Crest amp in the house - oh and PR18 update (1 Viewer)

[Vince Bray]

Talked to John J on thursday. The baskets have arrived in Cali from china He expects them friday or monday, will assemble the PRs, and hopes to start shipping friday!!!
HCIT?
All the posts about Crest amps were right on. Got a CA6 off ebay and it rocks. I have it hooked up to my wife's old bose in the garage and it makes them sould good! (tweeters still suck) Have only had a little time with it but I am very pleased. It is traditional toroid power supply and the build is first-rate.
I was only unsure about one thing but the more I think about it, I think it will be an advantage. The amp rolls off steeply somewhere below 20hz and has aggresive dc blocking facilities. I called Crest to see if the freq could be reduced, but they said it wasn't practical. The engineer said "imagine if the thing goes DC on you it will be 108 volts at 20 amps. Your speaker cone will go out, and not come back." Good enough for me. It made me remember the scene from Back to the Future Running an HE15 should produce ~>114db from ~20hz on up, 115db from 30hz up. I think this will be a good match since the amps power rating lines up pretty well with the drivers linear range.
Anyway, the amp specs:
600 wpc at 1khz into 4ohm
500 wpc 20-20k into 4ohm
1200 wpc 20-20k bridged/4ohm
damping >400
input sens. at 8ohm .775v
I chose this amp because the fans are standard 80mm x 25mm just like the ones in your pc. there are two, and speed controlled. What I didn't know is that they're 24v. Took awhile to find quiet, high volume 24v fans, but they're coming. In a cabinet it should not be a problem with the quieter fans. I may also put a resistor in series to get the idle fan voltage down to the absolute minimum the fans can take 10v instead of the 12.5v they do now. After all, the PA amps are spec'd to outdoor operation at about 105 degrees max, and this one will be pampered...
There are two models of the CA series, and this is the older one. It has a little less complicated protection circuitry, probably good for our use. The V series amps are rated down to 10hz, but they have a 110cfm fan that might be very challenging to tame unless you have a seperate equipment room (one day).
Now I need to work on the DIY 3 band parametric eq...
Vince

 

[Brandon B]

Out of curiosity, whatcha pay for it? I'm looking for somthing to run a SAL SB10 4 ohm for a center channel bass module in a 3 foot sealed box. Needs to cover about 25Hz to 250Hz with 4th order LR rolloff highpass. SB10 is 500 watts max so it sounds like a good match.
BB

 

[Bob Sorel]

The V series amps are rated down to 10hz, but they have a 110cfm fan that might be very challenging to tame unless you have a seperate equipment room (one day).

Nope....that's normally not the case. I have a rack of 5 VS-900's sitting right on the side of me and I can barely hear a peep from them, with all 5 of them running at the same time! The fans are 2 speed, and stay on low under most circumstances, and are so silent that you have to put your ear right up to them to know that they are even running at all. The only time they shift into high gear is when I am pumping all 10 channels (7 channels plus my front three are biamped) at full volume, playing hard rock music at around 110 db at 12 feet, but with that volume playing you can't hear a person shouting in your ear, so the fan noise is inconsequential
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STOP DVI/HDCP/5C/DFAST!

 

[Vince Bray]

Brandon,
They typically go for about $450 on ebay w/o shipping
Bob,
That's cool, (no pun) should've asked you! The CA6 is making a fair amount of noise but the fans are old, etc. Think it will be better with some very quiet fans. I based this assumption on specs for the larger fans that I've seen, but there are some really quiet fans out there, it's just a challenge to find them. Again, can't say enough good about the Crest product. Very clean, and like you I would LOVE to be running my mains, etc on these puppies.
Vince