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Title: Which Amp/s for reliability/performance
Post by: Allan James on January 09, 2011, 10:20:27 PM
I have 2 EV Zx3s and 2 TH-Minis that I am looking to power with either a Crown Itech 4/5000HD, tops one side and subs the other or use two of the new XLS 2000 amps bridged, one for the tops and the other for the subs. For basic setup/protection and limiting, the Itech or XlS DSP would seem to be adequate, the main thing I would be missing with the XLS amps would be the ability to delay tops/subs. Is there anything I am missing or making the wrong assumptions about, including reliability of bridged amps. The XLS option would be cheaper. Thanks, AJ
Title: Re: Which Amp/s for reliability/performance
Post by: Ivan Beaver on January 10, 2011, 09:15:48 AM
Allan James wrote on Sun, 09 January 2011 22:20

I have 2 EV Zx3s and 2 TH-Minis that I am looking to power with either a Crown Itech 4/5000HD, tops one side and subs the other or use two of the new XLS 2000 amps bridged, one for the tops and the other for the subs. For basic setup/protection and limiting, the Itech or XlS DSP would seem to be adequate, the main thing I would be missing with the XLS amps would be the ability to delay tops/subs. Is there anything I am missing or making the wrong assumptions about, including reliability of bridged amps. The XLS option would be cheaper. Thanks, AJ

Several years ago when the XLX first came out we installed a fair number of them.  We started having a lot of failures-so we stopped using them.  I don't know if they have changed anything or not in the current models.

I have very little experience with the Itech amps-except one situation that had a REALLY weird hum problem that I was not able to figure out.  I was completely stumped Confused .  But that is only my opinion based on very limited experience.
Title: Re: Which Amp/s for reliability/performance
Post by: Tim McCulloch on January 10, 2011, 11:09:14 AM
We've been very happy with our I-Tech 6000/8000 and found them to be no more problematic than our MacroTechs.  Our old iron Crest 8001s, however, have been the most reliable amps we've owned.  To say we have dozens of each would be accurate.

You can't really compare the I-Tech to the XLS; they are leagues apart. If you're looking at IT5K-HD (or original IT), you should be looking right past the XLS Drive Core.  Also, I'm not a big fan of bridge-mode operation.  Get amps big enough to power your rig w/o bridging.  Power is cheaper than it's ever been.

Also DSP is relatively cheap now, if you went with plain amps, but for the price of re-certified I-Techs you get a very good amp with very good DSP.  If you go with Crowns, download and install Harman System Architect.  It has capabilities you'll never need/use, but it's masterful at setting up, monitoring and controlling your Crown amps and other Harman group products.

Have fun, good luck.

Tim Mc
Title: Re: Which Amp/s for reliability/performance
Post by: Steven Warner on January 10, 2011, 06:33:29 PM
Ive always liked the sound of a crown even low line ones. that being said crown is the only brand of amps that have ever left me stranded mid-gig on several occasions. I have never owned an itech, I have read good things here on psw. If your going to go the bridge route stick to qsc or even if your not going to bridge you cant go wrong with qsc.
Title: Re: Which Amp/s for reliability/performance
Post by: thomas jones on February 14, 2011, 09:00:21 AM
Am I hallucinating or are there alot of Crown failures? Maybe it's the odds because there are so many and the ones that fail are a small % of the number in use. I know everybody hates the B word but I have 2 EP2500's and an EPX 3000 and they work first time every time and I always get compliments on the sound from 2 old SR4735's & 2 SR4718's. I spend the extra money on hallucinogens.
Title: Re: Which Amp/s for reliability/performance
Post by: Chuck Simon on February 14, 2011, 09:29:11 AM
I have been running a few QSC Powerlights for over 10 years now(maybe 15?), and amp failure is something I don't even think about.  Now, I don't run them bridged and rarely at 2 ohms.  I also have a few of the PLX series of various ages and again, no failures.  Needless to say I am a big fan of QSC amps and they are the only brand I will buy or recommend.
Title: Re: Which Amp/s for reliability/performance
Post by: John Roberts {JR} on February 14, 2011, 12:00:42 PM
thomas jones wrote on Mon, 14 February 2011 08:00

Am I hallucinating or are there alot of Crown failures? Maybe it's the odds because there are so many and the ones that fail are a small % of the number in use. I know everybody hates the B word but I have 2 EP2500's and an EPX 3000 and they work first time every time and I always get compliments on the sound from 2 old SR4735's & 2 SR4718's. I spend the extra money on hallucinogens.


