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post #901 of 1763 Old 09-23-2015, 02:24 PM
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What are is the verdict on the Crown XLS 1000, 1500, 2000, 2500 that are on sale/closeout? at Amazon right now?

This question for a buddy of mine who is considering a set - @Scrappydue

https://www.avsforum.com/forum/122-gr...-closeout.html

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post #902 of 1763 Old 09-23-2015, 04:01 PM
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@Archaea
for mains, there was a report of the 2000 or higher having less noise than the lower models (perhaps only a 1000 problem).
http://www.hometheaterequipment.com/...l-thread-1319/

@mastermaybe was running them with subs (medium size sealed), quite happy iirc.


@Stereodude ran into a possible ulf glitch:
https://www.avsforum.com/forum/155-di...m-houston.html


@lukeamdman identified a minor hiccup when running some sweeps on his gjallerhorn.
https://www.avsforum.com/forum/155-di...l#post33915818


on this last point, I'm foggy, but i seem to recall something about a guy who moved from xls up to xli and thought the bass sound tighter/stronger. xli is a 43 pounder with an old school power supply and analog output stage.

the fans are quiet and almost never come on.
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post #903 of 1763 Old 09-23-2015, 04:12 PM
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LTD02,


You are a continual asset to this community. I appreciate you digging that stuff up!


Except for I see Andrew Robinson's name in that first link and closed it nearly immediately. His reviews are the very definition of subjective fluff and audiophile snake oil, and I stopped giving his expert opinion any credibility after reading this review and subsequently owning the Sherbourn 7-350. (which was a good amp, at a good value in it's $1,000 close out price --- but not magical any more than any other functional pro amp I own).
http://www.andrew-robinson-online.co...wer-amplifier/


----------------


My buddy scrappydue texted me about the crowns last night. I initially told him not interested at all because I have enough amps already ----- I have some of the X1000 amps which mtg90 noted had audible distortion to his ears, which bore out somewhat in my quick and dirty (no real clue what I'm doing) distortion testing.
Post 465
https://www.avsforum.com/forum/155-di...l#post27180026





I don't think I could tell an audible fault from my casual listening at that junction (non instant switch listening) - but IIRC those x1000 amps are just rebadged XLI800 amps (manufactured for Guitar Center and Musician's Friend stores only). Anyway, as I thought more about the price, I have a couple old school Crown XLS amps. The XLS 202 and the XLS 402 which I'm using for my mains right now on the Denon x7200wa for L/C/R. (only because I actually have to use external amps to drive my 7.1.4 speaker setup - otherwise I 'd just be using the built in 9 amplifiers)

I'm not one that thinks amps sound different (to my ears anyway) so I'm not even sure why this question is fluttering around in my head - but I'm curious what the distortion profile would be like on the new XLS 1000 or XLS 1500 as compared to the X1000 or XLS202 and XLS 402 I have?


Rhetorical question - Why the heck does Crown reuse naming schemes so confusingly? My class A/B XLS 202 and XLS 402 look nothing like the (completely different amp class and technology) newer class D XLS 1000, etc. The X1000 being a rebadged XLI 800 is weird. Muddy the waters much, Crown?






-------


guess I'll stick with my Crown XLS 202 (bridged to center) and my Crown XLS 402 (stereo for l/r) - Post 90.
https://www.avsforum.com/forum/155-di...l#post24156643

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post #904 of 1763 Old 09-23-2015, 04:36 PM
 
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Quote:
Originally Posted by LTD02 View Post
@Archaea
for mains, there was a report of the 2000 or higher having less noise than the lower models (perhaps only a 1000 problem).
http://www.hometheaterequipment.com/...l-thread-1319/

@mastermaybe was running them with subs (medium size sealed), quite happy iirc.


