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Not exactly karaoke but:


I’m looking for some info on behalf of my son who plays in a group.
They currently have a basic PA setup consisting of a (oldish but reliable) Carlsbro CDX 8+2 powered mixer and a pair of peavey Hisys 2 speakers.
He was looking to add a pair (or one if possible) of subs but we are not sure if this is possible or how to go about it.
His powered mixer is rated at 2 X 300W into 4 Ohms - the hisys 2 speakers are 4 ohms. He was looking to feed the output from the powered mixer into the Subs ( with built in crossovers?) and then feed the signal out of the bass bins into the Hisys
2 speakers for mid and high freqs. Does this seem OK? Also what impedance subs would we need as 4 & 8 Ohm seem to be available in most ranges.
The mixer also has a line out ( Left and Right on 1/4 jacks) would it be better to use these to feed a powered Sub and then leave the Hisys 2`s on the main output? But this would also send voice etc. to the subs?
Also the mixer has a FX send 1/4 jack output to send the sound to external processing units etc. could this be useful for sending to the Subs?
If required how would I hook up a external crossover to deal with just the Subs?
Sorry for so many questions but thanks for reading.

Any other ideas or suggestions welcome.

Cheers

Paul

Not having the manual to the mixer available, it could be possible to use an external crossover, run the line out of the mixer to the crossover in a 2 way mode (sub/full range) and send the full range back to a pre-amp in on the mixer to push the tops, then the sub out on the crossover to the powered sub. If the mixer does not have a pre-amp inputs then this would not work.
You could use the line out of the mixer to send to the powered sub - most powered subs have a built in low pass filter of some sort built in, downfall there is the top cabs would still be trying to reproduce to their lowest freqency which could cause some phase cancellation between them & the sub actually making it sound worse (not always, but it is common). Using the FX send for a sub is not recommended.

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LIKE Lonman on Facebook - Lonman Productions Karaoke & my main site via my profile!

The jacks Lonman is talking about are often called "POWER AMP INSERT," and would probably be located near the main line-level output connectors. I couldn't find the manual to that mixer, so I do not know if it has the appropriate jacks.

If it has "MAIN INSERT" jacks, you can also use that to do what you want; but there is a compromise ... the headphones will no longer be full-range when listening to the main mix. You can probably live with that.

This company in London (http://www.mattsnowball.com/pa.html) rents the mixer you own, but I was not able to find a manual or picture of it online.

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Jeff Wheeler, moonlight DJ/KJ

Hi

Big thanks for the replies.

The mixer does not have a pre amp input - I have a copy of the manual in PDF if anyone wants a look let me have your email addy and I will forward a copy.

What about the option to send all the main output to a pair of passive subs with built in crossovers and then feed the signal out of the subs crossover into the the tops?
Not sure what impedance Subs I would need though?
Looking at something like:
http://cgi.ebay.co.uk/Bass-Bin-Speakers ... 286.c0.m14

On a different subject - I found this site which is very useful for finding specific Karaoke tracks . It lets you search by track, Artist or disc and have used a few times to locate which Disc to look at for a certain track.
http://www.karaokebooks.com/search/inde ... =2720&dy=n

Thanks again

Paul

Does that amp have enough power to run a sub?

Those HiSys cabs already a 4 ohm speaker, you cannot add any more speakers to that amp as it is stable to a 4 ohm load so running the subs & tops would not work - you would most likely blow the amp. The two subs with the top cabs would create around a 2-3 ohm load per channel for the amp.
Best bet would be just to find a couple good powered subs with a built in low pass filter & run with the line out.
Or even better although probably not in the budget or plans, just throwing it out as possible future upgrade ideas - would be bypass the internal amp on the mixer altogether & get a couple external amps with a electronic crossover of some sort. The HiSys speakers are Black Widow equipped, they should have an amp that is capable of pushing 700-1000 watts for the best quality sound. QSC GX5 would be a great choice for the two top cabs giving them 700 watts per channel. Then for the sub amp - for the particular subs you linked to - they 'claim' to be 250 watts max at 8 ohms - however again, they are Black Widow equipped & would handle 500-750 watts with no problem. Get an amp that is bridgeable to 4 ohms that is able to push anywhere from 1000-1400 watts at 4 ohms, put both subs on the bridged connection & you will be sounding very good.
http://pro-audio.musiciansfriend.com/pr ... sku=481564
or
http://pro-audio.musiciansfriend.com/pr ... sku=480696 - not my first choice but others have had good luck with it.

Basic 2 way crossover that has a sub summing capability
http://pro-audio.musiciansfriend.com/pr ... sku=183507

Again, I know this isn't what you were exactly looking for however would be a better alternative.

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LIKE Lonman on Facebook - Lonman Productions Karaoke & my main site via my profile!

Hi Folks

Big thanks for all the info.

As Lonman said it may be time to consider upgrading probably start with a mixer - just wondering what people would recommend suitable for a small band say minimum of about 8 inputs including a stereo input for Computer/ipod/cd etc?
Built in reverb effects would also be good.


