Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Anthony William]

Hello I have a chance to pick up a PL236 for under $500 was thinking of using it with my RMX 850 to run my ev SX500+'s bi-amp mode. Any feed back would be appreciated.

[Silas Pradetto]

Great amp.

There's more to biamping speakers than just another amp. Do you have the EV required DSP? Do you have a way to port the EV DSP settings over to another platform?

And an RMX850 is probably a bit small to have enough voltage swing to really wake up those HF drivers.

[Anthony William]

Hey Silas, Thanks for your response.
I'm aware there's more to it than just another amp, although I am no expert.
I plan on processing the signal through EQs, crossovers and comp/limiter.
I,m aware the PL236 has a data port for external dsp or computer control of
internal dsp board if equipped. Thats stuff I don't know much about. Also
I am an Ableton user so was thinking of processing signal through that. I
know Depesch Modes Drummer does this. so I don't see why it wouldn't work
for me I will be using my rig for electronic music, mostly techno.  I also have two EVX 180A's that I will build cabs for and an EV MTL-1 .
So my RMX 850 is to small, do you think it would make sense to use it at all or run my tops straight off say the PL236 if I pick it up?

[John Livings]

Hi Anthony,


Your Speakers;

http://www.electrovoice.com/sitefiles/downloads/sx500-eds.pd f

Your Amp;

http://www.qscaudio.com/pdfs/Specifications/RMX_spec.pdf

The Amp you are buying;

http://www.qscaudio.com/products/amps/powerlight2/powerlight 2.htm

It looks to me that your RMX-850 (180W Per Channel @ 8 Ohm's) is more than enough for the HF drivers (60W) of the EVX 180A's.

It is not my intention to step on any toes here, As I am a student of this stuff myself.

Anyone?

Regards,  John

[Silas Pradetto]

Anthony William wrote on Wed, 16 February 2011 17:32

Hey Silas, Thanks for your response. I'm aware there's more to it than just another amp, although I am no expert. I plan on processing the signal through EQs, crossovers and comp/limiter. I,m aware the PL236 has a data port for external dsp or computer control of internal dsp board if equipped. Thats stuff I don't know much about. Also I am an Ableton user so was thinking of processing signal through that. I know Depesch Modes Drummer does this. so I don't see why it wouldn't work for me I will be using my rig for electronic music, mostly techno.  I also have two EVX 180A's that I will build cabs for and an EV MTL-1 . So my RMX 850 is to small, do you think it would make sense to use it at all or run my tops straight off say the PL236 if I pick it up?

Based on what you mentioned, I would not recommend attempting to biamp. It is far more complex than you think, and requires the manufacturer's DSP for proper results, unless you have a measurement system which would allow you to use any DSP. I highly recommend contacting EV for their explanation, as they will strongly dissuade you from what you are trying to do above.

And no, DSP cannot really be done on a computer, at least in real-time, without special hardware and a lot more trouble than it's worth.

It is now more economical to buy a cheap DSP than to attempt to use analog equipment, for too many reasons.

And don't mix subs. Make a copy of the MTL1 or get matching subs.

And John, just like any speaker, you have to look at the HF drivers as requiring voltage to operate, not watts. Look at the impedance plot of the SX500 at 3.5k. It is over 100 ohms. Now how many volts do you think that is, to get to 60 watts? That's over 77 volts. Now, if the RMX850 can do 200 watts at 8 ohms, that's only 40 volts, not even close to enough to get those HF drivers really going.

You would need an amplifier rated for approximately 750 watts at 8 ohms to get the necessary voltage to run the HF drivers to their rated power handling.

[John Livings]

Hi Silas,

Thanks for the clarification, Still getting my head around the Amp Imput/ Amp Output/Speaker Draw .

Regards,  John

[Bob Lee (QSC)]

Silas Pradetto wrote on Wed, 16 February 2011 18:31

you have to look at the HF drivers as requiring voltage to operate, not watts. Look at the impedance plot of the SX500 at 3.5k. It is over 100 ohms.

Very astute observation, Silas!

I wish more people would think in terms of voltage when considering amplifiers and loudspeakers.

[jeff harrell]

Bob Lee (QSC) wrote on Mon, 21 February 2011 10:33

Silas Pradetto wrote on Wed, 16 February 2011 18:31 you have to look at the HF drivers as requiring voltage to operate, not watts. Look at the impedance plot of the SX500 at 3.5k. It is over 100 ohms. Very astute observation, Silas! I wish more people would think in terms of voltage when considering amplifiers and loudspeakers.

i have a question for you Bob Lee. i have qsc 3800 and from the schematic it looks as if it puts out 95 volts max on the high rail(51 volts on the low rail.) to the speakers. is this correct ? looks like the QSC 3500 puts out 92volts on the high rail. is this what your refering to ? why would it be important to look at the voltage going to the speaker if the speaker cables are 10 gauge and less then 25 feet ? btw these old amps have alota of UMPH to them !

[Bob Lee (QSC)]

I'm referring to amplifiers' actual output voltages to the loudspeakers--or the input voltages to the loudspeakers.

Sorry, I'm not clear on your loudspeaker cable question.

[jeff harrell]

Bob Lee (QSC) wrote on Fri, 25 February 2011 13:57

I'm referring to amplifiers' actual output voltages to the loudspeakers--or the input voltages to the loudspeakers. Sorry, I'm not clear on your loudspeaker cable question.

i'm the guy that talked to you on the phone today. thanks for the info about output voltage vs wattage.