Members Norton666 Posted June 8, 2007 Members Share Posted June 8, 2007 I recently replaced my Behr power amps with Crown XTI power amps. I just hooked them up for the first time yesterday and the XTI2000 , which I want to run a pair of Dual 15"s full range, is giving me fits. I set it to run with the DSP off and what is happening is the channel 2 volume control is not doing anything at all and the channel 1 volume control is adjusting volume through both speakers. It is running as if the channels are summed, but the amp is set to stereo and it is not running any kind of DSP. I called Crown directly( I am a dealer, but I have NO experience with these amps) and they walked me through a bunch of stuff and told me there was something wrong with the amp and they overnighted me a new one. I just hooked it up and it is doing the exact same thing!!!! I have tried switching inputs, not linking the power amps, storing blank presets etc. It always does the same thing. Also, I am running an XTI4000 on the Sub Synth preset for a pair of Dual 18" subs and i just took the amps to about noon and put the masters on the board at 0 and I was clipping. It seemed way too early for these amps to be clipping. Am I doing something wrong here? Link to comment Share on other sites More sharing options...
Members Norton666 Posted June 8, 2007 Author Members Share Posted June 8, 2007 anyone? Link to comment Share on other sites More sharing options...
Members aw_dee_o Posted June 8, 2007 Members Share Posted June 8, 2007 Unfortunately, i can't help you as i'm not familiar with these specific Crown amps. Having said that, i've run into problems with Crown's clipping long before other similarly rated but better built amps do. I think that a LOT of this has to do with the scrawny ass power supplies and filter caps that Crown uses. This results in the rail voltages sagging under heavy load. Less available voltage ( due to the sag ) translates to less available power, resulting in clipping. Noticeably bigger filter caps may help this problem, but would strictly be a band-aid at best. I have no idea what's going on with both channels working from one gain control. Since both amps are doing the same thing, sounds like there is some type of setting that is being overlooked. Ever think that your moniker is cursed and bringing you bad luck??? Sean Link to comment Share on other sites More sharing options...
Members tom titus Posted June 8, 2007 Members Share Posted June 8, 2007 Have you downloaded the most recent software update for the amp? try here for more information crownaudio.com/forums/ Link to comment Share on other sites More sharing options...
Members aw_dee_o Posted June 8, 2007 Members Share Posted June 8, 2007 When i posted technical questions to the Crown forums, i never got ANY responses from them or anyone else what so ever. As a side note, if Crown drop-shipped him an amplifier the next day from their warehouse, i.e. not an amp sitting on the shelf at some shop or distributor, one would hope that they would have not only tested it, but made sure that it had the latest software available. Then again..... Sean Link to comment Share on other sites More sharing options...
Members Zeromus-X Posted June 8, 2007 Members Share Posted June 8, 2007 Not the post I want to read seeing as how I just ordered an XTi 2000 to replace my dead Yamaha literally two hours ago! Link to comment Share on other sites More sharing options...
Members Not Serial Posted June 8, 2007 Members Share Posted June 8, 2007 could the inputs be set to either bridged or parralel? the only issues with XTI amps i have heard of are much like the itechs where the input pots get flakey once and a while, or the display acts strange. Link to comment Share on other sites More sharing options...
Members ned911 Posted June 9, 2007 Members Share Posted June 9, 2007 If your running the sub-synth preset I believe that one has the amp bridged. When you bridge the amps the Channel 2 volume control is disabled. Link to comment Share on other sites More sharing options...
Members W. M. Hellinger Posted June 9, 2007 Members Share Posted June 9, 2007 Are you possibly using a Speakon cable set-up for bridge-mono operation? Link to comment Share on other sites More sharing options...
Members ja_remi40 Posted June 10, 2007 Members Share Posted June 10, 2007 i had the same problem when i first got my xti poweramp...i pretty much just messed around with the presets...like i chose stereo,disabled limiting/crossover/eq..and used parallel on the last part...its been working great for me though...even the xti1000 is much louder/cleaner than i thought it would. Link to comment Share on other sites More sharing options...
