Interesting discovery - receiver "modes"

[lovingdvd]

Well it had been driving me nuts for a while as to why my receiver seemed to be putting out more bass in the mains than it should (playing bass considerably higher than where it should be crossed over).

I'm still experimenting, but it looks like the issue is that I had one of the Yamaha programmed effects mode engaged.

For instance out of the various modes I've always seemed to play movies in the "Adventure" mode. This apparently adds a +8dB boost to around 30hz among other things. When your speakers are crossed over at 80hz this of course can provide for some surprisingly wrong results!

With hindsight this is quite logical. However it hadn't dawned on me and was the source of much confusion for the first couple of days until I finally discovered this.

I have a bit more playing to do before I can report something more concrete. But preliminarily it looks like calibration should be done in what they call "Straight" mode which means the receiver doesn't apply any of its fancy "effects".

With this in mind I think it would be very helpful for beginners if information was added to the Help File for the setup/getting started that recommended you turn off any such effects - or may just to make people aware that such listening modes may result in unexpected differences in dB levels vs. the typical target curve.

[Wayne A. Pflughaupt]

lovingdvd wrote:

For instance out of the various modes I've always seemed to play movies in the "Adventure" mode. This apparently adds a +8dB boost to around 30hz among other things. When your speakers are crossed over at 80hz this of course can provide for some surprisingly wrong results!

Wow, no kidding? Never knew that. I typically use the “Adventure” mode for movies, too.

With hindsight this is quite logical. I have a bit more playing to do before I can report something more concrete. But preliminarily it looks like calibration should be done in what they call "Straight" mode which means the receiver doesn't apply any of its fancy "effects".

Yup. My older model has an “Effects Off” switch on the remote, to turn off the DSP effects.

Regards,
Wayne

[lovingdvd]

After playing with things some more this evening I can say with 100% confidence that the DSP effects definitely mess with the bass considerably.

In particular the "Adventure" mode adds a large peak in the 30s and another in the 60s - even with the xo set at 80hz! Even their "normal" basic surround mode lowers the overall dB of the bass and adds a hump from 20-30hz. Interestingly for those without REW/BFD or similar tools this mode would serve as a great poor mans house curve tool!

So after several days of mucking about without great results (because my bass was always too high coming out of the mains despite the xo) this discovery enabled me to tackle the sub and get the exact house curve I wanted by using the "Straight" mode.

I wound up with a totally flat response (when I use the 1/3 octave option in the graph) along a custom house curve of +8dB at 20hz to 0dB at 80hz with both the sub and mains playing.

It really sounds amazing. I'm not positive but I think I have it balanced around the point were the middle of the range is about 75dB - so it runs hot on the low end and a little quiet on the high end. I had it pushing things a bit hotter but after some preliminary listening it was bordering on being a bit too boomy at that point.

The only real down side is that I liked what the "Adventure" mode did for voices - just gave them a bit more clarity and "snap". However I cannot use that mode as it really destroys the sub curve. I think that I have a -15dB dip around 300hz when running in Straight which is not present in Adventure which may be causing this. Any ideas on how to handle this?

For reference I have the Yamaha RX-V1400.

[lovingdvd]

BTW - I meant to add that I believe I have plenty of headroom and so forth for the +8dB house curve. The volume input on my BDF is set properly, and the sub amp is just a quarter turn from the minimum. Also as much as I tried I couldn't avoid adding on gain in the filters which was a +2dB gain at 20hz with a bandwidth of 2.

Its a 250w sub and a 110w receiver powering the rest of the system. When I play at the loudest level I would ever listen to the system at everything sounds good including the deepest bass parts.

That being said, is there any way to verify that indeed I am not clipping and have the proper heard room for this setup? Thanks.

[brucek]

The volume input on my BDF is set properly, and the sub amp is just a quarter turn from the minimum

I think you can be confident that you're not clipping your sub..

brucek

[Malice]

You can also add another dimension to this for Denon amps that also carry out their own EQ. But as this can be turned off or to one of 4 settings (Normal, Front, Flat, Manual) it isn't any issue.

