Descent back in for 2ch

[timm]

Well - after about a year of listening to my odysseys without my descent - I got crazy and decided to move it back into my 2 channel setup again. The diff this time is this: I have come to the concluson that all I really want from the descent is just a little itty bit of low end... I don't need to hear it - if that makes sense.... I turned the volume on it down just a touch (1 number) - and just bumped up the 25Hz up a little. What I have seemed to have found is - no muddizness in panels -- a little bit more warmth - music sounds a little more 'whole' and not necessarily as clinical. My descent is in a corner about 6" to 12" off of the corner walls... I am trying to avoid boom - but there is really no other place to put the sub.

Anyone have their sub out of the corner and away from walls?

Anyway - anyone with a sub - have you gone back and forth with this? If you left it in - what was your winning combination for 2 channel listening?

 

[tonepub]

The front panel of my Descent i is about 36" from the back wall and about 50" from the side wall. I ran the Summits (and now Spires) full range with the crossover set at 270 deg. and the crossover frequency at 35hz.

In my room, I have a slight bump (+2db) on the 25hz control and the 50hz is set to 0, but this will be completely different in your room.

When I was using a REL sub, they also said that you got the best quality of bass, by having a full range main system and letting the sub only take care of the very lowest frequencies. When I had the REL, I had it crossed to the Summits at 27hz.

Here's one other tip if you are interested, the Audioquest SUB-3 subwoofer cable. We've got a full review this issue, but Harvey Gilbert from MartinLogan turned me on to this and it made a HUGE difference in terms of getting a lot more definition from the Descent (and every other sub I plugged it in to).

Depending on if you are using one cable or two to connect up to the Descent, they cost between about 250 and 430 each, depending on length.
If you don't have a dealer that will let you borrow a set, Music Direct offers a 15 day money back policy.

This is the biggest improvement I've yet to make to a subwoofer setup!

 

[ScottGardner]

I have come to the concluson that all I really want from the descent is just a little itty bit of low end... I don't need to hear it - if that makes sense....

Makes perfect sense. Generally this is the preferred way to do it. You should be able to feel it without hearing it.

anyone have their sub out of the corner and away from walls?

Anyway - anyone with a sub - have you gone back and forth with this? If you left it in - what was your winning combination for 2 channel listening?

I have a Mirage BPS 400, bipolar 2 12". I have had it all over the place and currently have pushed tight into the corner (one speaker directly on to the side wall and one speaker firing across the back wall). This speaker can be boomy but this arrangement seems to work best in that regard. It is also somewhat sluggish but if the main speakers are slightly delayed it helps a lot. In my experience getting the sub right is proly more difficult than anything else; however, in my case this is largely due the Mirage itself.

 

[nsgarch]

Anyone have their sub out of the corner and away from walls? Anyway - anyone with a sub - have you gone back and forth with this? If you left it in - what was your winning combination for 2 channel listening?

Before you make yourself crazy over cables, and room response problems etc, etc, do this (if you possibly can):
1. Place the sub exactly in between the main speakers, and exactly even with the panels (front to back.)
2. Set the phase angle to 90 degrees (that's the phase angle of the sound wave halfway between the front and back of the panels)
3. Set the x-over point to 25 or 30Hz. The Odyssey bass response essentially disappears by 35Hz, so combining the sub starting to fall off (as the freq goes above 35) with the mains starting to fall off (as the freq. goes below 45) makes a fairly straight line response across the sub/main interface.
4. Turn the 25Hz boost off at first and just turn up the main level on the sub until you can barely notice a difference if you turn it off -- that's the 'right' level (at least for your setup recording )
5. The 25Hz boost is nice if you need it. If you can already feel strong bass drum or tympani in your gut at moderate levels, you don't need it. Otherwise increase the boost until you can barely notice it, and then cut it back a tick.

Now, about those cables :ROFL:

 

[timm]

Thanks guys...

Yes - the first time I heard the descent it was perched between two ascents... It sounded fantastic. I could move mine there for testing purposes - but it wouldn't work well in the long haul because it would be right in front of my equipment... but it might be fun to try....

Tonepub -- I currently have an audioquest sub cable -- can't remember any particular name - but it was not that expensive and is blue... It looks like the sidewinder - but I think it is called something else now...

I have an original descent - so my x-over points are 40 or 70... I have mine set to 40... I don't know what it is - but I do not hear much - if any difference by manipulating the phase.... It is currently @ 90....I do believe.

The oddyseys are basically 5-6 feet from the front wall - and the sub sits behind the right speaker slightly to the right - in the corner.....

 

[nsgarch]

Thanks guys...Yes - the first time I heard the descent it was perched between two ascents... It sounded fantastic. I could move mine there for testing purposes - but it wouldn't work well in the long haul because it would be right in front of my equipment... but it might be fun to try....

