What's the best power amp?

**jreynolds2159** · #1 01-20-2013, 07:05 AM

I am moving to separates on my rig and I have been told that "just any power amp" will not do! I am looking at the Crown XTi2002 and using my Genz Benz Streamliner as a pre so will always have a back up power source. Is this power amp going to have what I need? I tour quite a bit and having a second way o power things would be comforting. I love the Genz but I have a Schroeder 1212 4 ohm and a Bergantino HT322 4 ohm and I want to use them both at the same time so that's why I going power amp. Somebody help!

blastjv · #2 01-20-2013, 07:27 AM

Why not just grab a used streamliner and call it a day?

**jreynolds2159** · #3 01-20-2013, 07:33 AM

I thought about that but I can get a New Crown 2002 for about half the price of another Streamliner and I don't have to drop another $80.00 for an amp rack kit!

tekdiver500ft · #4 01-20-2013, 07:56 AM

Crown aren't the "best" power amps, but it will certainly do what you want in this case.

**jreynolds2159** · #5 01-20-2013, 07:59 AM

So what would be a better choice over the Crown? i want to do this right.

tekdiver500ft · #6 01-20-2013, 08:12 AM

I'd look at Crest first, then Alto and QSC if the Crest are too much money. I only use Alto in my sound company, and the sound quality of them is outstanding. The difference between Crest and Alto is there, but most people won't hear it. The difference between Crown and Alto is noticeable.

randyg · #7 01-20-2013, 08:17 AM

Everyone will have an opinion but I bought a Carvin DCM1500 dirt cheap when the new lightweight amps came out and it has been an absolute workhorse. I use an Ampeg SVP-CL pre and a 610hlf cab. It has run bridged at 4 ohms for hours at outdoor gigs in summertime heat and has never given so much as a hiccup. Some amps may have better specs , but I would buy another one in a heartbeat.

tekdiver500ft · #8 01-20-2013, 08:22 AM

Carvin can be very reliable, but he asked what is best. Carvin don't have the clarity of the other amps mentioned.

**CL400Peavey** · #9 01-20-2013, 08:31 AM

It really depends on what features are important to you, and how much you have to spend. The Crest CA9 is a bench mark in terms of power amps, but its not light. The prolight 2.0 is lighter, but there is also a DSP version. Neither may fit in to your budget, and there are other options out there.

randyg · #10 01-20-2013, 08:31 AM

I know the Carvin's specs don't match up to some of the higher priced amps , but it sounds mighty fine for bass to me. But the 70's were very rough on my hearing.

mike phillips · #11 01-20-2013, 08:33 AM

only one choice for a power amp: QSC

**jreynolds2159** · #12 01-20-2013, 08:53 AM

So there is no such thing as a power amp that is not meant for instrument use and only for PA?

1958Bassman · #13 01-20-2013, 09:05 AM

It's not just a simple matter of "What is the best amplifier for me?".

If you look for power amps, choose something that will drive a 2 Ohm load all day long. I can't think of a decent amp that won't provide wide bandwidth, so that doesn't even matter. What matters is current. A strong power supply, good/durable output devices (MOS-FETs are a good choice because they self-regulate, in order to avoid thermal runaway). If it has more dynamic headroom, that's nice, but high peak power levels is what gets a lot of people in trouble- they think compression and limiting will remove dynamics from their sound when these were originally designed to avoid problems with damaged speakers in recording, broadcasting, live performance or fixed installations.

A compressor or limiter won't have a negative effect on the sound if it's set correctly. Equalization won't lead to damaged speakers if it's set correctly. Separates are great, but IMO, not enough people buy equipment knowing exactly what they need, what the equipment is capable of and what will be a reliable rig.

If someone wants loud, adding a ton of power to one or two speakers isn't the best way to achieve this. Sure, amps can develop 1000W and more but when speakers receive this amount, the voice coil will become hot and one fundamental of physics is that a conductor's resistance will increase as its temperature rises. That's the cause of 'thermal compression', if you have wondered. The effect of this is that either the SPL drops over time or the speaker will fail. Put your hand on a speaker magnet when you have cranked the snot out of the rig for an hour- you'll be surprised.

More output is best achieved by high power, for cleaner signal and more speakers.

As far as speakers, they have to be given signal that they can deal with, not what's outside of their "comfort zone". Going outside of their comfort zone makes speakers fail- they either shake apart or experience thermal failure.

Signal- bass amplification requires limiting dynamics and frequency range. If a bass reflex (ported) cabinet is used, sending frequencies that fall below the port tuning frequency will result in speaker failure and bad sound. Bass players don't need 20Hz, or below. For that matter, we don't need much below 50Hz. Bass reflex cabinets produce more SPL with a given input signal but they have their own problems. The output from a sealed cabinet (acoustic suspension) is lower, but cleaner and better damped, unless the cabinet is too small. However, the maximum output SPL absolutely needs to be known. Without knowing that, it's impossible to find a solution that will work because the amp and speakers will be run far harder than what will allow them to live long.