@Stereodude ran into a possible ulf glitch:
https://www.avsforum.com/forum/155-di...m-houston.html


@lukeamdman identified a minor hiccup when running some sweeps on his gjallerhorn.
https://www.avsforum.com/forum/155-di...l#post33915818


on this last point, I'm foggy, but i seem to recall something about a guy who moved from xls up to xli and thought the bass sound tighter/stronger. xli is a 43 pounder with an old school power supply and analog output stage.

the fans are quiet and almost never come on.
FWIW the XLS1000 has a SNR spec of > 97 dB, the 1500/2000/2500 >103 dB

I've used my XLS1500s for mains and now for subs (running sealed SI HT18D2s as a 4ohm load on each of 2ch mode currently but going back to bridged soon), no complaints, great bang for the buck IMO, even more so on the closeout pricing.
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post #905 of 1763 Old 09-23-2015, 04:39 PM
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Quote:
Originally Posted by Archaea View Post
LTD02,
Except for I see Andrew Robinson's name in that first link and closed it nearly immediately. His reviews are the very definition of subjective fluff and audiophile snake oil, and I stopped giving his expert opinion any credibility after reading this review and subsequently owning the Sherbourn 7-350. (which was a good amp, at a good value in it's $1,000 close out price --- but not magical any more than any other functional pro amp I own).
http://www.andrew-robinson-online.co...wer-amplifier/
yeah...i know what you are saying. there are some decent facts in the thread however. try to ignore the other stuff, at least to the extent that it is possible. :-) post 38 for example he explains that he spoke with a crown rep who indicated the noise floor is lower on the 2000 and up series and apparently that made quite a difference. i suppose that is in the specs, but specs can be a little tricky as s/n is often referenced off full power and doesn't precisely catch the noise floor. anyway, fwiw...

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post #906 of 1763 Old 09-23-2015, 04:50 PM
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Quote:
Originally Posted by Archaea View Post


I'm not one that thinks amps sound different (to my ears anyway) so I'm not even sure why this question is fluttering around in my head - but I'm curious what the distortion profile would be like on the new XLS 1000 or XLS 1500 as compared to the X1000 or XLS202 and XLS 402 I have?

always have to stick this little asterisk on that though. *with high sensitivity mains, a difference in noise floor can be audible. once the noise floor is down to background level, not so much. of course, background noise level can vary 15-20db or more from one environment to another, which makes it really difficult to compare one person's reports from another's.

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post #907 of 1763 Old 09-24-2015, 08:32 AM
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Quote:
Originally Posted by LTD02 View Post
@Archaea
for mains, there was a report of the 2000 or higher having less noise than the lower models (perhaps only a 1000 problem).
http://www.hometheaterequipment.com/...l-thread-1319/

@mastermaybe was running them with subs (medium size sealed), quite happy iirc.


@Stereodude ran into a possible ulf glitch:
https://www.avsforum.com/forum/155-di...m-houston.html


@lukeamdman identified a minor hiccup when running some sweeps on his gjallerhorn.
https://www.avsforum.com/forum/155-di...l#post33915818


on this last point, I'm foggy, but i seem to recall something about a guy who moved from xls up to xli and thought the bass sound tighter/stronger. xli is a 43 pounder with an old school power supply and analog output stage.

the fans are quiet and almost never come on.
Guys:

I just got this "notice" via email and haven't read everything, but...

I couldn't run the xli 3500 on my dual sealed UM18's...thing continually shut down.

I ended up grabbing a QSC 4050a.

Ansolute beast. Zero issues. Had a cpl retailers pitted against one another and got it for ~ $1350 IIRC.

I ran the xls 1500's on my channels with no issues: extreme levels for periods on occasion, no issues.

No clue it they're suitable for serious sub use.

What I know.

James
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Last edited by mastermaybe; 09-24-2015 at 08:36 AM.
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post #908 of 1763 Old 09-24-2015, 09:34 AM
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Quote:
Originally Posted by mastermaybe View Post
Guys:

I just got this "notice" via email and haven't read everything, but...

I couldn't run the xli 3500 on my dual sealed UM18's...thing continually shut down.

I ended up grabbing a QSC 4050a.

Ansolute beast. Zero issues. Had a cpl retailers pitted against one another and got it for ~ $1350 IIRC.

I ran the xls 1500's on my channels with no issues: extreme levels for periods on occasion, no issues.

No clue it they're suitable for serious sub use.

What I know.

