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High pass filter

Posted: Wed Dec 02, 2015 1:30 am
by franklinstower
I bought a sub 37 and a 15 inch Electro Voice PA speaker a while back. I blew the speaker playing bass not knowing that I needed to be running an eq between the Moog and the PA. The speaker is covered by warranty so I am getting a new one but I now want to protect it from working to hard playing really low frequencies. I am exploring options for doing this and among other suggestions made a high pass filter has been suggested. We play only live music and never even record it so the setup just has to be suitable for live performances. Also I have been using the sub 37 for over a year now as my bass instrument and am very happy with the sound I've gotten-- I am hoping for something that does not color the sound in any way other than to prevent certain frequencies from coming through that can harm my speaker.

I would appreciate low end and high end approaches and suggestions for this-- I have been looking at the 500 series high pass filter but it is very expensive for what I am doing....

Re: High pass filter

Posted: Wed Dec 02, 2015 2:16 am
by torinkrell
Interestingly I was just suggesting a highpass filter last weekend to protect a club's subwoofers by filtering out audio under 30 hz. With your full range EV PA speakers the highpass filter may need to be set a little higher especially if you play loudly. Ported speaker systems are more efficient in the low end at their resonant frequency and can therefore supply more bass from a reasonably small and light box. However below resonance the woofer is essentially unloaded. This means that the woofer is subject to extreme movement in response to really low frequencies that can cause damage because there is no or little damping available from the air in the cabinet below the resonance frequency. PA speakers have more rugged speaker drivers and less compliant surrounds to minimize their vulnerability to damage however a highpass filter would offer you more protection. A tube amp may also offer some protection as it is more apt to roll off at real low frequencies while some transistor amps (DC coupled) reproduce audio all the way down to or near DC. An active PA speaker with internal amplification will also often be more able to protect itself - especially if it has some active digital crossover software.

Re: High pass filter

Posted: Wed Dec 02, 2015 8:52 am
by paramnesia
You need a Loudspeaker mgmt processor, something like this
http://dbxpro.com/en-US/products/driverack-pa

Re: High pass filter

Posted: Wed Dec 02, 2015 6:44 pm
by DUBMCT
Get a powered sub, you don't want to miss any of the low end. QHC and Yorkville make some good stuff all with built in cross overs and limiters.
As others have mentioned cutting below 25 can help, dbx makes stuff and there are lots of rackmount eq's.
You don't want to miss a) the raw feeling of low end, b) seeing the wave in the smoke machine and c) rattling glasses off of the bar.

Re: High pass filter

Posted: Wed Dec 02, 2015 7:09 pm
by franklinstower
^^^^^^^

I totally agree for the big picture. A sub woofer is absolutely in the cards for me its just that it is my wife's turn for buyings stuff and there is a minor home remodel and wood floors that have to be done first.

I have gotten so much conflicting advice on what I need, or if I need anything at all, from forums, and the employees at Guitar Center that I decided to contact Electrovoice directly. They told me I shouldn't be needing anything to limit low frequencies and presumably I did not blow my speaker due to playing them through it!!! I am back to knowing nothing at all-- again.

Re: High pass filter

Posted: Thu Dec 03, 2015 3:02 am
by torinkrell
Perhaps we could give you more advice here if you provide more information about the EV Speaker and your situation - such as the EV model #, what type of amplification powers it, whether you play very loudly to be heard above several guitars and drums during your live sets, if the bass notes that you play are lower than what a standard bass guitar can reach (about 40hz), if you use any effects, & if you use the sub oscillator on your Sub 37.

Re: High pass filter

Posted: Sat Dec 05, 2015 7:16 pm
by franklinstower
torinkrell wrote:Perhaps we could give you more advice here if you provide more information about the EV Speaker and your situation - such as the EV model #, what type of amplification powers it, whether you play very loudly to be heard above several guitars and drums during your live sets, if the bass notes that you play are lower than what a standard bass guitar can reach (about 40hz), if you use any effects, & if you use the sub oscillator on your Sub 37.


Here are the specs on it. When I said I still did not know anything it was not a subtle jag at this or any online forum-- more of a having fun at the expense of myself joke since I know very little at this point. Here is the very strange thing though. My Electro Voice speaker is blown and the company is sending me a replacement. I spoke directly to a tech at Electro Voice and he said I do not need to put anything between the speaker and the synth. He was certain about that. However....

I was playing last night on a Behringer PA, just a crappy 230 dollar thing but that is relatively new. It started smelling badly and then I heard a loud popping sound and it quit working altogether while playing at not even half of its capacity!!! So I don't know if that is a coincidence or not...... I have a new EV on the way and don't know if I dare to use it. I really would appreciate help from anyone who knows what is going on. It could be a coincidence but I am beginning to wonder if my Moog is more powerful than all speakers. :D

ELX115P Active 15" Loudspeaker

Freq. Response (-3dB): 56Hz-18kHz
Freq. Range (-10dB): 44Hz-20kHz
Max. Measured SPL: 134dB
Coverage (Horiz. x Vert.): 90 x 50
Power handling: 1000W
LF Transducer: (1) EVS-15K, 381mm (15") Woofer
HF Transducer: DH-1K, 39mm (1.5") Titanium Diaphragm Compression Driver
Crossover Frequency: 1.7kHz
Connectors: (2) XLR/TRS Combo Jacks, (1) Stereo RCA, (1) XLR Link Output

