Wiring up

[Rolandpromotions]

Hi

 

I have just purchased 2x Cerwin Vega CV-1800 amplifiers, 2 x Skytec top speakers (model 170.159, power 300w rms) and 2x Intimidation Intimidator 375w bass bins. I am running two turntables through to a Numark PPD01 mixer, which in turn is to be wired into the amplifiers.

 

I am struggling to get them all to work perfectly. I am using a 1/4" jack to jack lead from the mixer to Amp A, then running the two skytec speakers from amp A using speakon connections. Using the other terminal on the back of the skytec speaker, I am using a lead with a speakon connection (plugged into the speaker), and feeding as an input into Amp B using a 1/4" jack. From Amp B, I am then using a speakon connection from the Amp, feeding into the bassbin on a 1/4" jack.

 

Am sure this isnt quite right, and have been reading about XLR leads. Would it be best to wire the mixer to amp A, and feed the tops from this, then using XLR leads to connect the amps together, using Amp B to feed the bins.

 

Sorry to ask, but havin just started out on my own, am in need of advice.

 

Many thanks in advance

 

 

Moderation: Moved to The Next Generation which, in the Blue Room, is the forum dedicated to beginner-level questions.

[ChazHS]

You would be better daisy-chaining out of the Amp A into Amp B, however, to do this properly you require a passive crossover between your mixer and the amplifiers.

[Doug Siddons]

Hi

 

 

Using the other terminal on the back of the skytec speaker, I am using a lead with a speakon connection (plugged into the speaker), and feeding as an input into Amp B using a 1/4" jack. From Amp B, I am then using a speakon connection from the Amp, feeding into the bassbin on a 1/4" jack.

 

 

This bit is going to get you into some very expensive repairs! Simply put the signal feeding the speaker is at speaker level and the input on the amp is looking for a line level signal . Feeding speaker level into line level will cause it and the amplifer to expire.

 

The easiest way for you to get it started is to connect the two amps together by using the XLR inputs and link effectively daisy chaining the two amps together. Signal from the desk into the input of amp "a" then an XLR lead from the link into the input of amp "b". This will not produce the best sound as ideally you need a crossover between the mixer and the amp to split the bass and high frequencies.

 

Do ensure that the leads you use for the speakers are proper speaker leads.

[wmcalin]

Hi,

 

As you have 2 power amps can I suggest you purchase an electronic xover.

Set the xover point around 150Hz for 15inch bass bins, but this can vary depends on cab design driver, etc 150Hz to the subs is a good starting point.

 

take L & R from your amp into the inputs of your xover.

 

hi out L&R from your xover to the amp driving your mid/hi speakers.

 

low out L&R from your xover to the amp driving your subs.

 

Always try to use balanced signal cable XLR or stereo jack, if your miver and amps support this ?

 

also ensure you set the xover up so you cannot clip the amps when you are running flat out.

 

Hope this helps.

[KevinE]

lead with a speakon connection (plugged into the speaker), and feeding as an input into Amp B

 

Yes, Doug beat me to it and I agree, this is the best way to blow up your amplifiers.

 

Never connect ANY speaker lead to the input of another amp unless you have a DI box rated for the full wattage of the amplifier. Outputs of amps go to inputs of speakers and outputs of mixers go to inputs of amps. If you need to run two amps then split the output of the mixer using a y-cable or adapter then feed that into the two amps. The Cerwin amps have two different input connectors, ie XLR and TRS (1/4 jack) which will be internally linked so you can use them as loop-in/out if you'd rather.

 

Most Audio Intimidation bass bins contain a passive crossover in the cabinet so you shoudn't need an external one.

[lostinvegas]

take L & R from your amp into the inputs of your xover

 

I think this should say take L & R from your mixer into the inputs of your xover.

 

If you run without a xover and the bins do not have a built in passive HPF you will blow them up.

 

Chris

[Rolandpromotions]

Brilliant, thanks to you all for your help, is sounding a hell of a lot better. You are all superstars, thanks again

[KevinE]

If you run without a xover and the bins do not have a built in passive HPF you will blow them up.

 

I dont think this will happen.

[lostinvegas]

It damages the speakers over time. The high frequencies cause the cone to travel less and more frequently resulting in the coils getting hotter quicker, which can cause warping. Over time this can cause irreparable damage. This does depend on the quality of the speakers but generally with cheaper speakers its easy to damage them. To be on the safe side you should always use a HPF or xover.

 

 

Chris

[Kevin Ross]

To be on the safe side you should always use a HPF or xover.

Shouldn’t that be LPF or high cut filter? I think you are getting a high pass filter confused with a high cut filter. However I tend to high PASS my subs at around 35hz anyway.

 

 

 

Anyway I can’t see how this would cause the kind of damage you are referring to. Yes it is not recommended and you won’t find me running any of my systems that way but the natural roll off of the cab will come into effect to tame the response of the system to usually a semi useable situation.

 

 

 

YMMV