Don't read too much into a small sample of anecdotal reports (positive or negative). Any major amp manufacturer with significant product in the field and in use will experience failures.

Regarding your amps, they are based on a pretty well respected design, albeit somebody else's, so should sound ok. As long as your amps aren't clipping the "sound" should be dominated by the loudspeakers.

JR
Title: Re: Which Amp/s for reliability/performance
Post by: Greg Cameron on February 14, 2011, 12:19:36 PM
Tim McCulloch wrote on Mon, 10 January 2011 08:09

Our old iron Crest 8001s, however, have been the most reliable amps we've owned.  To say we have dozens of each would be accurate.


Couldn't agree more. I have a love hate relationship with my 8001s. I love them because they're super reliable and seem to produce more burst power than the specs would indicate. IOW, they seem to have more punch than other similarly power rated amps for low frequency duty. I hate them because they're 80 lbs. each. At least now they have a home where they don't have to be moved Wink

Greg
Title: Re: Which Amp/s for reliability/performance
Post by: Moby (Mike Diack) on February 14, 2011, 02:08:45 PM
John Roberts  {JR} wrote on Tue, 15 February 2011 06:00

thomas jones wrote on Mon, 14 February 2011 08:00

Am I hallucinating or are there alot of Crown failures? Maybe it's the odds because there are so many and the ones that fail are a small % of the number in use. I know everybody hates the B word but I have 2 EP2500's and an EPX 3000 and they work first time every time and I always get compliments on the sound from 2 old SR4735's & 2 SR4718's. I spend the extra money on hallucinogens.


Don't read too much into a small sample of anecdotal reports (positive or negative). Any major amp manufacturer with significant product in the field and in use will experience failures.
JR


I have come to the conclusion that the trick with Crown is to never buy anything in the first 2 years on the market - give them time to iron out the bugs on other guineapigs/customers/betatesters, issue the ECOs and get it right. I realise Crown has a huge amount of embedded customer loyalty in the USA (probably built up by the MA series bricks) and because the service turnaround is short and sweet, believers are prepared tolerate teething problems, but in other parts of the world, where shipping costs real money, the shine comes off real quick when a new whizzy amp like the i-Tech has close to a 100% failure rate (I know this because I'm the bloke who had to fix them)in the initial issue. This is NOT a small sample in my part of the world.
M
Title: Re: Which Amp/s for reliability/performance
Post by: jeff harrell on February 14, 2011, 02:22:03 PM
i have the antique QSC Series 3 3500 and 3800. no problems and i run them in bridged mono at 4 ohms. i know of some antique Crown DC300 amps still in use. i have ben told the Crest 8001 or something like that is very reliable. i saw a lot of "blode up real good" Phase Linear amps. i have heard that the crown macro tech acts weird when driving a 4 ohm load. i dont use crest, i use colgate with floride.
Title: Re: Which Amp/s for reliability/performance
Post by: John Roberts {JR} on February 14, 2011, 05:06:04 PM
Moby (Mike Diack) wrote on Mon, 14 February 2011 13:08



I have come to the conclusion that the trick with Crown is to never buy anything in the first 2 years on the market - give them time to iron out the bugs on other guineapigs/customers/betatesters, issue the ECOs and get it right. I realise Crown has a huge amount of embedded customer loyalty in the USA (probably built up by the MA series bricks) and because the service turnaround is short and sweet, believers are prepared tolerate teething problems, but in other parts of the world, where shipping costs real money, the shine comes off real quick when a new whizzy amp like the i-Tech has close to a 100% failure rate (I know this because I'm the bloke who had to fix them)in the initial issue. This is NOT a small sample in my part of the world.
M



Your experience, while biased toward over exposure to failures is surely more relevant to a discussion of reliability.

While a minor distinction, design faults are only a reliability issue when left uncorrected.

Do you service all brands? I seem to recall from past discussions that you service enough of them to make a general comparison.

I have been involved in major amp roll-outs before and it requires a large amount of time, effort, and luck to dodge the gremlins that can bite you (I have bite marks in my tender places).

The crown I-Tech problems were well reported and we can debate the difficulty of shutting down for weeks or months to re-engineer a problem assembly after the production lines have been turned on full.  Damned if you do, damned if you don't.

I'm old enough to recall the general advice to never buy a new car in the first months of production.  Probably still true today.

JR

Title: Re: Which Amp/s for reliability/performance
Post by: jeff harrell on February 14, 2011, 07:23:53 PM
Greg Cameron wrote on Mon, 14 February 2011 09:19

Tim McCulloch wrote on Mon, 10 January 2011 08:09

Our old iron Crest 8001s, however, have been the most reliable amps we've owned.  To say we have dozens of each would be accurate.