Electro-Voice-engineered woofer and 1.5" titanium compression driver provide exceptional audio quality
Outstanding crossover performance
1,000W Class-D high-efficiency amplifier runs cool without fans
Biamplified design with 24dB/octave filter slopes and transducer protection
Selectable 100Hz high-pass filter for use with an external subwoofer

Re: High pass filter

Posted: Sat Dec 05, 2015 7:51 pm
by psynthetic
I would recommend something like the Klark Teknik DN360 GEQ which has a switchable HPF that will remove things below 30Hz. A limiter would probably be a good move also...
Or something like a DBX Driverack would do both and give you some more options.

EV is correct, you don't NEED to put anything between the speaker and the synth, but you do need to pay attention.
It probably has warning lights/clip indicators on the back.. plus if you were pushing it so hard you killed it then it really should've sounded like it was being abused leading up to when it died.

Also, for what it's worth, I tend to steer clear of 15" speakers, they tend not to sound very nice, i'd always take a 12" plus a sub.

I seriously doubt that it's coincidence that the Behringer died on you either.

Re: High pass filter

Posted: Sun Dec 06, 2015 9:30 pm
by franklinstower
I am really hoping to not spend that kind of money. I am hoping that a graphic equalizer guitar pedal will fill my needs.

Re: High pass filter

Posted: Mon Dec 07, 2015 2:39 pm
by Vsyevolod
franklinstower wrote:I was playing last night on a Behringer PA, just a crappy 230 dollar thing but that is relatively new. It started smelling badly and then I heard a loud popping sound and it quit working altogether while playing at not even half of its capacity!!! So I don't know if that is a coincidence or not...
This is what happens to all Behringer's at that price point...

Stephen




.

Re: High pass filter

Posted: Mon Dec 07, 2015 2:41 pm
by Vsyevolod
franklinstower wrote:I am really hoping to not spend that kind of money. I am hoping that a graphic equalizer guitar pedal will fill my needs.
It won't.

You either spend the money and protect your gear or you cheap out and are always looking over your shoulder.

Stephen




.

Re: High pass filter

Posted: Mon Dec 07, 2015 7:52 pm
by torinkrell
Ok lets try a different angle on this problem. I am going to assume that you were playing your Moog 37 very very loudly through a powered PA speaker each time you burned one out. These portable PA speakers can only handle so much really loud low bass before they blow. I believe you need to distribute the strain of stadium level volume over two or more PA speakers. This will reduce the chance of overheating and/or mechanically destroying the PA speakers and will give you more bass because the multiple woofers will compress the low end less. Perhaps you can also position one of the speakers right next to you, as a monitor, so you can hear yourself better and possibly reduce the need for so much volume to begin with.

When I play my 1973 Minimoog I use 3 PA speakers (two have 12" woofers and one has a 15" woofer) because it gives me more headroom, less distortion/compression, more bass, better monitoring, and far more uniform sound coverage throughout my studio space. I hope this helps you!

Re: High pass filter

Posted: Tue Dec 08, 2015 2:05 am
by franklinstower
torinkrell wrote:Ok lets try a different angle on this problem. I am going to assume that you were playing your Moog 37 very very loudly through a powered PA speaker each time you burned one out. These portable PA speakers can only handle so much really loud low bass before they blow. I believe you need to distribute the strain of stadium level volume over two or more PA speakers. This will reduce the chance of overheating and/or mechanically destroying the PA speakers and will give you more bass because the multiple woofers will compress the low end less. Perhaps you can also position one of the speakers right next to you, as a monitor, so you can hear yourself better and possibly reduce the need for so much volume to begin with.

When I play my 1973 Minimoog I use 3 PA speakers (two have 12" woofers and one has a 15" woofer) because it gives me more headroom, less distortion/compression, more bass, better monitoring, and far more uniform sound coverage throughout my studio space. I hope this helps you!

So far this is the most helpfull information I have been given. I kind of think this is what I need to do the only exception is that I don't think I was playing very very loudly, but I was playing kind of loud. I bet I was playing at half of the speakers total volume is all, but it was very low bass and I think that is what happened. I had planned to get another speaker eventually anyway because its my band and the music I envision is saturated in bass (but not overly loud bass) as a sort of background or building block sonically, so it makes sense that another speaker would be the way to go.

In this case since I already have a 15 would you suggest another 15 or a 12, and why don't you use a sub woofer?

Re: High pass filter

Posted: Tue Dec 08, 2015 9:28 am
by torinkrell
Second question first. I don't use a sub for my PA because I am using a high end sub with my quality studio monitors. My studio monitor system gives me full 20 - 20,000 response, while my PA speakers are more rugged and more appropriate for jamming with friends and synthesis experimentation. PA subs under $900 are more optimized for high volume than extension down to 20hz. In your situation I would suggest an identical matching EV speaker or the matching EV sub if your interest is in maximum bass reproduction in a live situation. Perhaps you could eventually get both giving you more versatility in a variety of different live settings.

Re: High pass filter

Posted: Tue Dec 08, 2015 10:28 am
by paramnesia