trigger:

1) How have the DAC1 and DAC1 USB changed over the years in terms of hardware and performance? I am looking for a pre-owned unit but will go new if any changes are significant.

2) My plan is to connect my iMac to the DAC1 and use it with a pair of AKG K701 and Dynaudio BM5A or BM6AmkII. Any experience you all might have as to how they match up with the DAC1 is appreciated.

A used DAC1 USB for the price of a new DAC1 seems to be my sweet spot at the moment.

Bill

 

[wgb113]

Alright, in fear of flames I searched the thread for Dynaudio and AKG and read the correspondence...Bmac has a nearly identical system as what I'm after.

Still looking for answers to the first question.

Will the DAC1 USB's high current output op-amps on the output stage only be noticeable with my proposed setup?

Will only 2 selectable gain ranges on the headphone amp suffice?

The auto mute and standby functions are nice-to-haves but not deal breakers for me.

Bill

 

[music_man]

thank you once again mr. gwinn.

i understand that no device can "create" missing data. i do not know what made me think that last night. i do not know why this disc skips twice always in the same exact place. there are no visable scratches. it must be a bad recording. pretty minor issue though.

music_man

 

[wgb113]

So from reading the owner's manual for the DAC1 USB it appears that the ability to adjust the gain on the headphone outputs would benefit someone with a set of 62 ohm AKG 701s as well as a pair of 300 ohm Sennheiser 580s. Where would you place the jumper for each and would it constantly have to be changed???

Bill

 

[revenge]

Although a low impedance headphone, K701 is quite inefficient so it takes a lot of power to make it sing. I'm pretty sure that whatever setting works for HD580, will work for K701 as well (I used to set the gain on my Prehead to high for both). Ideally you should use the headphone amp with the volume knob around 12. Unfortunately for my Ultrasone Edition 8, even the lowest gain on my DAC1 HDR is still way too lound for anything above 10 but for your headphones the high gain should be perfect. Mind you, I doubt K701 will be a great performer with DAC1.

 

[wgb113]

Thanks for the input.

Why do you feel the AKG 701 and DAC1 won't perform well together? I am looking for a highly analytical sound.

Bill

 

[revenge]

Well, you know it's not all about power and resolution. Sinergy is also a very important factor and generally K701 is better matched with tubes or a warmer SS with enough power and plenty of bass.
I haven't tested my K701 straight out of the Benchmark yet, but I have tried it with my Lavry DA10 and I haven't been impressed at all. Considering the Lavry is a bit more musical (or let's say warmer) than the Benchmark, I think it's fair to expect a highly analytical sound indeed, but leaning toward the bright side of things, with a lean bass and mediocre soundstage.

 

[wgb113]

Quote:

Originally Posted by revenge /img/forum/go_quote.gif Well, you know it's not all about power and resolution. Sinergy is also a very important factor and generally K701 is better matched with tubes or a warmer SS with enough power and plenty of bass. I haven't tested my K701 straight out of the Benchmark yet, but I have tried it with my Lavry DA10 and I haven't been impressed at all. Considering the Lavry is a bit more musical (or let's say warmer) than the Benchmark, I think it's fair to expect a highly analytical sound indeed, but leaning toward the bright side of things, with a lean bass and mediocre soundstage.

I can appreciate that viewpoint but those "nasty" descriptives of clinical/analytical are exactly what I'm after with this system. If I want warm distortion that I also find appealing for a change I'll just listen on my other system. Neither is right or wrong, but what YOU want. Anyhow, that's another thread.

So back to Benchmark, I think I'm going to focus my search on a DAC1 USB.

Bill