I know the SRX pretty well.

Audiowaves has a 3 channel running 3 sets of Comps....Access, Polyglass and the new K2's...they are on switches obviously....the sub channel is running 2 12" Focal Access or a 12" Poly glass.

The SRx is probably the best value around...you can get a 3 channel for less than the price of a Kicker or Alpine. The difference in sound between the Audison and Kicker/Alpine is audible....the Audison creates a much wider stage, and MUCH more detailed IMO anyway. I had only heard the LRx untill a few weeks ago when I heard the SRx and again, the difference is audible, so I can't wait to hear the VRx

 

Do you really need the MAC2 system? Would a seperate set of (cheaper) cooling fans work the same? I'd like (if I decide to get VRx amps) to have the end caps for it, can I get them without the MAC2's?

 

Sling, if you're going to get the VRx amps and pay good money for them why skimp on the fans...Besides you really only need the fans if you run the amp in Class A mode or 2 ohms bridged mono or 1 ohms stereo.

BTW Adam I didn't pay nearly those kind of prices for my Fan Kit & Mac & Class A module, if I remember right it was about $375 + tax for all three together....I'll check if someone really needs to know.

 

Oh and Sling those fans are pretty sophisticated...micro processor controlled off an output on the circuit board, which varies the speed of the fans according to teprature at the heatsink.

 

The ACB-1 kit has a dash mounted switch that allows you to switch the output stage between class A/B and pure class A. Having a switch for this is a good idea because of the amount of heat that running Pure Class A creates. Even with my fan kit installed, I don't run the amp in Class A mode all the time. It generates a ton of heat!

Here is why: The Class A circuitry essentially turns the output stage ON approx. 50% ALL the time. So if you have a 100 watt amp, it will be running 50 watts continuous through a kind of bypass circuit in the amp.(I'm simplifying this so it's easier to understand) The benifit is in switching noise. Because the amp is always ON, it doesn't "switch" as audibly from 0 current to varying degrees of ON current. There is a lot more to Class A circuitry that I have described above, but I think that this simple illustration shows just how much of difference in heat this bias creates.

Do you need the MAC-2 kit to run the amp with the Class A kit? NO, but I wouldn't advise it. I've forgoten my switch on quite a few times and have heard the cooling fans ramp up to disapate the excess heat.

Why is the MAC-2 so expensive? Well it's more than just a couple of fans. It's actually a thermal monitoring system with fans. It hooks into the VRx temperature sensor circuitry, and initiates the fans to varying degrees when certain temperatures are reached in any one of 3 areas of the amp. The VRx internal temperature monitoring circuitry watches the power supply temp., the driver stage temp., and the output stage temp. When any one of these 3 overheat, the amp can go into thermal protection mode. The MAC-2 kit taps into this circuit and has an infinitely variable fan speed control depending on how warm the amp is in any one of those 3 areas. Usually mine come on when I'm playing music loud, or when I have the booster circuit turned on for a while. To date, I've never heard the fans ramp up to full speed for any prolonged period of time. The heat sink on the amp does a very good job. The MAC-2 kit keeps your amp cooler, and this will prolong the life of every component in the amp. It's a cheap insurance piece for a very expensive amp.

Yes you could use your own fans, but they would need their own power source, and they wouldn't fit in the end cap very well. You'd have to see a kit in peson to appreciate it. It's a very well engineered piece.

For those wise ones out there that are thinking of pluging in their own fans to the fan power output on the amp, it doesn't work. You need the MAC-2 module to initialize the output.

Yes you can get the endcaps without the MAC-2 kit, that is how they come.

I've actually seen one install that used a couple of endcaps to make a mini fake VRx amp.

Hope this answers your questions Sling.

If anyone else has any questions, fire away. I've got a "few" of the optional modules and have enjoyed pushing my amps pretty hard.

Adam

 

Great info Adam, I didn't know about the three different spots it reads the temp at...then again I didn't have a chance to read the entire manual which is as long as a book btw

 

islandphile, those are the MSRPs of those units. I didn't pay that either, but it gives a point of reference.

 

So what kind of sonic differences are you hearing when flip-flopping between a/b and class a?

 

Right on, thanks for the input!