If you look at my system pic, you'll see that my Depth sits on the bottom shelf of my rack but here's another trick, it just takes time and patience:

Replace (temporarily of course) your listening chair/couch with your sub. Then move about the room until you find the location(s) with the cleanest bass. Then refine the subs's settings for those two or three locations, setting the sub to different phase angles, crossover points and levels for each of the listening positions (ie, future posible sub locations.)

This is also when 'audio friends' come in handy ;-)

 

[amey01]

I've got mine well away from the corner. I use a Behringer DSP1124P for EQ though. I figure I can't really tell the difference with it in or out - I'm talking about 35Hz and under and the volume is also set very low. But I can definitely tell when it is on or not - something is missing if it is off!

 

[ScottGardner]

Replace (temporarily of course) your listening chair/couch with your sub. Then move about the room until you find the location(s) with the cleanest bass. Then refine the subs's settings for those two or three locations, setting the sub to different phase angles, crossover points and levels for each of the listening positions (ie, future posible sub locations.)

This is also when 'audio friends' come in handy ;-)

Yes, this is the popular school of thought.

Here is another that may work better in some cases: http://www.sonicdesign.se/subplace.html

A short excerpt...

...[the popular] method has been cherished in most HiFi magazines, but it has several weaknesses that might be helpful to know.

1. It is not at all certain that what is appointed, almost axiomatically, "the best listening position" in the first phase of the experiment, is really the best. It may even be a disastrous listening place, where bass of good quality is almost impossible to get...

 

[RichTeer]

Anyone have their sub out of the corner and away from walls?

For clean bass, out of the corner and away from walls is the only really correct placement for subs. Alas, domestic harmony tends to intrude!

 

[tonepub]

Before you make yourself crazy over cables, and room response problems etc, etc, do this (if you possibly can):
1. Place the sub exactly in between the main speakers, and exactly even with the panels (front to back.)
2. Set the phase angle to 90 degrees (that's the phase angle of the sound wave halfway between the front and back of the panels)
3. Set the x-over point to 25 or 30Hz. The Odyssey bass response essentially disappears by 35Hz, so combining the sub starting to fall off (as the freq goes above 35) with the mains starting to fall off (as the freq. goes below 45) makes a fairly straight line response across the sub/main interface.
4. Turn the 25Hz boost off at first and just turn up the main level on the sub until you can barely notice a difference if you turn it off -- that's the 'right' level (at least for your setup recording )
5. The 25Hz boost is nice if you need it. If you can already feel strong bass drum or tympani in your gut at moderate levels, you don't need it. Otherwise increase the boost until you can barely notice it, and then cut it back a tick.

Now, about those cables :ROFL:

Yeah and while you put the sub in the exact middle of the room, put it right in your equipment rack... I'm sure there won't be any standing waves there.

All that vibration is really good for your amplifier, especially if it has tubes.
:ROFL:

And if none of that works, you can actually get a set of test tones and a meter to MEASURE where to set everything. The level controls are much more suited to adjusting for your room issues, not as a tone control.

If you can take the time to measure where the bumps are, chances are good you can make most of the adjustments by moving the sub, not playing with the level controls that much. Laugh all you want about the cables, I did too until I actually TRIED it.

 

[ScottGardner]

For clean bass, out of the corner and away from walls is the only really correct placement for subs. Alas, domestic harmony tends to intrude!

I'm sorry dood, I guess I'm just a radical at heart. Here's another excerpt from the above link:

A corner placement gives lower distortion!

An interesting side effect of placing the subwoofer in a corner is that the distortion is lowered significantly. The cause for this is that you get a reinforcement of fundamental tones from all the reflections in phase from the adjacent surfaces, while harmonics (which is distortion when it comes to a steeply low pass filtered subwoofer) are lacking the corner support, and become weaker in amplitude compared to the wanted fundamentals. In addition, you also get increased efficiency which means that the input power to the subwoofer can be decreased, which also contributes to less distortion and increased headroom. There are many good reasons to consider a corner placement if you have only one subwoofer.

 

[preston]

REW software or similar

Hi Timm:

You should check out the REW software, which is free on www.hometheatershack.com. This could make a huge difference in your audio experience

REW helped me to identify room issues (nodes & peaks) and deal with them principally via placement (then equalization)

I still have a small node at about 55hz which is a problem with my room that I can do nothing about (nodes are often considered less problematics and less audible than peaks). Without REW, you do not know where your peaks and nodes are and how to deal with them. Without REW you do not know the ideal crossover of your mains as placed in your room either

Conclusion: My sub is now very well integrated with my mains and completely disappears into the sound. System sounded OK before using REW software, now sounds great

 

[SteveInNC]

I solved the "center of the room" problem by getting a second Depth. They're positioned next to each Ascent i. I'm also running Audyssey to compensate for room nodes. I leave the Depths on for both two-channel and HT. They fill in the low range for two-channel, much like you described: you feel them more than hear them, but it also adds punch to the low end.

