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Meridian Explorer DAC with Fedora Linux

Summary:
  •  install alsa-utils
  •  run alsamixer
  • press f6, select the Meridian DAC
  • increase the clock value to 84 
Story:
I recently became somewhat obsessive about Headphone Amplification.  I was trying to determine the value  amplification would provide.  I found that once you have nice cans, the next step should be to also invest in an upgraded DAC.  I picked up a set of Sennheiser HD380 Pro cans a while back and they made a world of difference over my other headphones.  After wearing headphones for an extended period of time at work I thought I could do better.

I stopped at JS Audio in Bethesda and the sales person was very excited to show me the USB DAC from Meridian.  The Explorer is both a DAC and an Amplifier.  Jason demo'd Beck - Lost Cause and Pink Floyd - Money.  Instantly I was convinced what I was hearing was better, but I didn't immediately know why.  (For the record - I was also listening to a pair of Fostex TH900 headphones and at one point we used the Line Out of the Explorer to run through a Fosgate Signature Headphone Amp).  The more I listened I could pick up on particular nuances that seemed to appear.  The most profound thing to recognize is any sound involving cymbals.  I don't think it is simply an influence due to the high frequency.  I believe with a better sound reproduction you can start to hear much more depth with cymbals.  It's almost as though you can hear the stick impact on the symbol (in addition to the cymbal itself) and you start to hear as though the person is hitting the cymbal in a different place.

Anyhow - I was able to demo the Meridian Explorer on a Mac Book Pro they had using FLAC.  Now - something I find interesting is the discussions (borderline arguments) regrading sample rates.  I decided to go with 192kbps a while back as I thought it would be a good trade off between quality and disk space consumption.  (this was back when I was still buying a 250GB HDD for my PC and I think the current iPod at that time was around 60GB.  I also record to mp3 which has allowed me the most flexibility between devices and operating systems (at that time I was using a Sun Sparc Workstation).  This DAC apparently will max out at 192kbps anyhow.

I got home and plugged the Explorer into my Lenovo X1 Carbon running Fedora and was anticipating bliss... well, I was sorely disappointed.  The output level was dismal.  If I simply fired up the "Sound Applet" all I was able to modify was the main output level.  I found the value at 100% and I could drive that up but as I did, the sound seemed to distort significantly.  WTF?  I plugged the Explorer into my Mac and everything worked fine.  All 3 LEDs were illuminated (indicating playback was 192kbps) and the volume control was tied directly to the standard audio controls.  :-(  Honestly I started to have thoughts of migrating use my Mac as my primary machine again.  Fortunately.. there is a happy ending.

I just happened across a doc from Meridian will searching for Linux info and they mentioned a minimum Alsa version.  Hmm... I didn't realize that alsa would play a role in the stack.
So - after a quick
# yum list | grep ^alsa | grep x86_64
I found there were a few more packages that I could install.

https://s3.amazonaws.com/hifi.nl/pdf/Explorer+FAQs+and+Tips.pdf

Now - one thing that is interesting is alsamixergui does not seem to work.  alsamixer does though.  Turn down the volume in rhythmbox (or whatever you use)
# alsamixer
-- hit f6 to select another sound device
-- configure both Meridian Clock Selectors to around 84 (any higher and the bar turns red - I assume that is not as desirable)
you can now modify the volume from rhythmbox

[root@cyper ~]# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC269VB Analog [ALC269VB Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: DAC [Meridian Explorer USB DAC], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
[root@cyper ~]# alsamixer -c=1


Comments

  1. Thanks for the write-up. Seeing that the Meridian Explorer won the EISA award for being the best USB-DAC it's very nice to read that it also works on Linux! Will buy it for my Thinkpad too!

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