13 replies to this topic

[freshairmini]

Saw this amp on the talkaudio forum
Phoenix Gold Xenon 100.4


Is it any good?

and

would it be too powerful for some focal 130KR speakers?

[Ruckus]

Running active? I guess based on your last few thread that's a yes.


So that will be 100watts per driver, that is high for those comps, but NOT a problem.

Keep the gains on the Tweeter channels set close to flat and the Mid to no more that a 1/4 higher.

This way you are attenuating the tweeters. Tweeter are a lot more efficient that woofers, so to keep a good balance the lower gain will deliver a little less power.

And just go easy on the volume knob till you get to 'know' the system.

[freshairmini]

So do the gains control the volume limit then?

[Ruckus]

No but yes... LOL

Gain control on a amp is the device that match's the input sensitivity to the output voltage from the source unit. i.e the RCA outputs.

Example:

An amp has an input range for 2volts to 10volts,

• If the the source unit outputs 2volts then the gains can be set to there maximum input point.
• If the the source unit outputs 10volts then the gains should be set to there minimum input point.
• If the the source unit outputs 6volts then the gains can be set to (but no higher than) the middle input point.

You can always set gains lower but you should not go higher (well not by much) as over gaining (boosting) a single will intoduce clipping... which hurts speakers and sounds awful.

So basically once the gains are setup correctly to match the output of the headunit, you can cut one back to attenuate and set of speakers or a sub.

In a fully active system I normally have the Sub amp set to the maximum gain to match the headunit/processer output, the Mids and little back and the tweeter a little more.

BUT all that said if you have loads of power on tap, winding the gains back can help reduce system noise (hiss), that why its never really an issue to have more power on tap than you need... its called Headroom

[Ruckus]

Read:

http://www.bcae1.com/gaincon2.htm

http://www.talkaudio...um-performance/

http://www.talkaudio...n-the-sq-world/

Edited by Ruckus, 08 November 2011 - 05:09 PM.

[freshairmini]

Well looks like I'm getting that amp, read a really interesting review about it, turns out its quite a find!

If anyones interested read it here

[Ruckus]

They are great amps...

[freshairmini]

No but yes... LOL

Gain control on a amp is the device that match's the input sensitivity to the output voltage from the source unit. i.e the RCA outputs.

Example:

An amp has an input range for 2volts to 10volts,

• If the the source unit outputs 2volts then the gains can be set to there maximum input point.
• If the the source unit outputs 10volts then the gains should be set to there minimum input point.
• If the the source unit outputs 6volts then the gains can be set to (but no higher than) the middle input point.

You can always set gains lower but you should not go higher (well not by much) as over gaining (boosting) a single will intoduce clipping... which hurts speakers and sounds awful.

So basically once the gains are setup correctly to match the output of the headunit, you can cut one back to attenuate and set of speakers or a sub.

In a fully active system I normally have the Sub amp set to the maximum gain to match the headunit/processer output, the Mids and little back and the tweeter a little more.

BUT all that said if you have loads of power on tap, winding the gains back can help reduce system noise (hiss), that why its never really an issue to have more power on tap than you need... its called Headroom

oh i see, so ideally to make sure you get the gains correctly you would find out the maximum output volts of your head unit and match that with the gain adjuster on the amp with a multimeter maybe?

[Ruckus]

Yes

Or if you're lucky, once you know the max output of the headunit (in the manual), there will be markings on the adjuster itself.

[freshairmini]

Ok just been looking at that first link with the gain calculator, and just been having a fiddle

From what Im understanding, what you set the gain at will affect what amount of watts will be going to the speakers at a given volume depending what the voltage is on the rca outputs on the head unit is.

So am i right in saying that if my head unit has a pre output voltage of 2v (it does) before clipping i would ideally want to set the amp slightly above that voltage, say 2.5v then that would mean the watts going to the lower powered speakers would be within there safe rms power range, if I wanted to stay within that.

Edited by freshairmini, 08 November 2011 - 06:02 PM.

[Ruckus]

Bingo, and set the tweeters (if your running active) a little less than the mids.

[freshairmini]

Brillo! thanks ruckus, I can now finally say I can install all this and not end up melting my speakers lol.

That first link with the gains calculator was really useful in figuring it all out, i'll have to remember that one!

[Ruckus]

Lol I really hate the lack of edit on this forum
Now..

"If the the" what!?? LoL

[freshairmini]

oh yeah lol, just saw that, I was thinkin whats he on about last night