High Pass Filter and other observations

Hello,
Last night I was working at a show and had some time to look at the very cool new spectrum analysis tools in VSL-1.6, which I like a lot! I used it to look at the effectiveness of the high pass filter and I have to say I don't think its very good. We had an auctioneer using a hand held radio, that was looking after itself, and in order to make a noticeable reduction in frequencies below 100Hz the filter had to be set to at least 240Hz. By contrast if I used the FAT Channel EQ with the low band set to shelf and the width to very tight I could make a visible difference in the reduction of 100Hz by centering the frequency sweep at 100Hz.

So this leads me to my point that I think the 6dB/Oct setting of the HPF is too low, it should be at least 12dB/Oct or perhaps even higher. It seems crazy that I need to use up one of the 4 bands of the FAT channel EQ as an effective HPF when there is one available.

On another note it would be great if the effects of HPF could shown on the EQ section of the FAT Channel on VSL It makes sense to me that it should.

Andrew

This is a long standing issue. Appreciate the extra vote on it.

We've passed it to Presonus and it's on their list for certain, but where it sits on that list I couldn't tell you.

Ditto. I also want a low pass filter.

This message was edited 1 time. Last update was at 10/07/2012 13:09:43

lowdbrent wrote:Ditto. I also want a low pass filter.

Glad someone other than me can see how useful a feature that would be. I had the same suggestion poo-pooed in this thread...

http://forums.presonus.com/posts/list/22540.page

Also, is it possible to delay auxilliary channels? Would be usefull at one venue where I'd like to setup a pair of speakers halfway up the room.

for steeper HPFs. 18dB/oct would seem about right

Of course there will be some grumbling: All saved scenes and channel settings will need tweaking when the HPFs are changed. So it would be a good idea to make sure that any other 'scene changing' improvements are implemented at the same time.

My suggestion would be to take the opportunity to make 16.4.2 saved settings compatible with the 24.4.2. The other way won't work of course, but storing the fixed 16.4.2 PEQ Qs (.55 and 2) in the htmls would open the door to maybe have menu selectable Qs in the future. Wishful thinking?

This message was edited 1 time. Last update was at 10/07/2012 14:13:28

Also, is it possible to delay auxilliary channels? Would be usefull at one venue where I'd like to setup a pair of speakers halfway up the room

You would normaly use a sub bus for satelite speakers, the four subs each have a built in delay for just this purpose

I like to use subs to tie mix elements together. Compressing grouped drums, backing vox etc.

It's been fairly common in the larger venues and festivals I've done to have delays and infills on post fader auxilliary channels or matrix outs.

SwitchBack wrote: for steeper HPFs. 18dB/oct would seem about right

Yeah I would go for 18dB/Oct.
For the type of work we do with our SL I don't see a pressing need for a LPF but can see how it would be useful in other situations.
Displaying the filters effects on VSL and SL remote has to be a winner too.

Andrew

Why not 18dB/octave high pass AND low pass? The higher frequencies can get just as crowded as the lower ones...

Hm, I'd say the 4-band PEQ is adequate for channel LPF if needed. The only use I see for a steep LPF is in combination with aux fed subwoofers. So maybe on the auxes?

But since this starts to become sort of a wish list i'd like to add another one:
Currently the auxes don't have a MUTE button. I'd love to see a menu option where the pre/post settings moves to the system menu and the POST buttons become MUTE buttons. In a live situation I don't flip pre/post as much (= never) as I would like to have a quick way to (temporarily) mute the auxes. The red POST buttons would do perfectly.

SwitchBack wrote:Hm, I'd say the 4-band PEQ is adequate for channel LPF if needed. The only use I see for a steep LPF is in combination with aux fed subwoofers. So maybe on the auxes?

I reckon thats reason enough! Useful to be able to feed the sub of a drum-fill with it's own dedicated low passed aux. Handy for giving a drummer more sub to the kick or bass in their fill when doing so on the channels would sacrifice the FOH mix.

As I've mentioned elsewhere, with other desks, I've been known to low pass and heavily compress an effects return fed bassy instruments from an aux to have extra low end on a fader.

Back to the original point of this thread however, the high pass should definitely be steeper.

Switch - I'm all for a Aux mute too ....

Been calling for a useable HPF for YEARS
also
1. Aux mutes
2. Screen/function ( Overview, Aux mixer , Graphic EQ, Settings), select on Ipad moved to the top. Too easy to switch functions with palm/pinky
3. variable scroll, not HARD left or HARD right when you want top move from channel 12 to say 13/14 where my vocals are .. it would be nice to be able to view whatever group of faders you want.... not 1-12 or 5-16... center on my workflow area... instruments and vox...
4. Remote offline setup capability (currently under development by a USER group, thanks Jon!)
5. Less fritzy update/download procedures. A failsafe go/nogo download verifier would be nice... too many incomplete/bad downloads

I'll quit while I'm behind...

gadget69 wrote:Been calling for a useable HPF for YEARS
also
1. Aux mutes
2. Screen/function ( Overview, Aux mixer , Graphic EQ, Settings), select on Ipad moved to the top. Too easy to switch functions with palm/pinky
3. variable scroll, not HARD left or HARD right when you want top move from channel 12 to say 13/14 where my vocals are .. it would be nice to be able to view whatever group of faders you want.... not 1-12 or 5-16... center on my workflow area... instruments and vox...
4. Remote offline setup capability (currently under development by a USER group, thanks Jon!)
5. Less fritzy update/download procedures. A failsafe go/nogo download verifier would be nice... too many incomplete/bad downloads

I'll quit while I'm behind...

Agree with 1, 2, 4, and 5. 3 is on your "settings" page at the bottom of SLR Overview. Turn "Scroll By Page" off.

I agree - an 18db would b a better lpf for sure.