James
Was it in bridged mode?
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post #909 of 1763 Old 10-04-2015, 02:33 PM
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Ricci has posted an amplifier comparison on data-bass. His method is quite different in that he uses real speakers as loads and acoustic output measurements.
http://data-bass.ipbhost.com/index.p...k20-dsp-aesop/
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post #910 of 1763 Old 10-05-2015, 05:56 PM
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Quote:
Originally Posted by LTD02 View Post
@Archaea
for mains, there was a report of the 2000 or higher having less noise than the lower models (perhaps only a 1000 problem).
http://www.hometheaterequipment.com/...l-thread-1319/

@mastermaybe was running them with subs (medium size sealed), quite happy iirc.


@Stereodude ran into a possible ulf glitch:
https://www.avsforum.com/forum/155-di...m-houston.html


@lukeamdman identified a minor hiccup when running some sweeps on his gjallerhorn.
https://www.avsforum.com/forum/155-di...l#post33915818


on this last point, I'm foggy, but i seem to recall something about a guy who moved from xls up to xli and thought the bass sound tighter/stronger. xli is a 43 pounder with an old school power supply and analog output stage.

the fans are quiet and almost never come on.

I was thinking about this - and you know what's funny - the Musician's Friend and Guitar center X1000 amp based on the XLI 800. (stickers inside the X1000 all say XLI 800) was the amp that MTG90 stated had some audible distortion to his ears, and my elementary testing showed it did indeed have more distortion than any of the other amps I own and tested at that time.
Post 465
https://www.avsforum.com/forum/155-di...l#post27180026


In the end this hobby involves a lot of he said she said stuff. One guy doesn't like something, compared to another product, and the next guys take is the exact opposite. It's so hard to decipher.
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(13) JBL CBT 70j-1 | Denon x7200wa | Sherbourn PA 7-350 amplifier | (8) Ultimax 18" sealed subwoofers | (4) iNuke DSP 6000 amplifiers | (4) MB Quart 12" subwoofers mounted direct mounted to Berkline theater chairs BOSS style | Epson 5040UB Projector | Jamestown 144" acoustic transparent 2.35:1 screen w/ Seymour XD fabric
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post #911 of 1763 Old 10-05-2015, 07:37 PM
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Quote:
Originally Posted by Archaea View Post
In the end this hobby involves a lot of he said she said stuff. One guy doesn't like something, compared to another product, and the next guys take is the exact opposite. It's so hard to decipher.

it really is. and then even worse is quite often one person will hear something but then make a false attribution--they truly believe what they were hearing was the result of one factor, when in fact what they were hearing was the result of a completely different factor. then throw in the placebo effect--and I mean true placebo where folks actually hear things differently based on some aspect even though the sound is the same--and it really gets confusing. then consider that, particularly the music side, this is all to create emotion within us and it really really becomes a challenge to sort it all out because what we are dealing with is by definition illogical, yet extremely important. as a result, i'm not actually sure who is happier...the guys who knows all there is to know...or the guy who knows nothing. be careful with apples... :-)
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post #912 of 1763 Old 10-05-2015, 08:46 PM
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be careful with apples... :-)
I like Granny Smith apples. I find them to be more airy with better detail.

David Gage
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"You don't listen to our subs, you EXPERIENCE them!"
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post #913 of 1763 Old 10-06-2015, 07:53 AM
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as a result, i'm not actually sure who is happier...the guys who knows all there is to know...or the guy who knows nothing. be careful with apples... :-)
I think the guy who's happiest is the one who can get to the point where they have achieved their best bang-for-the-buck. (Well, I suppose that assumes your target is the knee of the bang/buck curve.)

I just let everybody else hash it out and rank the equipment, then I buy what I can reasonably afford on that list. I suppose that puts me more in line with "the guys that knows nothing" but I'm also getting the happiness of the guy that knows everything for free. Double happy.

..dane
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post #914 of 1763 Old 10-06-2015, 07:58 AM
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the person who is happiest is the one who gets on here long enough to build something hes satisfied with and then never comes back lol
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post #915 of 1763 Old 10-06-2015, 04:22 PM
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Quote:
Originally Posted by SpeakerPower View Post
Ricci has posted an amplifier comparison on data-bass. His method is quite different in that he uses real speakers as loads and acoustic output measurements.
http://data-bass.ipbhost.com/index.p...k20-dsp-aesop/
Impressive results.

