RCF 705AS and 312 setup

[Djanddisco]

Hi Everyone,

Just a quick question and to see if anyone else has experienced similar:
I fairly recently bought the above setup (1 sub and 2 tops). Since new I have had an issue with the sub volume, I have the gain at the 8oclock marking the sub and the 12oclock mark on the tops, at these levels the volume is ok but if I turn the sub level any higher the bass is far too much and sometimes clips.
My first thought was there was a fault with the sub so I took it back and they linked it up in store but it all worked fine with the sub level at 12oclock.
I'm now thinking it could be a level issue with the mixer. On the back if the mixer is a master gain which I can adjust but if I turn that down the level on both the sub and tops is reduced therefore to get the levels right I would need the sub at 12oclock and the tops at full.

For info I connect L/R Xlrs from the mixer to the sub, then xlrs out to each top. All the xlr cables are new and I have tried using older cables in case they were the issue. Also the eq pots are all run flat an the mixer lever is nowhere near clipping.

Any help or advise is appreciated.

Lee

[SC Events]

I have the same problem.

I use a Denon DN-X900 mixer and have the switch on the back set to -10dB. I also run the mixer at 0dB and adjust the speakers to suit the room.

[funkymook]

It's not actually a clip light on the 705 - it's telling you the limiter is kicking in. RCF advise it's OK if it flashes on and off with the beat (so it's just limiting the highest peaks), but obviously it shouldn't be lit all the time. My 702's only start to sound decent when the limiter is flashing (they need a bit of welly to perk them up), and I've been told this is OK.

Never seen my 310's limit even when I'm using a 905. The 310's are set at 12 and the 905 between 9 and 12 depending on what's required, it shouldn't be much different with your 312's.

What play-out and mixer are you using, what type of music do you play, what size room/audience are you playing to and what cross-over point are you setting on the 705?

I suspect a tweaking of the signal chain before it reaches the speakers may help - I know getting that right with mine makes a massive difference.

[Dynamic Entertainment]

Also, where are you listening to this.

I run the same set-up and find that it sounds bassy as hell behind the sub, but great on the dancefloor.

[Djanddisco]

Thanks for all your replies, in answer to some of your questions;
The mixer is a Citronic SM-FX500 linked to twin CD players and a laptop.
I've listened both behind the sub and on the dance floor - I did think this at first as I was not used to using a sub before this setup. Bit after listening to it through the shops mixer there is definitely a difference.

[funkymook]

after listening to it through the shops mixer there is definitely a difference.

Just to clarify - a difference due to another mixer being used in the shop? What sort of difference?

(I've always found it best to take all your own gear in when checking these things - far easier to swap things around to identify issues).

[Djanddisco]

Just to clarify - a difference due to another mixer being used in the shop? What sort of difference?

(I've always found it best to take all your own gear in when checking these things - far easier to swap things around to identify issues).

Just a difference in levels, the sub an tops were both set to 12oclock and it sounded fine.

[funkymook]

As I said before - it's OK to see the limit light come on in time to the beat (as long as it's not lit all the time), so perhaps you're being a bit too cautious with the sub because you thought it was a clip light?

In your first post you say the bass is far too much and sometimes 'clips' when you turn it up to 12oclock - if there's too much bass and the light is only sometimes coming on then it appears to be doing what it should (giving you more than enough bass with only occasionally setting the limit light off).

[soundmaster mobile disco]

I have the same set up,you have to adjust the base accordingly to the tops.Ie the tops are rated at 400w?.The base is rated at 800w?,so always remember you will not need as much base volume,the crossovers sorts out the tops\mid freq according to the base.
I set mine up withy the xlr from my mixer going into the 705 subs then xlr outs to the 312s input.

Hope this helps

[Djanddisco]

Unfortunately the light doesn't flash to the beat it just comes on constantly and I'm talking when the gain is not even at 10oclock never mind 12.
Soundmaster that's the exact way I set mine up too.

[funkymook]

Unfortunately the light doesn't flash to the beat it just comes on constantly and I'm talking when the gain is not even at 10oclock never mind 12.
Soundmaster that's the exact way I set mine up too.

In that case it sounds like the signal from your mixer is too hot (especially if the shop tested it with their own gear and it was OK). Can you get hold of another one to test this out?

[Djanddisco]

In that case it sounds like the signal from your mixer is too hot (especially if the shop tested it with their own gear and it was OK). Can you get hold of another one to test this out?

