PA Speakers

[jacqui01]

I want to replace my Speakers the main reason is the ones I have are in Wooden Cabinets and are just too heavy,
(Studiomaster KMX- 12" 350 watt each, I've had them about 10 years, and I am sure there is more advanced & lighter around now.
I was recently recommended RCF Speakers, and wondered if any one has experience of them, I would be looking at Passive speakers, as I want to use my existing amp with them, and keep the weight down. also I don't want to start carrying extra equipment, so I am looking at just two speakers not extra bass Bins etc.
Look forward to any ideas, Jacqui

[JohnG]

Hi Jacqui,

From the forums I have read the RCF stuff seems to be one of the best. Certainly all the guys in the Sound on Sound live forum give them top marks. I have no direct experience though.

All the best
JohnG.

[jacqui01]

Thanks John
I had a look at the site but can't find any mention of RCF's, if you find it again maybe you could give me a link to it.
Cheers
Jacqui

[levi2]

theres a few speakers now with cabinets made out of moulded plastic ie JBL EVs etc etc i would go into a music shop and test the weight of them
levi2

[weegeo]

Hiya Jacqui,
We bought a pair of RCF art322i 12` speaker 400watts each at a very good price 650.00 each but they are less than that on the mainland. They are certainly very clear and very punchy at the top end which is the sound i like it gives me a little to play around with we use them with a soundcraft 15 channel mixer and a lexicon echo and we are very pleased with the results. Hope this helps


weegeo

[JohnG]

Hi Jacqui,

Here's a link to lots of threads on SOS. Several of the people here are professionals and run big shows for well known names so their experience is worth listening to. Here's the link:

www.soundonsound.com/forum/dosearch.php?Cat=&Forum=f14&daterange=0&where=bodysub&fromsearch=1&Words=RCF&textsearch=Search+Forum

It was as a result of a search using "RCF".
HIH,
JohnG.

[ovation99]

These are made in Italy and are similar to the Mackie range.
I've used some of the powered range before and have apair of very old Monitor 5's installed in the office.
This is the UK link for all the info you need www. rcfaudio.co.uk and the address details are:

RCF UK Sales & Support Office
PO Box 2063
Leigh on Sea
Essex
SS9 5WB
Tel: (UK Customers) 0844 745 1234
Tel: (International) [phone]
Fax: [phone]


Hope this info is of use in helping your decision.

[jacqui01]

Thanks for all the information everyone
Can anyone advise on a couple of things for me, I was looking at getting the 12 inch speakers, and I have a friend interested in getting the 15 inch ones, of the same model, he does the same venues as me, but wants 15 inch ones because he has been told they will have more Bass response for the music, but when I went to a music shop near me, the sales man said that for Singers 15inch speakers are not recommended for vocals, and that most singers opt for the 12"speakers for that reason, that you can lose the top end for vocals on the larger speakers, does anyone know anything about that.
The other thing is that the Spec fro the 12" & the 15" speakers is the same, and according to the brochure I have the same weight too?
below is a link to the Spec on both speakers
www.rcfaudio.com/vediMacro.phtml/sLang/EN/IDMacro/2591/menuAttivo/1674/m1/0/ARTSeriesART312/product.htm

www.rcfaudio.com/vediMacro.phtml/sLang/EN/IDMacro/1681/menuAttivo/1674/m1/0/ARTSeriesART315/product.htm

one other thing is does the ohm have to be specific for the amp, does 4 or 8ohm make any difference, the speakers I have now are 4ohm, and I noticed a lot of the new ones I am looking at are 8ohm.
Jacqui

[shanless]

I use Wharfedale Titan 12's....great sound...clear as a bell and very light to carry...I had thought of upgrading to the 15'' versions but they were far too heavy to carry...I am content with the 12''.....I run them through a Beringer mixing desk and EP 2500watt Beringer power amp...and with a Shure SM58.....I'm happy....I think they are worth a look.

shop.etsnet.co.uk/wharfedale-titan-12-speaker-367-p.asp

[ovation99]

Hi Jacqui,
With regard to the ohms of speakers/amps (known as impedence), you must NEVER use a speaker(s) of a lower impedence rating than the amp.
However, using speakers of a higher rating will not cause any harm, it will just reduce the power of the amp output.
In all cases it is advisable to have a matching amp/speaker combination.
Hope this helps

[levi2]

we use peavy hisys speakers these comprise of a 15" blackwidow speaker a compression driver and a horn ive been told the compression driver acts like a12" speaker even though its very smalll we get a great sound for vocals and backing thru them using a soundcraft powered mixer desk We also use a powered 15" sub but only for the backing and not vocals Only downside is the peavys are heavy but with 2 blokes to lift em it not much of a problem

[JohnG]

The general rule is true that for singers, especially the female vocal range, 12 inch is kinder than 15. The larger ones will give more bass punch though, true. The crossover frequency from low to high is usually lower with 15s. Because this is right in the vocal range it is important to get right. This can also affect the smoothness of the sound of the singers voice. If you were using them only for vocals I might even say go listen to the 10s. You do not need a good low frequency response for female vocals. Smoothness and accuracy are the overriding factors IMO. 10s tend to be more linear than 12s which are more than 15s.
Just my 2d though! I bow to the more experienced here.
JohnG.

