Need Help!

I'm on a Macbook Pro with my Bose QuietComfort (??) headphones on. No DAC, headphone amp, etc.

I'm on the HDTracks site listening to "Northern Timbre" by Ragnhild Hemsing. I select between the 2 sample rates in the Subject and listen. But I can't tell a difference. With my minimal setup, should I be able to tell a difference?

I don't want to pay $35 for a hi-res download and then not being able to hear a difference on my home system. (Emotiva amp & pre-amp connected to my PC via an HDMI cable. No exterior DACs, line conditioners, etc.)

Thoughts?

Hi Michael,

It looks like there are several models of Bose QuietComfort headphones. Which model are you using? How are the headphones connected to your Macbook Pro (1/8" jack, Bluetooth)? I don't believe that the DAC that's internal to the Macbook Pro supports sampling rates higher than 96kHz.

The DAC and headphone amplifier that are internal to the Mac are adequate for background music but definitely not sufficiently resolving to hear differences among CD and higher resolution source files (assuming that they are made from the identical master). They may not even be sufficiently resolving to hear the difference between 256kbps MP3 and 24-bit, 96kHz AIFF files.

The second problem is the music samples on the HDtracks website. These are encoded as Adobe Flash files, almost certainly with lossy encoding. So, even if you have selected a the high resolution version of an album, you are only getting 44.1kHz audio...probably with a rather high lossy compression setting. I believe the purpose here is more for you to see if you like the music on the particular album than to assess the quality of the delivery format. The sound you are hearing in these samples is not representative of the tracks you will purchase.

Hi David,
Thank you for your reply. I wasn't feeling well last night, which is why I didn't reply then.

I just checked; I'm using the QC 15 model which is connected via the 3.5mm jack.

Wow, I've definitely got some drawbacks while on my Mac laptop.   I see I'll need to get a portable DAC so I'll be able to listen to higher res music.

I definitely didn't know that all of the samples would be the same rate. I was thinking that my ears were really failing me.

Michael

Oh...it sounds like you may have the Emotiva XMC-1 pre/pro (or similar). I have one also. It has a decent internal DAC; however, HDMI is not the highest quality interface on the XMC-1 for listening to digital music. This forum post explains some of the inherent problems with HDMI audio: http://www.avsforum.com/forum/86-ultra-hi-end-ht-gear-20-000/1296730-hdmi-asynchronous-does-clock-j

For critical listening, I highly recommend that you use either the USB audio or one of the COAX S/PDIF inputs instead. Also, instead of directly connecting your PC to your pre/pro, buy a network audio adapter like the SOtM sMS-200, Sonore Sonicorbiter SE or microRendu, or a Raspberry Pi running Roon Bridge. These devices are small, lower power, fanless, completely silent, and produce no vibrations. Using one of these devices enables you to remove the PC from listening room. This will lower the noise floor and allow you to hear more deeply into your music, potentially revealing the subtle differences between CD and higher resolution formats, etc.

Until you are able to use a connection that's better than HDMI from a directly attached PC, I recommend against investing in high resolution content. Even then, the DAC in the Emotiva is limited to 192kHz, so that content will have to be sample rate converted to 176.4kHz. If you truly want to experience sampling rates above 192kHz, you will also need to invest in an external DAC.

I don't mean to sound critical if your current setup. I just want you to know what changes are required in order to hear what you are hoping to hear so that you can decide for yourself if this is something worth exploring. I know there are several members of the A-VCOA who would be happy to have you come over to hear the differences in these formats on a more resolving system. I encourage you to leverage that resource. You're welcome to come by my place as well...but I live in San Jose, CA, so it's almost certainly more convenient for you to sync up with Lee or someone who's local to the Atlanta area. :)

I hope this helps...

David,
Wow!!! That was extremely nice and helpful! Thank you VERY much for providing all of this information. Most of products I have not heard of before. 

I will definitely look into getting an external DAC. I have the XMC-1 pre-amp and the 7-ch XPA Gen 3 amp. I actually emailed their tech support asking if it would help to buy an external DAC but they told me the following. So I thought I was good.


I need to do some homework so I get the correct setup - in terms of ability and good sound. I will look into all of those products as well as review the article about HDMI connections. I had used HDMI so I could have the music as well as be able to select playlists from Tidal or stations from Pandora.

I don't think you're being critical of my system at all. You're just helping me to be informed based on what I have. (I didn't know the hi res limit of the XMC-1.)

Although San Jose is probably a great place I think it might be a "tad" easier to find someone local.

Thanks again for a very thoughtful and helpful response!!

Michael