Couldn't agree more. I have a love hate relationship with my 8001s. I love them because they're super reliable and seem to produce more burst power than the specs would indicate. IOW, they seem to have more punch than other similarly power rated amps for low frequency duty. I hate them because they're 80 lbs. each. At least now they have a home where they don't have to be moved Wink

Greg

yeah , and the QSC 3800 weighs 75 pounds. oooohhhhhhh my back ! carry it on your shoulder or gitta rack ! i need the back rack now !
Title: Re: Which Amp/s for reliability/performance
Post by: John Watson on February 14, 2011, 11:34:48 PM
I just got rid of a QSC RMX 2450, that once out of warranty wouldn't stay working for more than two months at a time.

You can always get a lemon with any amp. My best experience has been with AB Internationals (remember them?) and Crest. I also had some Macro's which held up fine. But for some reason QSC's have always been problematic for me.
Title: Re: Which Amp/s for reliability/performance
Post by: MARK PAVLETICH on February 16, 2011, 02:03:05 AM
In my experience of using power amps over the last 40 years, two brands stand head and shoulders above the rest for reliability. QSC and Peavey. Yes I have had both of these fail ocasionally but not very often, and when they did they were fixable by local techs. I had a good run out of the non lightweight Carver PM series as well, real tough workhorses.

The one thing I must say about the Peaveys is that the only reliable ones were the heavy ones........Being an earlier adopter of Lightweight amps in the 90's Peavey paid the price for a less than mature technology. I have never used the modern Chinese made Peaveys so I cannot comment.

QSC's have been reliable, both the heavy and the lightweight ones, both US and Chinese made. I also must note that QSC's and Peaveys have both also given me a lower rate of speaker failures over the years so I guess I have a winner,,,,QSC !!
Title: Re: Which Amp/s for reliability/performance
Post by: Glen Kuykendall on February 17, 2011, 01:19:52 AM
I had a bunch of Crown amps back in the 80s-90s, but when I recently built a new small club system I went with QSCs and have been very pleased with them. For tops I run a pair of EV SX300s off a PLX1804, and just recently started using just one side of that amp for a monitor mix and both the EVs on the other channel. I run a 2nd PLX1804 for two more monitor mixes. Then I run my pair of Danley TH-Minis in parallel on one bridge PLX2502. So far with about 10 gigs on the system all has been well and sounding great. For HPF filters, EQ, limiters and such I started off with a DR260, but moved to a Xilica XP-4080 unit (w/ethernet) as I could run my mains, plus 3 monitor mixes off of one unit. With a cheap wireless router velcroed into my amp rack hooked to the Xilica, I can tweak all the PA processor settings via wireless using my cheap little HP Netbook.
Title: Re: Which Amp/s for reliability/performance
Post by: Tim McCulloch on February 18, 2011, 12:47:06 PM
thomas jones wrote on Mon, 14 February 2011 08:00

Am I hallucinating or are there alot of Crown failures? Maybe it's the odds because there are so many and the ones that fail are a small % of the number in use. I know everybody hates the B word but I have 2 EP2500's and an EPX 3000 and they work first time every time and I always get compliments on the sound from 2 old SR4735's & 2 SR4718's. I spend the extra money on hallucinogens.


The Crown I-Tech failures (the spectacular ones, anyway) stopped 4 years ago.  There are occasional minor issues, but that's true for every make and model we own.  Out of around 50 I-Techs, we've sent 3 to Crown for a "funny noise", not a Flame Linear moment.  We have had no spectacular failures, ever.  We also had to have 1 MacroTech 3600 (out of 24 Old Iron MTs, now replaced with ITechs) serviced a couple years ago.  Overall, we're very happy with the reliability of Crown, Crest (at least the old stuff) and QSC (although we have only a couple QSC amps).  All of "the majors" make good stuff.

FWIW, we also had to repair 3 Crests in the last 2 years, but most of them are close to 20 years old.  Realize we own 100+ amps that vary in age from a few months to older than some of the posters here.

I've been a weekend warrior, too, schlepping gear in a van and was always worried about a failure because I either had no space or no money for spares.  That was 25 years ago, though, when a "big" amp was 400w/ch @ 4 ohms and weighed at least 60#.  Today there are many choices that weigh less, are smaller and more affordable than ever.  At today's prices a weekend warrior would be foolish to not have some kind of back up amp.  Sound Image carries spare I-Techs... exactly *2* for an arena sized rig, one for monitors and one for PA.

Have fun, good luck.

Tim Mc