Cheers

Paul

Why do wish to add subs ? Normally only prerecorded music, sometimes keyboards, bass guitar and mic'ed drums (kick & toms) benefit from subs.

This PA is seriously under powered if you intend feeding any of the above into the mix along with the vocals.

There is no useable low frequency content in a vocal only PA setup either to warrant using subs.

What exactly do you want to put into your PA ?

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Gadget's Karaoke : Boldly singing what no one has dared sing before.

Hi

The PA is used mainly for my sons band. Its there first setup so money was very tight. However the sound with the Hisys2 speakers is suprisingly good as they have 15" speakers. They are looking to add subs which was my original question above. They are looking to maybe mic up drums and possibly DI the bass directly into the PA or at least mic it up.
I think following on from Lonman the system is underpowered and adding subs is a futile exercise. My son says he is maybe looking to start looking for replacement components although he wants to stil use the Hisys2 speakers. He is going to look for passive mixer first and is open to suggestions. He is a student with a part time job so funds are tight. Looking at something like:
http://cgi.ebay.co.uk/Soundcraft-Spirit ... 286.c0.m14

This seems to have plenty of scope for expansion.

Also looked at newer yamaha units with built in effects:
http://uk.yamaha.com/en/products/music_ ... s/mg124cx/

But these are more expensive but do contain reverb etc.

Cheers

Paul

What kind of music are they playing? If it's rock and heavier, then you will definitely benefit from adding a couple subs and more power. With the 15" tops, i'd actually opt for a couple 18" subs if it were me.
Good passive mixer
http://www.americanmusical.com/Item--i- ... 162DX-LIST

I know when I run sound I use up 8-10 channels on drums alone - you could actually use the powered board for a on stage drum mixer, . 4 for vocals, then guitars, bass & keys (if any).

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LIKE Lonman on Facebook - Lonman Productions Karaoke & my main site via my profile!

Or this baby......like mine

http://cgi.ebay.co.uk/allan-heath-mix-w ... 286.c0.m14

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Gadget's Karaoke : Boldly singing what no one has dared sing before.

Hi Folks

They play all sorts of covers, Bryan Adams, Oasis, Beatles, Neil Young, Johny cash etc.

I think the 18" subs would be good and its something to look for when funds allow.

The Allen and Heath boards are really good and the sound techs at the local venues say they are excellent and they also recomend soundcraft stuff.

I have heard as the Yamaha stuff is not too bad sounding and very reliable and cheaper on price.

I`ve got my eye on two items on Ebay which are only about 1 hour away - both items are MG16-6FX units are seem to have a good spec. Reviews on the net seem to be favourable.
Will keep you posted.

Thanks again for all help.

Paul

Hi Folks

Following on with this topic my son has just purchased a S/H Yamaha 16-6FX mixer as the specs look good and there is more flexability with the Inputs and outputs than his powered mixer.
Looking at Lonmans choice of Amp etc. seems good and a power amp will be his next project - The GX 5 looks good and will allow him to use the mixer with his Hi sys 2 speakers while he saves (more) to fund the crossover and bass amp/cab setup.
I`m looking for some info on Rack mounting stuff so that its portable with minimum setup at venues. I work for a sheet metal company and can make/source most stuff but I`m looking for standard dimensions of racks and any info on design etc.

Cheers

Paul

Just keep in mind I was trying to give a recommendation for your 'current' equipment. Those GX5 amps are certainly nice, but they are also limited & since your speakers are already 4 ohms, you wouldn't be able to add another pair of speakers to it. Just something to keep in mind. Otherwise for now they will be very good for the system outlined currently.

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LIKE Lonman on Facebook - Lonman Productions Karaoke & my main site via my profile!

Hi

Thanks for the info Lonman - what other amps would you consider for future purchases?
Don`t want to have to pay a fortune as my Son is a Student so budget is tight but ideal Amp would be a full range to drive the Hi sys 2 speakers for now then later add a crossover and amp suitable for bass bins and still retain the first amp for Hi sys 2`s
Yes speakers are 4 ohm so amp would need to be something like 2 X 500w into 4 ohm?
What other options on the amp output should we look for as you mention running two sets of speakers?

Thanks again

Paul

If you don't plan on adding more speakers in the future, then this amp will be more than adequate. When you do get subs, you will be able to keep this amp for the HiSys speakers & get another amp for the subs.

This amp pushes 700 watts per channel into 4 ohms.


What I was meaning is if you wanted to add another set of cabs like the HiSys (or equivalent). The amp is only stable to 4 ohms per channel which the HiSys are. If you added another set of speakers WITH the Hisys speaker, it would drop below. The only other alternative would be get 2 sets of 8 ohm speakers or a different amp capable of a 2 ohm load per channel. It sounds like you plan on staying with the HiSys speakers in which case, again you will be fine with this amp.

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LIKE Lonman on Facebook - Lonman Productions Karaoke & my main site via my profile!

Hi Folks

A big thanks to everyone for thier replies.

Paul