Members agedhorse Posted June 10, 2007 Members Share Posted June 10, 2007 Having said that, i've run into problems with Crown's clipping long before other similarly rated but better built amps do. I think that a LOT of this has to do with the scrawny ass power supplies and filter caps that Crown uses. This results in the rail voltages sagging under heavy load. Less available voltage ( due to the sag ) translates to less available power, resulting in clipping. Noticeably bigger filter caps may help this problem, but would strictly be a band-aid at best.Sean Bull{censored}. Link to comment Share on other sites More sharing options...
Members agedhorse Posted June 10, 2007 Members Share Posted June 10, 2007 Doublecheck that there are no jumper links installed IF that amp comes equipped with barrier strip inputs. Also, I would be suspicous as Mark indicated, that you are possibly using the bridged out or a cable set for bridge operation. Crown's behaviour may be different if only one channel is being driven that way. Link to comment Share on other sites More sharing options...
Members agedhorse Posted June 10, 2007 Members Share Posted June 10, 2007 i had the same problem when i first got my xti poweramp...i pretty much just messed around with the presets...like i chose stereo,disabled limiting/crossover/eq..and used parallel on the last part...its been working great for me though...even the xti1000 is much louder/cleaner than i thought it would. Messing around with it to fix the problem... lucky you didn't end up with a speaker problem as well. Link to comment Share on other sites More sharing options...
Members aw_dee_o Posted June 10, 2007 Members Share Posted June 10, 2007 Agedhorse: Your "bull{censored}" response above tells me that you've never actually measured the operating voltages of an amp that is being driven hard under actual operating conditions. If you had, you would know that my statements are not "bull{censored}". Doing so might provide you with better insight as to why certain amps clip harder, more frequently, suffer from reduced dynamic headroom, lack speedy recovery once driven into saturation, don't "double down" as impedance is halved and sound "different" when trying to drive various reactive loads. Not all amps are equally well designed, load stable or linear in amplitude frequency response. Changing the load that the amp sees can alter a multitude of electrical performance criteria to a very measurable extent. When i presented hard data pertaining to a specific Crown amp that i was having problems with in regards to clipping, nobody from Crown wanted to touch the subject when posted on their forums. Doing so would have acknowledged that such a problem could exist with one of their products, let alone what might have been a good portion of their product line. Sean Link to comment Share on other sites More sharing options...
Members W. M. Hellinger Posted June 10, 2007 Members Share Posted June 10, 2007 If your running the sub-synth preset I believe that one has the amp bridged. When you bridge the amps the Channel 2 volume control is disabled. Part of the reason I'm having a tough time warming up to the digital revolution. When my "pard" Tom bought all those Crown I-Techs... and was setting them up for the first time, some wrong button got inadvertently pushed and locked up something like 4 of them... locked up so bad they had to go back to Crown for a lobotomy. My Geo car has a computer and a few sensors. One of the sensors had a problem... which just completely snafu-ed the Geo car, unless the computer went into default mode, then the Geo car ran like a top... but as soon as the computer started trying to reason with the confusion coming from the defunct sensor, it gagged, puked, fouled plugs, and burned outrageous quantities of fuel. I wished the computer wasn't so "smart"... but then I probably wouldn't have gotten on changing the sensor as quickly if the computer hadn't been so smart. The computer seemed hell-bent on making my life completely miserable till the faulty sensor was changed out. Why can't they just put "default" buttons on computer stuff where the default button puts the computer into stupid mode, allowing the device to basically function "normally" (straight-forward) and we can kick it up a notch after we read and fully digest the 672 page user Link to comment Share on other sites More sharing options...
Members smitty0069 Posted June 10, 2007 Members Share Posted June 10, 2007 Having said that, i've run into problems with Crown's clipping long before other similarly rated but better built amps do. I think that a LOT of this has to do with the scrawny ass power supplies and filter caps that Crown uses. What Crown amps have you used & had this experience with? What other similarly rated amps would you be referencing? Could it be the cabling used? Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted June 10, 2007 CMS Author Share Posted June 10, 2007 Agedhorse: Your "bull{censored}" response above tells me that you've never actually measured the operating voltages of an amp that is being driven hard under actual operating conditions. If you had, you would know that my statements are not "bull{censored}". Doing so might provide you with better insight as to why certain amps clip harder, more frequently, suffer from reduced dynamic headroom, lack speedy recovery once driven into saturation, don't "double down" as impedance is halved and sound "different" when trying to drive various reactive loads. Not all amps are equally well designed, load stable or linear in amplitude frequency response. Changing the load that the amp sees can alter a multitude of electrical performance criteria to a very measurable extent. When i presented hard data pertaining to a specific Crown amp that i was having problems with in regards to clipping, nobody from Crown wanted to touch the subject when posted on their forums. Doing so would have acknowledged that such a problem could exist with one of their products, let alone what might have been a good portion of their product line. Sean> The fact that Andy designs amps would lead me to think that he's measured his fair share of rail voltage under various operating conditions. What exactly is the threshold for "scrawny-ass"? Regarding clipping at the amp, it would be more prudent to investigate gain structure and specifically the input level before assuming the problem is simply that it's a Crown amp. Link to comment Share on other sites More sharing options...
