Hi there,
I know most PA speakers now use DSP. But if I was to include a good DSP, like MiniDSP into my speaker, it would double the cost of my amplifier/signal path.
Im going to use an IcePower amplifier coating around £100, and as far as I understand the cheapest MiniDSP module is about the same cost...?
The thing is, I only need a few notches of EQ. Can it be done with a passive EQ setup? Is this something one can buy?
Thank you!
I know most PA speakers now use DSP. But if I was to include a good DSP, like MiniDSP into my speaker, it would double the cost of my amplifier/signal path.
Im going to use an IcePower amplifier coating around £100, and as far as I understand the cheapest MiniDSP module is about the same cost...?
The thing is, I only need a few notches of EQ. Can it be done with a passive EQ setup? Is this something one can buy?
Thank you!
I assume you are talking line level. It is possible, but difficult as it requires tank circuits and you still need buffers. I bet buying the coils would cost more than going DSP. Have you considered modifying the crossover? Is this an actual PA? Fixed location so only one EQ curve will do, or one you are going to move between locations? If the latter, you need a DEQ or similar box.
'taint no free lunch. You don't always get what you pay for, but if you don't pay for it, you won't get it.
'taint no free lunch. You don't always get what you pay for, but if you don't pay for it, you won't get it.
As creative as you want. You only cut, can't boost. All passive filters work that way.
You need to tell us a lot more about your use case to get more detailed help.
You need to tell us a lot more about your use case to get more detailed help.
Thanks,
it’s a small sealed wedge /monitor incorporating an 8” mid bass and a 1”/1” compression driver.
The only thing I think that needs adjusting is the last octave (8-16Khz) and only two notches at that.
I pricked my ears up a bit when you mentioned modifying a crossover. I’m planning to use a passive crossover from Blue Aran in Southampton (UK). I understand they are excellent, and have used them before. Particularly, it seems to me the sort of board you could modify (enough space for extra tracks).
If I simply can’t afford the DSP /processing, I’ll go without. For me the most important thing is keeping the signal path and drivers as good as possible. If the output is slightly wonky because of a few spikes, so be it.
You can easily add a first order high frequency roll off at 8kHz, just by adding a series resistor
and a shunt capacitor before the amplifier input.
For example, if the amplifier input impedance is 10k, then a series 1k resistor,and a shunt 22nF capacitor,
would be -3dB at around 8kHz. This is likely to be all that you would need.
and a shunt capacitor before the amplifier input.
For example, if the amplifier input impedance is 10k, then a series 1k resistor,and a shunt 22nF capacitor,
would be -3dB at around 8kHz. This is likely to be all that you would need.
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Peter,
Even with a "flat response" speaker, generally you would want either a 1/3 octave or multi-band parametric EQ in series with your wedge monitor to attain decent gain before feedback. Without, the +3 to 6dB 4-7kHz "presence peak" built into most vocal mics will limit GBF in addition to the 8-16kHz peaks in the monitor.
Art
Even with a "flat response" speaker, generally you would want either a 1/3 octave or multi-band parametric EQ in series with your wedge monitor to attain decent gain before feedback. Without, the +3 to 6dB 4-7kHz "presence peak" built into most vocal mics will limit GBF in addition to the 8-16kHz peaks in the monitor.
Art
Hi Peter,
What else will be in your sound system driving this?
If it's something big enough to have a digital desk, then you'd be able to set a few parametric EQ's on its output channel processing.
Obviously, if it's a small enough system that that isn't available, then that's not an option.
IIRC the cheapest dedicated outboard DSP is Thomann's own one, though granted, it's not much cheaper than the MiniDSP now. Had you been shopping a year or 2 ago, I'm sure it used to be about 70-odd quid.
FWIW,
David.
What else will be in your sound system driving this?
If it's something big enough to have a digital desk, then you'd be able to set a few parametric EQ's on its output channel processing.
Obviously, if it's a small enough system that that isn't available, then that's not an option.
IIRC the cheapest dedicated outboard DSP is Thomann's own one, though granted, it's not much cheaper than the MiniDSP now. Had you been shopping a year or 2 ago, I'm sure it used to be about 70-odd quid.
FWIW,
David.
Crossovers are specific to the drivers. Generic crossovers do not work. You have to have the impedance and frequency response of both drivers, in situ, and then choose the crossover components. This is real engineering, but fortunately well within the hobbyist domain, but it does take measurement and design.
You don't want a "flat response" speaker. Yo want a speaker that in the environment provides a smooth response rolled of gently above 6K.
Yea, a Behringer DCX is $420 US, but that is how it is done. ( crossover and DSP, specifically designed for PA use)
No one ever said good sound is cheap. Darn laws of physics get in the way.
You don't want a "flat response" speaker. Yo want a speaker that in the environment provides a smooth response rolled of gently above 6K.
Yea, a Behringer DCX is $420 US, but that is how it is done. ( crossover and DSP, specifically designed for PA use)
No one ever said good sound is cheap. Darn laws of physics get in the way.
When did I say I wanted a flat response? I just don’t want big/odd peaks and nulls and undue imbalance, like the rest of us, I would have thought.
To be honest, from experience I know that a lot of these replies are technically/ theoretically relevant, but in practice not as consequential as one would have thought.
I’ve run generic passive crossovers in speakers which used to have plate amplifiers for a while now and they work absolutely fine. No phasing around the crossover point, no nothing- nothing of any practical relevance anyway. I’m using the same crossover point, but other than that they are bone stock.
Yes I have a digital mixer. But the box isn’t just for my setup.
Even at the moment, without any EQ with my Sennheiser e845, the speaker is actually more feedback resistant than another wedge I have. Again, from experience as an engineer, GBF alone is just one issue. Reducing those ‘presence boost’ frequencies, unless it’s a condenser like a Beta87A or similar, is not a necessarily a good idea and usually yields little or no improvement. This is because those frequencies are absolutely crucial for the vocalist to be able hear adequately. Reducing them does not increase intelligibility overall. It would be better to think of intelligibility before feedback.
I think I’ve gleaned the info I need, thanks to those who have elucidated that.
To be honest, from experience I know that a lot of these replies are technically/ theoretically relevant, but in practice not as consequential as one would have thought.
I’ve run generic passive crossovers in speakers which used to have plate amplifiers for a while now and they work absolutely fine. No phasing around the crossover point, no nothing- nothing of any practical relevance anyway. I’m using the same crossover point, but other than that they are bone stock.
Yes I have a digital mixer. But the box isn’t just for my setup.
Even at the moment, without any EQ with my Sennheiser e845, the speaker is actually more feedback resistant than another wedge I have. Again, from experience as an engineer, GBF alone is just one issue. Reducing those ‘presence boost’ frequencies, unless it’s a condenser like a Beta87A or similar, is not a necessarily a good idea and usually yields little or no improvement. This is because those frequencies are absolutely crucial for the vocalist to be able hear adequately. Reducing them does not increase intelligibility overall. It would be better to think of intelligibility before feedback.
I think I’ve gleaned the info I need, thanks to those who have elucidated that.
Equalization without a DSP is possible, both before the amplifier (opamp based circuit like the Rolls RPQ 160b or Behringer FBQ1502HD) or after the amplifier (LCR networks built into the crossover within the loudspeaker), but a it will not really be cheaper than a £100 DSP. Modifying the crossover of the loudspeakers can however be worth it, because then the loudspeakers sound good without having to lug a DSP with you.
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