Descent sub crossover setting

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htsource

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Hi,

I'm finding I get too much bass at 80Hz which is the crossover point from my processor. I have Aeon as fronts.

I was told I could try setting the crossover in the processor to 100Hz, and set the sub to 80Hz. However, I don't think I can adjust the crossover on the Descent? I believe it's fixed to 40Hz or 70Hz? Also, with the sub out, I believe the internal crossover is disabled?

Or do you have any other suggestions?

Thanks,
Simon
 
htsource said:
Hi,

I'm finding I get too much bass at 80Hz which is the crossover point from my processor. I have Aeon as fronts.

I was told I could try setting the crossover in the processor to 100Hz, and set the sub to 80Hz. However, I don't think I can adjust the crossover on the Descent? I believe it's fixed to 40Hz or 70Hz? Also, with the sub out, I believe the internal crossover is disabled?

Or do you have any other suggestions?

Thanks,
Simon
Hola Simon...in the speaker's config setting at the receiver, choose small speaker for the Aeon and then you can use 80Hz with no problem...if you have too much bass, you could bring the level down at the sub to match the Aeons bass. Hope this can help...happy listening,
Pura vida,
Roberto
 
Hi Roberto,

Thanks for your reply, the only thing is I only get too much bass in the 80Hz range so I was hoping to do something that will only affect 80Hz.

The speaker setting is set to small for the Aeons.

Thanks,
Simon
 
htsource said:
Hi Roberto,

Thanks for your reply, the only thing is I only get too much bass in the 80Hz range so I was hoping to do something that will only affect 80Hz.

The speaker setting is set to small for the Aeons.

Thanks,
Simon
O.K...what you have is a peak resonance at that particular frequency...it is due to your room and your sub placement, and they are called standing waves, sometimes what you need to do is to move your sub away from the back wall, and try to find a place in the room where it does not resonates at that frequency. Remember that the low frequency does not have direction...this means, we don't hear it from where it comes, unless it is above around 100Hz, where we do. So you can move the sub from left to right, until finding a point where it does not interacts as much with the room, or finding a different location that will not interfiere with your furnitures. Sometimes :D it is a difficult task, but not impossible. Trust your ears...and I wish you a happy listening,
Pura vida,
Roberto.
 
roberto said:
So you can move the sub from left to right, until finding a point where it does not interacts as much with the room, or finding a different location that will not interfiere with your furnitures. Sometimes :D it is a difficult task, but not impossible.

a trick i heard about is to put the sub where you sit and you walk around the room until you find the spot where the sub sounds best. then you put the sub there (and free up the other spot for you to sit :) )

you might also consider a parametric equalizer. i once had a room with a mild 55Hz hump. it was darn easy to find exactly what was what with a sweep frequency generator, and at that point a PE could have been used to tweek out that particular hump.

cheerslance
 
zaphod said:
a trick i heard about is to put the sub where you sit and you walk around the room until you find the spot where the sub sounds best. then you put the sub there (and free up the other spot for you to sit :) )

you might also consider a parametric equalizer. i once had a room with a mild 55Hz hump. it was darn easy to find exactly what was what with a sweep frequency generator, and at that point a PE could have been used to tweek out that particular hump.

cheerslance
Hola Zaphod. Yes, that's a very good trick. Both are great suggestions!..remember, trust your ears, happy listening,
Pura vida,
Roberto.
 
Descent adjustment...

htsource,

I agree with Roberto. If you have hooked up your Descent to LFE in-put and your Descent is set at 70 Hz, I would agree that Descent placement maybe your next adjustment. My Descent is almost in the center of my HT. As you probably know bass sound waves are very long and they need room to expand, with Descent's tri-force, three ten inch alumium speaker array - firing in three directions at once, positioning is key. IMHO, be patient and you will find what does sound good to your ears... :D You should also consider the Subwoofer Management System (SMS-1) by Velodyne Check this out:

http://www.martinloganowners.com/forum/showthread.php?t=1169&highlight=SMS-1

If I had the extra cash I'd buy a SMS-1 too. :eek:

HTH
 
If playing with placement does not work consider room treatment. Inexpensive but effective solutions are available from eighth nerve, room tunes or asc. I cured a similar problem in my HT system with an Outlaw Audio ICBM ANALOGUE bass manager-$250 bucks off their website and sounds like $2500! Without a doubt the biggest bang for the buck improvement I ever made to my HT system.
 
Thank you for all the valuable information, I'll try the placement but the room and furniture layout pretty much dicates where the sub goes :(

Can't afford the SMS-1 now but what do you think of the Behringer BFD? It seems getting good feedback of what it does and how much it improves how the sub sounds. I can probably afford one if it's that good!

Thanks,
Simon
 
I posted this in the Off Topic forum awhile back: it's a free Java-based room analyzer for a PC/Mac with sound input that you couple to an inexpensive RadioShack SPL meter (be sure to download the compensation tables for that meter). It will help find room resonances and will plot the inverse equalization curve so you know how and where to tweak your prepro's equalizer, assuming it has one. The software directly supports the Behringer Feedback Destroyer.

http://homepage.ntlworld.com/john.mulcahy/roomeq/index.html

If you like the software, the author does accept, but does not require donations.
 
Hi guys,

I'm making progress here. I got an used BFD 1100P which is an older model but it works great. I've attached the graph from before and after. BLUE is before applying the EQ. Pink is after the EQ is engaged.

I'm stilling learning about the bandwidth and how wide or narrow the bandwidth should be to obtain a nice smooth curve.

Sound is so much smoother with music, I'll need to play a movie tomorrow to see how it sounds.

If you guys have any tips to smooth up the curve, let me know. Thanks,

****** THE ATTACHMENT IS GIF BUT THE FORUM WILL NOT ALLOW ME TO UPLOAD. PLEASE CHANGE THE EXTENSION FROM .ZIP to .GIF AND IT SHOULD OPEN.

Simon
 

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