Members Danny (NS::U) Posted June 11, 2007 Members Share Posted June 11, 2007 I have to call this one out - Agedhorse NOT having measured amps running in real world (or simulations real enough to be equivalent) conditions? I can't agree. Agedhorse has probably seen more power measurements, phase traces, capacitance ratings, and anything else we might care to specify than most of the rest of us put together. I'll also say that I've been in more than one situation where I thought my equipment was failing me, only to later realize that it was my own dumb self. Maybe you just ran into a few bad units, or there was some operator error? Link to comment Share on other sites More sharing options...
Members Gregidon Posted June 11, 2007 Members Share Posted June 11, 2007 Lol, I always find it funny when various people on this board tell Andy that he doesn't know what he's doing :-P I mean, granted he's definitely not infailable, but over and over he's proven (at least to me) that he knows what he is doing. Heck he designed the amp i use, and it performs better than any other bass amp i've ever used :-D Anyway, carry on..... Link to comment Share on other sites More sharing options...
Members agedhorse Posted June 11, 2007 Members Share Posted June 11, 2007 When i presented hard data pertaining to a specific Crown amp that i was having problems with in regards to clipping, nobody from Crown wanted to touch the subject when posted on their forums. Doing so would have acknowledged that such a problem could exist with one of their products, let alone what might have been a good portion of their product line. Sean Sean... I think if you look at your approach, combined with your lack of understanding about the scientific (real) details, you will discover exactly why Crown engineers didn't want to touch your comments. I'll betthey did have a good laugh in the lunch room though. You have consistently come up with bull{censored} arguments, descriptions, and technical answers on this forum. Then, when presented with a real engineering analusis you dismiss it because we "don't understand". Bull{censored}... we all know who doesn't understand. Link to comment Share on other sites More sharing options...
Members Al Poulin Posted June 11, 2007 Members Share Posted June 11, 2007 Link to comment Share on other sites More sharing options...
Members dboomer Posted June 12, 2007 Members Share Posted June 12, 2007 What exactly is the threshold for "scrawny-ass"? Have you ever seen the insides of one of these? There's not much there compared to other amps. I've measured one ... it's not like the Crown's of old at all. Link to comment Share on other sites More sharing options...
Members agedhorse Posted June 12, 2007 Members Share Posted June 12, 2007 Have you ever seen the insides of one of these? There's not much there compared to other amps.I've measured one ... it's not like the Crown's of old at all. There's not much inside other manufacturer's class D amps (including yours) either but many have no problem delivering the goods. There's more than one way to skin a cat. The only exception for Crown was the CE series... they sure missed it on the 1000/2000. Measure with a dynamic signal and I think they hold up very well. The days of continuous output ratings on the really high powered amps are over... there's no need since there is plenty of headroom. Powersoft and Lab Gruupen have done a good job at delivering the goods while not worrying about 10kW at 20kHz. Link to comment Share on other sites More sharing options...
Members Zeromus-X Posted June 12, 2007 Members Share Posted June 12, 2007 It can't have a whole lot in it, the damn thing weighs 16 pounds. I was expecting it to be made out of plastic when I saw that. Link to comment Share on other sites More sharing options...
Members aw_dee_o Posted June 13, 2007 Members Share Posted June 13, 2007 Should i bother trying to contribute another post to this thread? The last one that i did, complete with specifics as to what Crown's i was talking about, somehow "mysteriously" disappeared. Needless to say, i don't like taking the time to type out a meaningful reply only to have it censored or deleted. Sean Link to comment Share on other sites More sharing options...
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