I've often wondered just how powerful of an amp could be made to fit in 4RU with no holds barred.
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post #916 of 1763 Old 02-26-2016, 12:08 PM
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Woo, measurements for Grace Digital GDI-BTAR513 done, it's awful. Lepai LP-2020A+ is worlds better, but less output. Need to put the 40db pad back on tomorrow and then measure some serious amps. My NL4FX plugs come in

0.0004% THD through a loopback. This should do well for measuring I think

Necro reply ... Just got one of these GDI-BTAR513. Not sure how to read your graph , I assume the spike is the problem. Has anyone done any recent tests on the latest batches, maybe they addressed the issues ...
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post #917 of 1763 Old 02-26-2016, 12:09 PM - Thread Starter
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Necro reply ... Just got one of these GD BTAR513. Not sure how to read your graph Has anyone done any recent tests on the latest batches, maybe they addressed the issues ...
That graph is for a 2i2, the BD BTAR stuff is trash, at least the one I had in hand. I can test it if you want, shouldn't take very long since I've done one already. The one I had, the EQ buttons were reversed, treble adjusted bass and vise versa, the amp had insane amounts of 2nd order distortion and huge phase shifts. Just cover shipping.

That said, there are much better options. I'm currently using an rpi with a bluetooth dongle as a usb audio sink hooked up to an emotiva mini-x a100. Granted, bit bigger, but there are still better options.

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That graph is for a 2i2, the BD BTAR stuff is trash, at least the one I had in hand. I can test it if you want, shouldn't take very long since I've done one already. The one I had, the EQ buttons were reversed, treble adjusted bass and vise versa, the amp had insane amounts of 2nd order distortion and huge phase shifts.
I read they had some power supply problems at some point, or is it trash because of the internals and not the power supply?
Any recommendations for a good integrated digital amp with nice features such as USB DAC, Bluetooth, etc. based on what you tested? Oh yeah, affordable too
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post #919 of 1763 Old 02-26-2016, 12:17 PM - Thread Starter
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Originally Posted by SirDracula View Post
I read they had some power supply problems at some point, or is it trash because of the internals and not the power supply?
Any recommendations for a good integrated digital amp with nice features such as USB DAC, Bluetooth, etc. based on what you tested? Oh yeah, affordable too
I don't have anything I can recommend off hand. I'm using an $8 usb dac and a $5 bt dongle on my rpi and it works great.

http://www.amazon.com/gp/product/B014ANW4VU

The 2i2 is about $150 (on sale often for $100) and is an excellent dac with balanced outputs.

As for something with everything integrated, I dunno what's good, I wasn't able to find anything easily. The btar looked like it could be good, but I was amazed at how bad it was. Like I said, if you want me to test yours let me know.
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post #920 of 1763 Old 02-26-2016, 12:17 PM
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Others I'm looking at: NAD D 3020, Denon PMA-50, TEAC AI-301DA and AI-101DA ... but all are in a different price bracket compared to the GD. Anything from the list that's worth owning? The NAD 3020?
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post #921 of 1763 Old 02-26-2016, 12:18 PM - Thread Starter
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Originally Posted by SirDracula View Post
Others I'm looking at: NAD D 3020, Denon PMA-50, TEAC AI-301DA and AI-101DA ... but all are in a different price bracket compared to the GD. Anything from the list that's worth owning? The NAD 3020?
No experience with them directly, but those are all competent manufacturers.
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post #922 of 1763 Old 03-06-2016, 04:44 PM
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@Decadent_Spectre asked me to test my cv-5000 amp down to 10hz to see if it is relatively flat down to that point. (Specs give -3dB point at 5hz on this amp - just hoping to validate)

I downloaded 0dbfs test tones from 1hz up to 120hz from http://www.wavtones.com/functiongenerator.php
AVR is a Denon x7200wa.
Multimeter is a cheapo Chinese unit.
http://www.harborfreight.com/7-funct...ter-98025.html

Ill turn off eq, play the sine wav test tones and record voltages for 40hz, 20hz, and 10hz sine waves directly from the amp's speaker output terminals.