However, I had been struggling with finding a mode which had no DSP effects applied as there doesn't appear to be an option to defeat DSP other than Direct or Pure Direct.However, from I could determine from plotting the mains in these modes, the crossover filter is not applied. I'll double check again but I think this is the case. In which case I'm not sure which "DSP" mode I should use from which I can EQ the sub.

[Wayne A. Pflughaupt]

Maybe the one you would use the most for movies, and a separate BFD program setting for the one you use most for music?

I had a similar experience yesterday when I was doing some testing with 1/12-octave sine waves. (I have a Yamaha, like lovingdvd has.)

Between two passes I played some music, and when I started the second pass I forgot to turn off the DSP, which was “Cellar Club.” This one has always been my favorite for music. I did unplug the front speakers, though, ‘cause I didn’t want the mains mixed in with it.

Well, when I got to 47 Hz, I was getting a huge suckout, more than 10 dB!

Pretty strange. With the speakers set to “small,” the rear speakers (which were the only ones still connected) should be doing virtually nothing! The problem might be that I’m using my main pre-outputs to an external crossover instead of the subwoofer outs. Maybe I need to change that. However, my Yamaha has a switch on the back that lets you opt to eliminate any DSP processing to the main speakers, so there shouldn’t be anything happening from the main output jacks with the DSP turned on.

Regards,
Wayne

[Malice]

Wayne A. Pflughaupt wrote:

Maybe the one you would use the most for movies, and a separate BFD program setting for the one you use most for music?

For movies though the amp usually goes into Dolby Digital EX (7.1) or DTS ES, and as you know pushing through an analogue signal will put the amp into another mode, in my case Dolby Prologic PLIIx. Perhaps "plain" stereo mode is an option to plump for for EQ'ing. Dunno.

[lovingdvd]

That will be a real pickle if your receiver doesn't cross over anything with the sub set to "straight" or "pure" or whatever you call it. In the case of the Yamaha, fortunately, when used in "straight" it does cross it over and also still applies the PEQ. Although I used Adventure for years I now find that with "straight" and my sub set correctly that my sound is much more crisp and defined. The Adventure mode was putting way too much bass to the mains which was limiting its ability to produce super clean mids and highs and driving the receiver amp more than it should (basically was defeating me setting the speakers to Small).

[Malice]

There's a Denon guru over on AVForums who advises using the "Stereo" mode, which TBH I thought was probably the best option as it does apply bass management but apparently nothing else.

[cyberbri]

I use 2-channel stereo with bass management for regular CDs.

The sound modes do do different things with the bass and other frequencies.

Ie., after eq'ing my sub and calibrating it 2~3dB hot for movies and 0~1dB hot for music, I use Avia to set the mains, center and sub level for DPLII, Logic 7, and DTS-Neo.

I was watching Battlestar Galactica a few weeks ago, on cable, using DPLII Movie. Some of the male voices were coming through the sub pretty strongly. This *never* happens with DVDs or shows in DD/DTS. I lowered the xo setting from 80Hz and that helped a bit. But you can tell that the different sound modes handle bass and all the other DSP effects on the sound field differently.

Even for music, DPLII, Logic 7, and DTS-NEO can do some interesting things. But it's usually hit and miss for me, as far as how good it sounds. Sometimes one of the modes will sound good with one song, but bad with another. So I just stick with good ol' stereo and bass management, no DSPs. I only use DPLII movie/music if I'm watching a TV show that was encoded for Dolby PL surround and meant to be decoded into one of those modes.

[Hakka]

Malice wrote:

There's a Denon guru over on AVForums who advises using the "Stereo" mode, which TBH I thought was probably the best option as it does apply bass management but apparently nothing else.

The stereo mode on the Denons is the way to go if you want to run your mains as small, direct and pure direct will run the mains as large regardless of their size setting.


Here's a graph of stereo(red) vs direct(blue) on my 3803 using both mains and both subs.

[Malice]

It became even clearer when I had speakers set to small, XO at 80Hz, switched off the sub and ran a sweep via Direct (even though the XO was at 80Hz) and then a series of XO via the Stereo.

Graph shows for MAINS only:
Direct
40Hz XO
60Hz XO
80Hz XO
100Hz XO

Interesting that with room gain my mains are producing more or less target level output (75db) at less than 30Hz on a crossover of 60Hz. But there is quite a dip in the all importnat 40Hz region!