 

[timm]

Hi Timm:

You should check out the REW software, which is free on www.hometheatershack.com. This could make a huge difference in your audio experience

REW helped me to identify room issues (nodes & peaks) and deal with them principally via placement (then equalization)

I still have a small node at about 55hz which is a problem with my room that I can do nothing about (nodes are often considered less problematics and less audible than peaks). Without REW, you do not know where your peaks and nodes are and how to deal with them. Without REW you do not know the ideal crossover of your mains as placed in your room either

Conclusion: My sub is now very well integrated with my mains and completely disappears into the sound. System sounded OK before using REW software, now sounds great

Curious -- can you give me an idea of how this works? I'll take a look at the docs --

 

[timm]

Curious -- can you give me an idea of how this works? I'll take a look at the docs --

oh - just took a look .. lots of problems for me -- would need to buy some stuff .. move my computer etc....

 

[nsgarch]

No problem, Mr. Fact-checker

Yeah and while you put the sub in the exact middle of the room, put it right in your equipment rack... I'm sure there won't be any standing waves there. All that vibration is really good for your amplifier, especially if it has tubes..

http://www.martinloganowners.com/forum/showpost.php?p=18777&postcount=12

 

[MOON]

Hi Timm,

I have Odyessey's as well as a depth sub. I initally put the sub between my Odyssey's which are 5ft off the back wall and found that the bass was very clean in that position and was seamless. I moved it to the side wall , just past the speaker by about a foot and a half and found the bass seemed to not integrate as it had in the center position and wasn't as clean.

I have had my system down for a day to apply caig pro gold to everthing that needs it and will take this opportunity to reposition the sub back to the center postion where it sounded the best.

ns garch - Thanks for the tips , which I will try out

Cheers

 

[tonepub]

Every room will have different peaks and dips in the bass response, due to the room size, ceiling height, whatever furniture you have, etc etc. so the optimal spot in every room is going to be a little bit different for everyone.

I think Ethan will back me up on this.

While not terribly precise, you can get a rough idea of room issues with a simple test tone CD. You should be able to hear where the rough spots are by listening to tones from about 100 hz down to 20.

If you want to go further and get a level meter or even further with some software and a calibrated mic, you will be surprised at how much you can improve the bass response of your system just by moving your speakers and subwoofer around...

 

[timm]

Hi Timm,

I have Odyessey's as well as a depth sub. I initally put the sub between my Odyssey's which are 5ft off the back wall and found that the bass was very clean in that position and was seamless. I moved it to the side wall , just past the speaker by about a foot and a half and found the bass seemed to not integrate as it had in the center position and wasn't as clean.

I have had my system down for a day to apply caig pro gold to everthing that needs it and will take this opportunity to reposition the sub back to the center postion where it sounded the best.

ns garch - Thanks for the tips , which I will try out

Cheers

Moon - thx for the info... Maybe I will lug it over there to give a listen... But, to me - it seems like that would be an optimal place for stereo listening...
Nice to hear someone else's experience w/odysseys etc... What are your x-over settings on your Depth?

All of my critical listening is in 2 channel -- but last night - I watched a movie - and that thing rocked the house. This is at the 40hz x-over point. The good part is that ican rock the house with a movie - but still get fairly smooth integration with stereo without changing any settings.

 

[timm]

Moon - thx for the info... Maybe I will lug it over there to give a listen... But, to me - it seems like that would be an optimal place for stereo listening...
Nice to hear someone else's experience w/odysseys etc... What are your x-over settings on your Depth?

All of my critical listening is in 2 channel -- but last night - I watched a movie - and that thing rocked the house. This is at the 40hz x-over point. The good part is that ican rock the house with a movie - but still get fairly smooth integration with stereo without changing any settings.

Hi all - just wanted to respond back on this -- it has been 2 weeks - and I did move my descent into the middle between my odysseys. My brother (he has ascents) came from chicago and got a chance to listen with & without it as well... The verdict is - the descent is staying in the middle. I was not using it for 2 channel - (as a recap) - but have found that by moving it out of the corner I could blend it very easily. I have the level on fairly low - but, it makes a difference without making a difference - if you know what I mean. I still think the Odysseys sound great without it .... just better with it.

I think putting the sub in the corner gives better output - but it is just impossible to blend well with the mains which gives a 'tubbier' & slower sound. Great for bombs - not necessarily so great for music...