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(Balanced, with high pass filter) Sub for Genelec 8040B, how?

_Dekker

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Not too long ago I upgraded from M-Audio Cx-5 monitors to Genelec 8040B's.
Reason was to get more low end and better quality sound overall which was a total success: I simply love them.
However I'm now enjoying the additional low bass (30Hz in room) so much that I'm looking towards a future subwoofer addition to get the extension to 17-20Hz.
(The 30Hz I have now is achieved by a slight 2-3dB boost in the low end to get the level up sufficiently so that is not really optimal for quality bass.)

Setup is:
Windows PC running Equalizer APO
Monitors: Genelec 8040B
DAC: Soncoz LA-QXD1 (balanced connected to monitors)
HP amplifier: Massdrop THX AAA 789 (it has a single ended passthrough available)
UMIK-1 which I used to calibrate the low end

So what am I looking for:
A- At least extension down to 17-20Hz
B- Balanced connections since I have ground loop issues without.
C- Compact size
D- Budget max 1000euro
E- Available in Europe

Genelec 7360A is the one that should fit best but it is double the budget I'm willing to spend.
Also the size of the 7360A is already making me cringe, it is quite huge already.
Since the THX 789 has a passthrough I thought I might be able to use that to go to a sub but I do not know if I re-introduce ground loops that way.
Also the 8040B's do not have a high pass filter, so I will have no proper control over crossover if the sub does not have a high-pass filter.

Subs that I really like are:
Arendal 1961 1s
Monolith 10in THX

But the crossover (and ground loop?) issue seems to make them impossible..
I hope there is a solution for me..
 

NTK

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The Dynaudio 18S is over your budget too, but the 9S doesn't seems to go low enough for you.
 
OP
_Dekker

_Dekker

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I found the big subwoofer overview spreadsheet (totally missed it earlier) and had a play with it.
Another constraint I put on myself is to use a closed sub in order to get maximum low-end extension with room gain.
Also the compact size requirement is easier to meet with a closed box.
With this it looks like the only options for me are, but a bit out of budget:
Dynaudio 18s (totally forgot about it, thanks!)
Neumann KH750
SVS SB12-Plus (discontinued)

If I'm correct with the Neumann there are additional A/D/A conversions in the sub when going DAC --> KH750 --> Analog Genelecs. I'd rather avoid that. But reqarding looks & durability the Neumann probably is the one to get..

So looks like the Dynaudio 18s is the only one remaining for my wishes. I'll need to keep on saving then.
 
OP
_Dekker

_Dekker

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Update:
I managed to get a nice deal on a new Dynaudio 18s Sub and I am just now finished with installing it.
Balanced cables go to the sub and then balanced again from sub to the monitors (Genelec 8040B).

Most difficult part was finding a nice spot for the 18s, the first location on the desk had a absolutely massive dip at 50Hz.
By moving around I found a perfect spot behind me, on the floor next to the left side wall.
I had to tame the massive room gain down by adding a -12dB (!) notch filter right at 20Hz.
Btw to get the bass right you absolutely need a mic, no way you can do this without.
I simply activated the HPF in the 18s which is only available for 80Hz. But works perfectly.
Also activated the LPF at 80Hz (24dB/Octave) (here lots of other frequencies available in 10Hz steps.)
Then entered the distances of all speakers to the listener position. In my case 90cm for the monitors and 140cm for the Sub. This is a very nice feature, I'm not sure but I think before adjusting this the sound was not as tight as it is now.
Attached the in room response, averaged. Within a 30cm box the response does not change up to 350Hz.

It sounds awesome, a lot of tracks get more body to it, even though the setup without sub already went down to 35Hz.
Everything lower than the 35Hz sounds so natural and effortless, I love it.
I do not think a Genelec sub could have done it better than this.

Some minor things that I noticed:
Firmware flash to new version was extremely fast. The manual stated 1-3min but is was more like 3 seconds.
The firmware on the sub did not have the HPF setting but the newest firmware (V004.0011) on the Dynaudio site has it.
There is increased tweeter hiss from the monitors by connecting them to the 18s. Before I could not hear the tweeter hiss at all but now when the room is quiet it is noticable.
I noticed that entering the distances in the Sub would give a loud pop when entering the value. Better to turn off the monitors before doing this.
 

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YSC

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Update:
I managed to get a nice deal on a new Dynaudio 18s Sub and I am just now finished with installing it.
Balanced cables go to the sub and then balanced again from sub to the monitors (Genelec 8040B).

Most difficult part was finding a nice spot for the 18s, the first location on the desk had a absolutely massive dip at 50Hz.
By moving around I found a perfect spot behind me, on the floor next to the left side wall.
I had to tame the massive room gain down by adding a -12dB (!) notch filter right at 20Hz.
Btw to get the bass right you absolutely need a mic, no way you can do this without.
I simply activated the HPF in the 18s which is only available for 80Hz. But works perfectly.
Also activated the LPF at 80Hz (24dB/Octave) (here lots of other frequencies available in 10Hz steps.)
Then entered the distances of all speakers to the listener position. In my case 90cm for the monitors and 140cm for the Sub. This is a very nice feature, I'm not sure but I think before adjusting this the sound was not as tight as it is now.
Attached the in room response, averaged. Within a 30cm box the response does not change up to 350Hz.

It sounds awesome, a lot of tracks get more body to it, even though the setup without sub already went down to 35Hz.
Everything lower than the 35Hz sounds so natural and effortless, I love it.
I do not think a Genelec sub could have done it better than this.

Some minor things that I noticed:
Firmware flash to new version was extremely fast. The manual stated 1-3min but is was more like 3 seconds.
The firmware on the sub did not have the HPF setting but the newest firmware (V004.0011) on the Dynaudio site has it.
There is increased tweeter hiss from the monitors by connecting them to the 18s. Before I could not hear the tweeter hiss at all but now when the room is quiet it is noticable.
I noticed that entering the distances in the Sub would give a loud pop when entering the value. Better to turn off the monitors before doing this.
nice results, I wonder how can you activate on the 18S both HPF and LPF? is that the HPF at 80hz is default to be 24db/octave and then the LPF is for the output, basically creating the same roll off slope for the 8040B?
 
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