T8S Analog vs Digital Connection to L1® Model II or L1® Model 1S

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T8S This information is applicable to the T8S ToneMatch® mixer
L1 Model II This information is applicable to the L1®  Model II
L1 Model 1S This information is applicable to the L1®  Model 1S

Fountain Pen

This article is an editorial and expresses the opinion and experience of ST the author. Please post comments in the T8S Analog vs Digital Connection to L1® Model 1S and L1® Model II discussion.
Thank you.


Some people have expressed concern because the T8S ToneMatch mixer does not have ToneMatch (digital) connections to L1 Model 1S and L1 Model II.

To my ears, there is no audible difference between the digital and the analog connections. This brief article explains how I tested.

Background

Bose has told us

We tried to make it (full ToneMatch port for digital output) happen for the T8S but powering the T8S from an L1 was not meeting our requirements so we opted for an external power supply which ships with the T8S. While the digital connection is nice, your experience will be fine with a balanced TRS connection between the T8S and L1 Model II.

Testing

The best way I know to detect differences in sound is to do an A/B switch back and forth instantly. Even a few seconds between listening events can lead to misconceptions.

There's no way to make a direct comparison of digital and analog on the T8S because there is no digital output. But on the T4S, you can switch instantly between digital and analog. So I started my A/B listening tests with the T4s.

Connections

Connections from the T4S to the L1 Model II (and later L1 Model 1S)

  • T4S Ethercon cable from T4S Right Channel to L1® Model II power stand ToneMatch (digital) input
  • Balanced 25-foot cable from the T4S Left Channel analog output to the  L1® Model II power stand analog input
  • USB B from PC directed Left to Channel 3
  • USB B from PC directed Right to Channel 4
  • Channel 3 panned hard Left
  • Channel 4 panned hard Right
  • Levels so the volume was the same whether I was running analog or digital
  • Tested by alternating Channel 3 and Channel 4 MUTE buttons so I could switch back and forth instantly
  • Swapped source Left and Right (USB B from PC)
  • Tested with L1 Model 1S
  • Listened at moderate and loud volume

I tried several high-res and lossless audio files on the computer and switched back and forth from analog to digital and back. I made sure I could not see the buttons as I swapped A/B, so I had no visual cue to tell me whether I was listening to analog or digital. I could not hear a difference.

Then I tried comparing the T4S and the T8S. This was harder to do because I couldn't swap back and forth instantaneously without adding a switching device into the signal chain.

Conclusions

I could not hear a difference between the T4S digital and the T8S analog outputs on the L1 Model 1S or Model II.

ST

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