If I wanted to build a rig with separates, I would find a preamp that sounds good and choose a power amp that is more powerful than I would need and it would probably have crossovers and limiting built in, possibly equalization. Crown's XLS series has this.

Here's a link to technical topics that may help-

http://www.crownaudio.com/ampinfo.htm

If you use the XTi amps, don't use the subharmonic synth feature unless you want to puke a low of speakers. If you don't plan to use strong subwoofers, this is not what you want or need. This is for theaters and FOH, not a live bass rig. Not only will having extreme low frequencies require more power and different/more speakers, it will really screw with the mix- subharmonics will go into every mic and transducer on the stage, whether you want that, or not. It can't be avoided. If you send sub-harmonics through normal speakers, they will puke, period.

If you use everything else in this series of amplifiers, you shouldn't have any problem with speaker durability [i]if the controls are set correctly.

If you look at a brand like QSC, their GX7 would be a good choice (or the GX5 if you don't need as much power).

chienmort · #14 01-20-2013, 09:09 AM

Some if you could get all tube/valve power amp, its limitations would contribute to your tone. With solid state PA rigs some are audiophile quality and I don't think you would go too far wrong with any of those mentioned.

Crown/Amcron were the first big amps but the others have all caught up. In hifi terms they may all sound a little different but with a bass? Not a lot.

One thing though, a built in hi pass (sub sonic) filter would make sure your cabs don't poke out the front when you either drop your bass or over EQ the bottom end.

1958Bassman · #15 01-20-2013, 09:12 AM

Quote:

Originally Posted by tekdiver500ft

I'd look at Crest first, then Alto and QSC if the Crest are too much money. I only use Alto in my sound company, and the sound quality of them is outstanding. The difference between Crest and Alto is there, but most people won't hear it. The difference between Crown and Alto is noticeable.

Is this difference in the clarity of the highs/mids and/or headroom? Can you be specific WRT how one would be better than another for bass guitar?

Bassmec · #16 01-20-2013, 09:41 AM

Best power amp.
Amcron have a range of low cost lightweight amps and very hi quality amps called macrotech. They are not the lightweight ones though, so I think you need to specify as to whether we are talking about a fan cooled lightweight amp or a fan cooled amp with a conventional heavy transformer or a really high quality noiseless amp, no fan cooling.
Like a Bryson 4b with its 20 year no quibble guarantee.
Which is very obviously the best of all, except in the weight department.
So Is this thread really about what's the best lightweight fan cooled amp?:

I think it's this one myself, but fan cooled wise, give me a full fat Macrotech 3600 any day. I ain't worried about what it weighs.

tekdiver500ft · #17 01-20-2013, 09:57 AM

1958Bassman makes some really good points, and I'd seriously look at the QSC GX7.

Bassman, I consider the Alto, QSC and Crest rigs superior to Crown mostly due to the clarity in the mids and their well-balanced output. All three of them seem to under rate their amps, and I've seen them all perform beyond rated specs. I didn't really think about specs in this case, though. I've used all these, and the Crest are the most musical to my ear. I like the way they handle being pushed, I love how they treat receiving a distorted signal and how clear they are the rest of the time. They are also amazingly well-balanced, with no undue emphasis of any particular frequency. When EQing for a particular room, I have to do less with Crest than the others, with Alto and QSC coming very closely behind. So, for me, it's sound quality first, ease of use second, headroom third, and specs a distant fourth. If I could afford/justify it, I'd only use Crest power amps. As it is, I stick with Alto because I'm used to it, and I know how everything will work together. Were I not so heavily invested in Alto, I'd consider QSC, too.

**jreynolds2159** · #18 01-20-2013, 10:59 AM

Wow, that's a lot of great info. I guess I am more interested in the new class D stuff because I bought my Genz Streamliner because of the weight and I am touring constantly so that's kind of important. I have picked up a Crest before and I did not enjoy it all that much but they sound great. The weight and a great price from a friend is what pulled towards the Crown XTi2002 and the power is just right for 2-4ohm 1,000 watt cabs.
I mainly wanted to make sure I wasn't buying a power amp that was not suitable for an instrument amp
Thanks for all the help and expertise

**CL400Peavey** · #19 01-20-2013, 11:10 AM

Seriously look at the crest prolite 2.0 and the peavey IPR 1600. Same amp for the most part, the crest has a few more features, but both are great for what they are.

Binkybubba · #20 01-20-2013, 11:11 AM

I agree with the Crests, used own a sound and lighting production company and used lots of Crest but had a great backline set up that I also used for personal and got nothing but good reviews from rewpected pro's. I used a Carver (not carvin!) PM1200 with an Eden Navigator pre-amp and a variety of cabinets, always with good results. Very, very clean, very quiet, with gobs of warmth and tons of headroom. They are known for audiophile set ups but are very much at home as a PA amp. Harder to find now but something circa 1990ish is your best bet. They look great as well and have superb protection circutry. You are looking for the units with a bit of a resessed panel section if I recall properly. Totally worth trying, you will always get your value back if you find it's not for you.