[weegeo]

We used 15`mackies for the past few years but they weigh a ton though the sound quality more than makes up for it. We changed to the 12`RCF`s and to be honest there is a little loss on the bass side, but only someone that is used to performing would notice. I would go for the 12`RCF`s Jacqui i love them

weegeo

[jacqui01]

I am a bit confused about this ohm thing, I looked on the spec for my amp a Dynacord Powermate 600
Specifications Maximum Midband Output Power, 1 kHz, THD=1%, Dual Channel: - into 4 Ohms 2 x 270 W into 8 Ohms 2 x 180 W Rated Output Power, THD=0.1%, Single Channel: - into 4 Ohms 2 x 300 W into 8 Ohms 2 x 150 W Maximum Midband Output Power, 1 kHz, THD=1%, Single Channel: - into 4 Ohms 2 x 340 W into 8 Ohms 2 x 200 W
So does this mean than using my amp with 8 ohm speakers will only give me half the output of the speakers reducing them to 150 watts each.
My partner who I gig with uses his amp when we go out, which I think is 4 ohm too, but a 1000 watt studiomater, so will the same apply here then, half the output, that seems crazy.
Jac

[thingyy]

Feb 10, 2009 12:24:10 GMT jacqui01 said:

I am a bit confused about this ohm thing, I looked on the spec for my amp a Dynacord Powermate 600
Specifications Maximum Midband Output Power, 1 kHz, THD=1%, Dual Channel: - into 4 Ohms 2 x 270 W into 8 Ohms 2 x 180 W Rated Output Power, THD=0.1%, Single Channel: - into 4 Ohms 2 x 300 W into 8 Ohms 2 x 150 W Maximum Midband Output Power, 1 kHz, THD=1%, Single Channel: - into 4 Ohms 2 x 340 W into 8 Ohms 2 x 200 W
So does this mean than using my amp with 8 ohm speakers will only give me half the output of the speakers reducing them to 150 watts each.
My partner who I gig with uses his amp when we go out, which I think is 4 ohm too, but a 1000 watt studiomater, so will the same apply here then, half the output, that seems crazy.
Jac

Yes it does but you must be sure that speaker rating is more than the output.eg 500 watt from the amp my preference would be that the speakers can handle at least 600 watts.

[ovation99]

Hi Jacqui,
Yes, generally if you double the impedence (ohms) as good as halve the wattage output. But that does not necessarily mean it's half as loud, as it's all to do with decibels(db) and sound pressure levels (spl).
The same rule applies and that is NEVER run speakers at a lower impedence than the amp is rated, in order to get more power, because all you'll do get more repair bills.

[JohnG]

Hi Jackie,

This is a mine field when you try to get info. What you need to try to find out is the efficiency rating of your current speaker. It will look something like this 89dB SPL 1W @ 1M. Which means fairly loud (89dB Sound Pressure Level) using 1 watt of power measured 1 metre away in front of the cabinet. If another speaker says 92 dB 1w/1m it is twice as efficient (3dB difference higher means noticeably louder but double the input power). So you need to look at efficiency ratings.

Next you need to look at maximum SPL. If it says 127dB SPL that means loud enough to blow your socks off, assuming you are wearing any. It will tell you (usually) how much amplifier power it needs for that, maybe 300w. (so 127dB SPL at 300w)

If we look at the ART312 spec. it says sensitivity 99dB 1W/1M. Max SPL 127dB. Ouch!
For each increase of 3dB SPL you will need double the amp power so:
99dB = 1W
102dB = 2W
105dB = 4W
108dB = 8W
111dB = 16W
114dB = 32W
117dB = 64W
120dB = 128W
123dB = 256W

So your 150W into 8ohm amp will be able to drive the RCF ART312 to about 121dB SPL. That's pretty loud, but loud enough? If you try to drive the speakers beyond 121dB the amp will try and maybe fail.

However if I take a look at a typical 4 ohm speaker from the current Studiomaster range I get this 96dB 1W/1M sensitivity. Couldn't see the maximim SPL but probably the same, so
96dB = 1W
99dB = 2W
102dB = 4W
105dB = 8W
108dB = 16W
111dB = 32W
114dB = 64W
117dB = 128W
120dB = 256W
123dB = 512W

So you need twice as much power to drive the Studiomasters as you do the RCFs to the same loudness level. Again if you try to exceed 121dB your amp will probably fail. If you want to drive either of them louder you need a bigger power amp, twice as powerful at minimum. So do you need to worry about power? That 3dB difference in sensitivity makes all the difference. This is often, but not always, the case betweeen 4s and 8s. I would say then that the RCFs will sound just as loud but better than the others. But that is just raw number crunching.

I remember doing a production in a hall at the NEC, and seeing a big double stack of maybe 20 1,000W per channel into 8 ohms Yamaha amps. They certainly heated the room we were in nicely! They also filled the auditorium well! Double ouch.

HTH?
JohnG.

[jacqui01]

Thanks again guys for all the advise, and to John for the minefield of tech info, a bit mind boggling but I think I get it, I was concerned that by getting 8 ohm instead of my current 4 ohm was going to have less volume, but if I understand you rightly this does not always follow.
Jacqui

[JohnG]

Quite right Jacqui,
In fact from the figures it looks as if you should get about the same loudness but a better sound. However often a better, less distorted sound makes you think it is playing quieter! That is it doesn't hurt as much when you turn it up! D@mn! So the temptation is to turn up the volume more. You may need to watch that. You need to go FOH to see what the sound is like to the punters, sorry audience! And remember I am just using the figures. No substitute for listening.
HTH?
JohnG.

[jacqui01]

Thanks John
Well listen is what I wanted to do, but unfortunately I can't find anywhere around that seem to stock them, a supplier with a good price near me said they may be able to get the 12" Actives in for me to hear, but then added they will have quite a different sound to the same speaker in the Passive version, I get the impression that most people just order on line these days, and bypass the shops, shame really, that never used to be the way.
So am going to phone a few more just in case anyone has some, if not might just have to take a chance, but I've not really found a bad review yet.
Jacqui