TOPIC:

Hi,

I'm setting up PEQ for a Subwoofer based manufacturers specification.

I need to set the values like

18 hz, + 8 db, Q=1
21 hz, +10 db, Q=0.71
30 hz, +10db, Q= 0.71



However it lifts the level beyond 20 db (scale of the plugin display) and it seems like the 2x4 HD plugin can't handle this.
Is it true or a limit only in the display?

Best regards,

That's just a display limit. You will achieve the +28db boost.......assuming your input signal doesn't have significant level in that frequency range that would violate the 2VRMS output range of the 2x4HD.
FYI, you have the option to create those shelving filters alternatively as "high-shelf" with a negative gain. And then maybe make a commensurate level change elsewhere to compensate.

Dave.

Everything @dreite says is true but are you sure you want to be applying such a huge boost like that? That seems unlikely to be a sensible plan to me...

Thanks.

I'm glad to hear that that it is only the display.

It is the recommendation of the subwoofer manufacturer to set these values.
It will try and measure before I filter the subwoofer and see how it looks like.
I agree it is a totally wild settings and does really make much sense.

Neslo1108 wrote:

Thanks.

I'm glad to hear that that it is only the display.

It is the recommendation of the subwoofer manufacturer to set these values.
It will try and measure before I filter the subwoofer and see how it looks like.
I agree it is a totally wild settings and does really make much sense.

What's the subwoofer and would you able to post a link to the manual showing the recommendation? Im asking as it looks very wrong and it's not impossible you could damage the sub...

I'm very open to being wrong though .

Those settings don't seem outlandish to me. Many subwoofer/box combinations nowadays utilize a driver with a very strong motor in a less than optimal box size. In order to achieve a flattish response to a low frequency it's not unusual to require quite a bit of equalization.

In this case, there are peak filters recommended.......which is a somewhat different approach than using shelving filters. But, either approach can work.

Dave.

dreite wrote:

Those settings don't seem outlandish to me. Many subwoofer/box combinations nowadays utilize a driver with a very strong motor in a less than optimal box size. In order to achieve a flattish response to a low frequency it's not unusual to require quite a bit of equalization.

In this case, there are peak filters recommended.......which is a somewhat different approach than using shelving filters. But, either approach can work.

Dave.

Really as much as 25-30 dB like this? I'm amazed if this is true but I have no experience of DIY subwoofers.

Hi,

28 db increase is like 25 times the normal input voltage.
Yes they would like to sell the Subwoofer unit with Poweramp with limiter as they are also affraid of overload of the subwoofer.

I can't reweil the manual as it internal documentation which is confidential.
I will get it in the weekend for testing.

It is very compact for building into walls but as you can see it comes with a price in the filter boost in the low end.
I might go for closed box with Linkwitz transform filter (trueaudio.com/st_lkxfm.htm) instead as it wil not require so much boost in the low end. Typically 15db shelf filter and then 10Hz HP filter.