Yea I should be able to. It's not the end of the world it all works fine just one of them annoying little things.

[funkymook]

Yea I should be able to. It's not the end of the world it all works fine just one of them annoying little things.

You need to get to the bottom of it though, you definitely shouldn't be seeing the limit light on all the time, that won't do it any good long term. Of course the other explanation is you're trying to get more out of it than it can give, perhaps it's time for a second bass bin?

[Excalibur]

You need to get to the bottom of it though, you definitely shouldn't be seeing the limit light on all the time, that won't do it any good long term. Of course the other explanation is you're trying to get more out of it than it can give, perhaps it's time for a second bass bin?

If memory serves correctly, I think two 705/312 is John's rig. Let's just say that that he has an abundance of bass. Plenty. Loads. Lots. Oodles. Some might say an excess. I'd be really surprised if one wasn't sufficient for most purposes.

Here are some old threads which may ( or may not ) help.

Martin, in the first post, Lee says that if he turns the bass past eight o'clock, as well as clipping, he gets too much bass, so I'm not sure that he's got a shortage.

http://www.forum.mobilediscodirectory.co.uk/showthread.php?36617-Setting-Up-2-x-RCF-312A-s-amp-1-x-RCF-705-Sub&highlight=SIGNAL+CHAIN

http://www.forum.mobilediscodirectory.co.uk/showthread.php?35003-Mixer-volume-settings-amp-settings&highlight=SIGNAL+CHAIN

http://www.forum.mobilediscodirectory.co.uk/showthread.php?26440-RCF705AS-faulty-signal-LED&highlight=SIGNAL+CHAIN

And here's one which may be well worth reading. One of these days, I've got to have a go at setting up in this way. Gain structure. (http://www.soundonsound.com/sos/apr98/articles/gainstructure.html)

[Excalibur]

A couple more thoughts occur. First up, I meant to remark on this, and forgot to.


In that case it sounds like the signal from your mixer is too hot (especially if the shop tested it with their own gear and it was OK). Can you get hold of another one to test this out?

I agree completely with that, and it may simply be that the shop had set their mixers output lower. ( Funnily enough, I found recently that my mixer was turned a long way down at the back, and turning that up has given me more headroom, because I'm not running the front end anywhere near as hard to get the required output. ) It's all a question of balancing the signal all the way through the chain, so that each part of the system shares the work.

Secondly, in the exchange between Scott and Darren, it appears ( to me who doesn't personally use either, so can't be regarded as the definitive authority on this ) that the two different models, ART and AS may use the lights differently. May.

If it were me, I'd not be too concerned as to where the dials are set to on each box. These aren't the Mackies where it was quite rightly forbidden to turn the dial past twelve o'clock when using a mixer signal ( rather than a microphone, which is what the extra gain was for. An awful system. Compare it to the back of a QSC K12 which is basically a complete mixer. Brilliant. ) If the dials are set to max on the tops when you lower the mixer output , then simply adjust the sub to the required level to match them. As long as the volums is adequate for the job in hand ( And I'd be confident of having ample volume for most jobs with that rig ) and red lights anywhere in the system do no more than flicker occasionally, you're home and dry. To an enormous extent, it's a suck it and see process. Good luck, let us know how you get on, and don't be afraid to ask for more advice.

[Djanddisco]

Once again thank you all for your replies!
My cousins bringing his mixer down tomorrow so going to give that a try but now my thoughts are that the issue is with the mixers main gain (on the rear) sorry not sure of its correct name. I'm sure it's probably different on each mixer but where about should this be set to or is it a case of try it and see?

I've just had a read through the previous threads pasted by Excalibur so it's good to see its no just me having this problem, I did open up the last link but after a hard days work it looks a bit intense to be reading so think ill leave that for tomorrow.

Thanks again

[Excalibur]

but now my thoughts are that the issue is with the mixers main gain (on the rear)
Seems logical to me.


I'm sure it's probably different on each mixer but where about should this be set to or is it a case of try it and see?


It's the tried and tested method of "suck it and see" I'm afraid. Try not to alter too many things at once, so you don't get mixed up.

As to the article, just google "gain structure". I'm sure there are better/easier ones, it's just the first one I found. Basically, you're trying to set the levels so that everything would go red at the same time if you pushed it that far.

[Djanddisco]

Still not getting any further with this, I have noticed a boost button on the tops though, has anyone else got the Mk3 312's and do they use the boost?
I'm not talking about the mic boost button either that's seperate.
:confused: