Please educate me on Class D Power Amps

Will Kelly · #1 12-31-2010, 03:01 PM

Alright, I am getting rid of the dinosaurs I've been lugging around and going to small, class D heads.

I have an Acoustic image Clarus 2 I've owned for a long time, and I have a GK MB200 on order for giggles.

What I'm looking for is a class D (read light-weight) power amp to supplement either of these for when I need the horsepower. I run two Berg 1X12's and sometimes an SWR 1X15 with one of those twelves.

What's out there and available? I've been reading up on the SWR amplite, it seems a little short on the power goals I want and a little pricey. Peavey has the IPR series, but I really don't need something thats two channel and non-bridgable, although the price and power ratings are attractive.

I would be happy with 600-800 watts into 4 ohms.

Adding a power amp to either of the amps will basically make them a glorified pre-amp, correct? The wattage doesn't get added together, right?

Any suggestions?

videomagician · #2 12-31-2010, 03:12 PM

I've been looking at the Peavey IPR-1600 for running monitors/PA and I read on the Peavey forum where you can build a cable that will allow you to bridge both channels of the amp. You can snoop around in their forum here and probably find the same information.

I have been using a Carvin BX500 since July and really like the amp, even though it has cut out a couple of times momentarily on gigs. I'll be sending it back to Carvin for them to check it out.

Good luck!

David

parsons · #3 12-31-2010, 03:24 PM

http://cgi.ebay.com/SOUNDTECH-PS802-...item27b75db603

But dont pay that price. I snagged one off of ebay for alot cheaper. Email the seller and see if theyll negotiate.

In bridged mode, this thing will KILL a cab.

ErnieD · #4 12-31-2010, 03:32 PM

Doesn't just have to be Class D. The Markbass LMII/III models are class A/B, IIRC. The F1 is class D. These models will only offer you 500 watts @ 4 ohms. But there are other MB heads that can offer you more watts. And do a search on Genz Benz' 9.0 head, many like that one for the added watts it offers at 4 ohms.

I've used my F1 and LMII with my Crown Coredrive XLS1500 power amp as a pre. The head you choose will work as your preamp, I believe this overrides the internal power amp of the head. So the external power amp, my Crown, supplies all the watts.

In my case I can get 1050 watts bridged @ 8 ohms. I'm using this setup tonite for my NY's eve gig w/Epifani UL410-II, 8 ohm cab. If I've mispoken here, someone may correct me.

98dvl · #5 12-31-2010, 03:37 PM

I'm sure you have your reasons, but I'm curious... Why do you need 600-800 Watts of power? What kind of gigs are you playing?

I really can't understand why anyone needs that much stage volume, unless you're playing on a huge arena stage, or have no PA support.

My GK800RB and Ampeg 4x8 is almost overkill for most of the stuff I do around Austin.

fesojstubb · #6 12-31-2010, 03:40 PM

I have one of the old AI Clarus II Series 3 that runs 400/500/900 at 8/4/2 ohms. I bought it used two years ago for about $500. When I need to get a dirtier sound I run into an Aguilar Tonehammer pedal then into the AI-either the preamp or in the effects loop. I has a good tube emulation that is less edgy and more musical than the Sans-amp pedals. I like a warmer sound like Billy Cox. The pedal does have a mean distortion channel to get that sound if you want it.

JB

ErnieD · #7 12-31-2010, 03:44 PM

don't even get into that query here. You'll get so many replies "as to why" well into the new year.

I don't get PA support and in this medium size club I'm at tonite I'll be using my Crown CD XLS1500 amp w/Alembic F-1X pre, bridged @ 1050 watts into my 8 ohm UL410-II. I may not need all them watts but I'm sure this band will get loud later and I'll have ponies to spare without stress.

Now I also use my 500 watt heads often and do fine. Just horses for courses. Just gotta know when to pull in the reigns. Peace y'all.

chuck3 · #8 12-31-2010, 04:14 PM

as to "why" - mainly what Ernie said. There's no room in the PA for my bass guitar (although I double on upright and that goes through the PA). So the bass guitar has to "compete" so to speak with guitar, drums and vocals going through two big JBLs in front of the band. You don't need to be playing arenas to want at least 600 watts at 4 ohms, just to keep some headroom. I'm currently using a Genz Benz 6.0 Shuttle with a Schroeder 212 in these situations.

Will Kelly · #9 12-31-2010, 04:23 PM

Yes, mainly headroom reasons. Most of the gigs I do that are loud do have good PA support, but I like the headroom, to me, it does give a fullness of tone thats hard to get sometimes.

The Bergs I use are rated at 300 watts each, and from experience, I know that they love the full wattage. I think 600 watts at 4 ohms is reasonable.

chuck3 · #10 12-31-2010, 04:43 PM

Then I recommend either the Genz Benz Shuttle 6.0 or the LittleMark II, which I think is 575 at 4 ohms. The LM II is no longer a current item but you can get both that the the Shuttle 6.0 at pretty good prices used these days. Next step up would be the Shuttle 9.0 at 900/4 with a begger voicing in the low end I am GAS-ing for one of those, but it's hard for me to argue that I need all 900 watts. Although the Schroeder 212 claims 1000 watts (seems high) so I could at least do it in the name of ... something.

chuck3 · #11 12-31-2010, 04:48 PM

Sorry, 500 watts on the LM II.

Just to get back to your original question, the Genz Benz Shuttle 6.0 and 9.0 are both Class D. Not sure about Markbass. But I am obviously a big Genz Benz fan.

steveksux · #12 12-31-2010, 04:57 PM

The new crown class D, xls1000. Its more watts than you're looking for, but its only 299. Can you find a 500 class D amp cheaper? So why not get more watts?

Randy

Will Kelly · #13 12-31-2010, 05:11 PM

Hey Randy...

Excellent suggestion on the Crown XLS 1000. This looks to be near perfect for what I am looking for.

Any amp with a line out can be run into this, right? The GK head I ordered has a line out, but my Acoustic Image head does not have one. I am assuming I will not be able to run the AI into the power amp, just the GK.

Can someone set me straight on that?

chuck3 · #14 12-31-2010, 05:25 PM

I think you are incorrect. According to the manual for the Clarus 2, it has an XLR direct out. That should work. You may need a cord that's XLR to 1/4-inch, but that's easy.

Will Kelly · #15 12-31-2010, 05:32 PM

Thanks Chuck, you are right! It does have an XLR DI out. Never even thought about that as a signal source for a power amp.

chuck3 · #16 12-31-2010, 05:49 PM

Works for me into hi-power PAs all the time. Don't see the difference with a power amp. It's a line-level signal.

chucko58 · #17 01-01-2011, 12:53 AM

Not all lightweight power amps are Class D. The QSC PLX amps are Class AB or Class H (i.e. linear output stage) but use a lightweight switching power supply. They will be only a little heavier than a full Class D. Unfortunately the PLX 1104 is not bridgeable. A first-gen PLX 1202 is bridgeable and should be readily available used.

(Disclaimer: I own a pair of first-gen PLX amps and am a big QSC fan.)

Jarrett · #18 01-02-2011, 05:57 AM

I have both the Carvin BX500 (supposedly 500 watts @ 2 OR 4ohms @ $369) and Genz Benz Shuttle (supposedly 900 watts @ 4 ohms @ $829) and I find the BX500 to be just as loud. I think Genz Benz overrated the Shuttle a bit at 900 watts, its just not as loud as the rating suggests. I prefer the sound of the BX500 and like its ability to go to 2 ohms, where the Genz Benz cannot. It allows me to run a 4ohm 2x10 and 4ohm 4x10 and move quite a bit of air in a fairly compact package. The Genz Benz can only run either the 2x10 OR the 4x10 which puts it at quite a disadvantage to the BX500 is terms of overall volume. The down side of the BX500 is some say its unreliable. I haven't run into that yet, but have only had it two weeks at this point. Then again you can buy two BX500's for less than one Shuttle 9.0.

ErnieD · #19 01-02-2011, 12:20 PM

I think those issues with the newer Carvin BX500 heads showed up pretty immediately, with shut downs, buzzes/static whatever those issues were. If you've not experienced any of that yet, you're prolly fine.

But I'd play it as much as possible if you're still in the warranty stage to be safe. And are you saying the BX500 @ 4 ohms was louder than the 9.0 @ 4 ohms? If your saying the BX500 is louder at 2 ohms, then you're using two cabs which does not make this a fair comparison.

Then there's the whole lot of other factors such as, the knob placement, EQ settings, etc and all that entails on two different manufacturers amps that may not make this a true A/B comparison. And I doubt you're pushing the exact max of 500 or 900 watts of either amp. But you're ears will always tell you what you prefer regardless of specs.

So go with it and enjoy em both if you like. I use 5-6 different amps/cabs/basses to gig just for the variety they offer tone/weight/fun-factor wise.

Jarrett · #20 01-02-2011, 05:32 PM

Quote:

Originally Posted by ErnieD

And are you saying the BX500 @ 4 ohms was louder than the 9.0 @ 4 ohms?

I'd say they are about equal. Not sure which one is fibbing on their power rating. Either the BX500 is more than 500 watts or the Shuttle 9.0 is less than 900 watts.