Direct Mode vs. Stereo Mode vs. Tone Control or HPF On/Off - Detailed Test
I have been conducting tests on the effect of switching between Direct and Stereo modes with Tone Controls or HPF On/Off on my Denon AVR-2310. All tests done with music on my L/R Front B&W 804 Diamonds.
Below are the results of my tests:
Case 1 - Direct Mode
First of all let me state that across all the cases, the bass response of my speakers was very similar, only minor differences can be noticed. The major differences can be noticed through the midrange and tweeter responses of the 804 Diamonds.
In Direct mode, the human vocals seem to be coming from a higher vertical position (compared to Stereo Mode with Tone Controls and/or HPF on), somewhere between the midrange FST cone and the tweeter. Also, the human vocals are separated; I can hear the sound coming from the left and the right while the left channel seems to be louder than the right one. I think the latter observation may be arising from the fact that the Direct mode doesn't apply distance adjustments to speakers as my left speaker is closer to my listening position than my right one (3.4m versus 3.7m). I have used extreme distance adjustments to verify this (added 5m to the right channel) and I could not hear any difference. This confirms, at least for my model, that the Denon skipped the distance adjustments in Direct Mode. However, the level adjustments are still functional and the level of each channel (L/R) can be adjusted separately.
When it comes to HF, the tweeter response was smoother and less focused than with Stereo Mode with Tone Controls or HPF On.
Case 2 - Stereo Mode with Tone Controls set to Off and HPF set to Off (Front Speakers set to Large)
Exactly the same sound as in Direct Mode except for the observation of the left channel being higher than the right channel issue in Case 1. In Case 2, the vocals seem to be of the same volume from the F/L speakers. This indicates that the distance adjustments are applied in the Stereo Mode.
Again, the sound is exactly the same as in Direct Mode: same Midrange and same High Frequencies as Case 1.
Case 3 - Stereo Mode with Tone Controls set to On and/or HPF set to On (setting Front Speakers to Small)
Now this is the most strange case. Once you are in Stereo Mode and you activate Tone Controls (with both Bass and Treble set to 0 dB) and/or you activate the HPF by setting the Front F/L speakers to Small (regardless of the crossover frequency, be it 40 Hz, 60 Hz, 80 Hz, or 90 Hz) something very strange occurs: the human vocals suddenly drop in height to somewhere between the two bass woofers (around 40 cm or 16 inches drop from Cases 1 and 2). Also, after the vocals were previously separated between the left and right channels in Case 1 and Case 2, now the vocals, violins, and flutes (Midrange in general) become very focused and appear to be coming exactly from the middle of the distance between the two front speakers. It is as if the singer is standing exactly in the middle of the room in front of me.
Also, the HFs become harsher and more focused as well. Sometimes they sound unpleasant and a little harsh but very clear, clearer than Cases 1 and 2.
Apparently, switching on any circuitry to digitally processes the sound (be it the Tone Controls or the HPF) affects the sound in this strange manner described in Case 3. I am saying strange because it is not worse, actually I feel that the focused midranges from the middle of the room along with the drop in height sound more realistic than Direct Mode in Case 1 or Stereo mode in Case 2. I actually like the sound coming from the middle than being separated in Cases 1 and 2.
I hope this test above prove beneficial to whoever is reading it. I am also very interested to know if anyone has experienced such differences in their systems before.
Waiting for your feedback.
7.1 system consists of the following:
B&W 804 Di Front Speakers, B&W CM Centre 2 Centre Speaker, B&W 685 L&R Surround Speakers, Bose 301 V Rear Surround Speakers, B&W DB1 Subwoofer, Denon AVR-2310 7.1 used as a Preamp, Marantz MM7055 Amplifier, HRT Music Streamer II+ DAC as Source
Last edited by Shebs80; 06-27-2014 at 12:16 PM.