I've got a DBX 234XS crossover which I use in my home stereo using XLR to RCA cables I made and XLR to 1/4" balanced to connect to the USB audio interface.
Anyways when I turn off power to the power strip everything is plugged into, there is a nice pop in my speakers.
Is it normal for the 234XS to cause that sort of pop and if so can it be fixed, or does it have a problem?
Also, if it is normal and no fix can be done, what is a decent 2 way 24 dB/octave active crossover that does not produce any pop in the speakers?
Anyways when I turn off power to the power strip everything is plugged into, there is a nice pop in my speakers.
Is it normal for the 234XS to cause that sort of pop and if so can it be fixed, or does it have a problem?
Also, if it is normal and no fix can be done, what is a decent 2 way 24 dB/octave active crossover that does not produce any pop in the speakers?
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Pull the plug of the outlet strip instead of switching it off.
If the noise does not happen, the noise source is the outlet strip power switch.
If the DBX does produce the noise, add a muting circuit to the audio output of each noisy channel.
This is just a series resistor followed by normally closed relay contacts shunt to ground.
The relay coils should be directly powered by the AC line.
If the noise does not happen, the noise source is the outlet strip power switch.
If the DBX does produce the noise, add a muting circuit to the audio output of each noisy channel.
This is just a series resistor followed by normally closed relay contacts shunt to ground.
The relay coils should be directly powered by the AC line.
The amplifier in any system should always be the first thing turned off and the last turned on, most amplifiers have a speaker protection relay that disconnects the speakers as soon as AC power is lost or in the event of an amplifier fault, but some don't so this power up/down sequence becomes even more important.
It's the crossover. Unplugging the power cord produced the same result.
Unfortunately the Adcom GFA 545II does not have a speaker protection relay.
I would have thought either the circuit would have been made to not pop or have relays built in to disconnect the outputs upon turnoff given it was made by a good manufacturer.
Unless I find a crossover that will not have a pop on turn off, I will build a box with four DPDT relays and a supply that will allow them to turn off quick.
Unfortunately the Adcom GFA 545II does not have a speaker protection relay.
I would have thought either the circuit would have been made to not pop or have relays built in to disconnect the outputs upon turnoff given it was made by a good manufacturer.
Unless I find a crossover that will not have a pop on turn off, I will build a box with four DPDT relays and a supply that will allow them to turn off quick.
So I remembered that I had a Kicker KX2 crossover I had used for something else but it ultimately didn't work good there.
I decided to try it in place of the DBX and it doesn't cause any pop.
I may use that one until I can get a better crossover.
I decided to try it in place of the DBX and it doesn't cause any pop.
I may use that one until I can get a better crossover.
Looks like I may just build a box with the necessary relays to disconnect the outputs as that would be a whole lot cheaper than trying to find a good crossover.
At one point several years ago, I wanted to try DSP for a crossover, but decided against it as the audio quality would be limited by the ADC and DAC of the DSP.
I might connect the pro audio crossover output to a scope just to see what is happening at turn off. I'm thinking what is happening is that maybe the OP-AMPs have a slight oscillation as their supply voltage drops close to zero.
I think the reason I never noticed the issue was that all previous amps I've had used speaker protection relays.
It wouldn't be an issue, but I have speakers rated at about 20 watts running on an Adcom GFA 545II which is a 100WPC amp and I'd rather not blow the speakers.
At one point several years ago, I wanted to try DSP for a crossover, but decided against it as the audio quality would be limited by the ADC and DAC of the DSP.
I might connect the pro audio crossover output to a scope just to see what is happening at turn off. I'm thinking what is happening is that maybe the OP-AMPs have a slight oscillation as their supply voltage drops close to zero.
I think the reason I never noticed the issue was that all previous amps I've had used speaker protection relays.
It wouldn't be an issue, but I have speakers rated at about 20 watts running on an Adcom GFA 545II which is a 100WPC amp and I'd rather not blow the speakers.
The solution I've come up with is to use two 4PST relays and a supply that will de-energize quickly with it all being put in a box using 1/4" jacks for the input and RCA jacks for the output.
That way I can use standard XLR to 1/4" cables to go from the crossover to the box and standard RCA cables to go from the box to the amplifiers. I'll use 1/4" balanced jacks with the ring wired to the sleeve so as to properly unbalance the signal.
That way I can use standard XLR to 1/4" cables to go from the crossover to the box and standard RCA cables to go from the box to the amplifiers. I'll use 1/4" balanced jacks with the ring wired to the sleeve so as to properly unbalance the signal.
Also have an DBX 234XS active filter which seems to cause my Krell solid state to shut down.
Everything had worked fine for ca 2 years, but now amp shut down (protection mode) after 2-3 sec.
First one had 3-4 dB output differance on left and right channel, so i send it back and get unother one.
Here is my thread
Also like you im looking for "a better" active xover, but seems expensive.
regards John
i get the convenience of having one switch turn everything on and off but i follow conanski's suggestion power amps on last and off first....
have you looked at or thought of power sequencers?
have you looked at or thought of power sequencers?
If you mean Krell´s "power-up-sequence" everything seems normal.
It counts down from 10 and then starts up.
Very nice power sequencer.
Could wire it up to four standard outlets with the hot link disconnected between both plugs of each outlet and put it all in a box with a 10A fuse in each hot lead to the outlets so that the relays aren't overloaded.
Could wire it up to four standard outlets with the hot link disconnected between both plugs of each outlet and put it all in a box with a 10A fuse in each hot lead to the outlets so that the relays aren't overloaded.
Yes, but can´t understand why it now works perfect in my livingroom with RCA from an old Onkyo receiver.
In the musicroom in the basement connected with XLR from Yamaha preamp and trough an DBX 234XS active filter, it shut down after 2-3 sec ?
Have suspect the active xover after my tests on the kitchentable this saturday, it works perfect from RCA from my livingroom-receiver.
The amp is on my kitchentable since last week, i have really bad back and neck and shoulders, so can´t lift the 47 kilo amp to the basement.
Must wait to a friend comes by to be able to test XLR without the DBX active xover.
Only my Yamaha in the basement have XLR output.
Wonder what can be wrong in the active xover?
Using XLR all the way.
Yamaha 11.2 channel preamp to DBX 234XS active filter, and from there to 2 Krell stereoamps.
Everyting over 340 hz to MTM amp (passive 2way xover in mtm), and everything under 340 hz to woofer amp