Is my cheapo multimeter up to this simple task?
Should my amp have the subwoofer load attached or disconnected for such a test?
What setting do I use on my cheapie multimeter to check the voltage from the speaker terminals without shorting my CV-5000 amp

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post #923 of 1763 Old 03-06-2016, 05:01 PM
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Quote:
Originally Posted by Archaea View Post
@Decadent_Spectre asked me to test my cv-5000 amp down to 10hz to see if it is relatively flat down to that point. (Specs give -3dB point at 5hz on this amp - just hoping to validate)

I downloaded 0dbfs test tones from 1hz up to 120hz from http://www.wavtones.com/functiongenerator.php
AVR is a Denon x7200wa.
Multimeter is a cheapo Chinese unit.
http://www.harborfreight.com/7-funct...ter-98025.html

Ill turn off eq, play the sine wav test tones and record voltages for 40hz, 20hz, and 10hz sine waves directly from the amp's speaker output terminals.

Is my cheapo multimeter up to this simple task?
Should my amp have the subwoofer load attached or disconnected for such a test?
What setting do I use on my cheapie multimeter to check the voltage from the speaker terminals without shorting my CV-5000 amp

If you'll just be measuring the max voltage at each frequency, I wouldn't have any load connected to the amp.


Set it to the "ACV" 200 setting and use the bottom two connections on the multi meter (COM and VmA).


That multi-meter will be measuring Vpp rather than Vrms as well, so just an FYI.


EDIT: Since this will be Vpp you may need to use the ADV 750 setting instead of 200.

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post #924 of 1763 Old 03-06-2016, 05:12 PM - Thread Starter
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Originally Posted by lukeamdman View Post
If you'll just be measuring the max voltage at each frequency, I wouldn't have any load connected to the amp.


Set it to the "ACV" 200 setting and use the bottom two connections on the multi meter (COM and VmA).


That multi-meter will be measuring Vpp rather than Vrms as well, so just an FYI.


EDIT: Since this will be Vpp you may need to use the ADV 750 setting instead of 200.
most multimeters measure vrms. Most cheap ones also have trouble with low frequency signals.
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post #925 of 1763 Old 03-06-2016, 05:20 PM
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Originally Posted by notnyt View Post
most multimeters measure vrms. Most cheap ones also have trouble with low frequency signals.

My cheaper Klein MM1000 (~$65) doesn't measure Vrms.


My Fluke 117 and 115 measure Vrms but have trouble (oscillation) below 20hz.
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post #926 of 1763 Old 03-07-2016, 02:34 PM
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all multimeter except the expensive ones mesure Vrms and are only accurate around 50-60 Hz.

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post #927 of 1763 Old 03-18-2016, 12:52 PM
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So I just read through this whole thread and can't find a link to all the final results. Did all the amps mentioned get tested or did something happen and I missed it?
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post #928 of 1763 Old 03-18-2016, 03:14 PM
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Originally Posted by john lutz View Post
So I just read through this whole thread and can't find a link to all the final results. Did all the amps mentioned get tested or did something happen and I missed it?
He hasn't finished testing yet. He probably doesn't have the time.
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post #929 of 1763 Old 03-19-2016, 10:24 AM
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He hasn't finished testing yet. He probably doesn't have the time.
Certainly understandable. Pretty ambitious project...testing all those amps that folks are interested in. I was looking forward to more info on the IPR2 7500, especially anything that would indicate noise issues.
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post #930 of 1763 Old 03-19-2016, 06:45 PM
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Certainly understandable. Pretty ambitious project...testing all those amps that folks are interested in. I was looking forward to more info on the IPR2 7500, especially anything that would indicate noise issues.

not sure if this may be useful info or not:
http://data-bass.ipbhost.com/index.p...tests/?p=10302
pretty much same amp, but with a few better components as I understand it.


beastaudio and brian6751 were running 7500's. may be able to answer your question.

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