New Custom Cabinets for LE14H-3, 2452H-SL and PT-F95HF

[Robh3606]

Look great!

Rob

[Duffinator]

Look great!

I checked out the pictures over at AK, but I didn’t read the thread... so, how do they sound? Would Zilch be proud?


Widget

Zilch would love the cabinets. My friend really put in a lot of work on the cabinets and they are perfect to my eye.

Zilch came to my house to listen to my V1.5 of the speakers and thought the bass was "overwrought" and suggested playing with plugging the ports which I did. They are in a small 10x11 room that's fairly active. This is probably a self fulfilling prophecy but the new cabinets improved on some of the concerns I had before with the highly resonate Barzilay cabinets. Mainly that the highs and mids are more focused and clear. The overall clarity was improved. What they didn't really improve on was the boominess I hear when I crank up the volume. I think some of this is the room but not all. With my Barzilay cabinets I had the ports front facing. I'm using one 4" port in the back now (Think S4600) and the speakers are very close to the wall. It's just a small room and there's not much I can do about it. I bought some foam and will play with plugging the port completely and also using plugs with holes in them to see if I can tame them a bit.

[Ian Mackenzie]

Try a foam plug.

Alternatively tune the ports a bit lower so the port output is less aggressive.

Failing that you could try a tone control function like this

https://www.schiit.com/public/upload...s%20manual.pdf

Or a more sophisticated room correction like used in a home theatre amplifier. Nad make some nice equipment with Dirac that would settle the bass issue to a large extent.

https://nadelectronics.com/dirac-live/

[Duffinator]

Try a foam plug.

Alternatively tune the ports a bit lower so the port output is less aggressive.

Thanks. So tune the port lower not higher? I cut different length of the tube to attach to the flare so I can easily do that.

[Robh3606]

Thanks. So tune the port lower not higher? I cut different length of the tube to attach to the flare so I can easily do that.

Tuning lower extends the bass and reduces output. Like Greg's banana curve.

It depends on what frequency the "room" bump is. If it in the low range say 60Hz or so it might help by reducing output there. If it's above say 100-150hz and up it won't.

Also depends on the Q of the mode. Really high Q hard to fix without actually moving the speakers. If you do extend it make sure you leave enough room so it's not too close the the rear cabinet wall.

What are you tuned to now??

Rob

[Ian Mackenzie]

Thanks. So tune the port lower not higher? I cut different length of the tube to attach to the flare so I can easily do that.

Yes. Try the plugs first as it’s then like a sealed enclosure.

[Duffinator]

They are tuned to 35 hz. I'll try the plugs first. Thanks for the suggestions.

[Ian Mackenzie]

See how it goes.

In theory the axial room modes with the walls are 56 hertz and 51 hertz and then X2 those frequencies. The room is close to square so that will tend to excite those two lower frequencies above all else.

[Dr.db]

As Ian has just mentioned, your room is nearly square so both room-modes kind of double up. Subjektivly you have ONE major peak.

Maybe a Helmholz-Resonator tuned to those specific frequencies is an option?

[Duffinator]

It seems like it's a very specific frequency low but not too low.

[Mr. Widget]

It seems like it's a very specific frequency low but not too low.

In my last listening room (living room), I had a nasty room mode that really clouded the bass and made my system disappointing with many tunes. I eventually isolated the mode by using Studio 6 Digital’s app called Larsa.

With Larsa I was able to isolate the peak and tame it with a high Q cut filter... all of a sudden my music library expanded and my satisfaction level went off the charts.


Widget

[Ian Mackenzie]

I would still try the port plug and see if it helps.

[Dr.db]

I would still try the port plug and see if it helps.

Me too!
Definitly try this first, as it doesn´t cost anything and may be sufficient.


In case you would like to tackle this problem further, there are basically two ways you can go.
Active filtering of the proplematic frequencies with a sharp notch filter as Widget suggested.
Or by using room-acoustik modules like helmholtz-resonators or membrane-absorbers.

GIK offers custom tuned membrane absorbers. You would have to measure the exact room-modes first, but that would be a great solution. Mind that you will need more than one modul, propably aprox. 4-8...
https://www.gikacoustics.com/product...bass-trap-t40/