Quiet PA amps

Means you are clipping the input of the amp right.


You don't need the full power of those amplifiers in that case though do you. So instead of turning down the DSP output level for the CD's leave it at the same level as the mids and turn the HF amp gains down that amount. Yamaha has a cover that goes over the gain controls for this exact purpose I'm sure.

I have the same issue with my setup.. P3500 or P5000 driving CDs directly but so far I have just been ignoring it because once the DJ starts playing it's a non issue.

In my case, the best case scenario for noise is a gain structure where my HF amp is at around 8:30 PM from its start at 6 PM. The volume dial is almost useless. It’s fine, as I use the volume control from my PC source, but it shows how little gain is required from an amp when you use very sensitive speakers. The HF amp I am using is capable of around 1.5 clean Watts per channel.
 
I use my PA system as my home HI-FI and so have an interest in any PA amps that are close to silent ...

Hi this is a very interesting topic. I have been thinking lately to use a PA amp in my room for stereo listening. And fans can be an issue.
I am not an expert but i understand that lowering the supply voltage to the fans they spin at a lower speed ?
It this is true and considering the very low power they need why not using those little dc-dc step down converters available on the web ?

Module xl6009 cn6009 DC-DC Converter Step Up Voltage Adjustable Lift | eBay

You can set the Vout until the fan is not hear from the listening position but still spinning enough
Only issue could arise if the amps are pushed to the limit and the fans cannot provide enough flow rate ... but in a home situation i guess that happens only during some short duration music peaks ? :rolleyes:
For me the deciding factor would be sound quality and current delivery ... i can stand a little whisper from the fans ... but i very much like clean and powerful sound.
 
I have a Nady XA-900 amp in my living room that I use for my subwoofers. Out of the box, the fans make a lot of noise. They run on 12V dc. I bought (2) adjustable regulator boards based upon the LM317 regulator off of flea-bay. I installed one in the +12v line of each fan and adjusted the voltage as low as I could with the fan still starting reliably at turn-on. Ended up being somewhere between 4.5 and 5 volts. The fans are almost silent now. I don't notice them while sitting 6-8 feet away. My listening room isn't big and I don't listen loud so this works fine. I thought about disconnecting the fans altogether, but didn't want to tempt fate.
 
Same here. I selected the smallest amplifier that has both balanced XLR inputs and high-current SpeakON outputs. I would have purchased a mono block if there were one available within reason, but settled on something stereo that could be bridged mono. I could have gone with the 1U half rack SPA2-60 bridged for 200W of convection cooled power, but I like sticking with the same input and output connectors that my other amps use in case I want to swap back.

Considering how much headroom the Pass Labs XA30.8 provides to my tiny LINN TUKAN speakers, it seemed only fair to give the sub a lot of headroom as well.

p.s. QSC support mentioned that it's actually possible to get more power out of a single channel without bridging, because the single power supply in the stereo amplifier doesn't have to feed both channels when the second channel is unused. I don't quite follow the math, since it seems like the supply should be capable of the same amount of total power either way (half+half versus all-on-one+nothing-on-two), but I'll take their word for it.

They also assured me that it would be fine to run the RMX or SPA with the second channel powered but disconnected (something I would normally be reluctant to do). I'm slightly tempted to try the RMX 850a in stereo mode with only one channel connected, but then I would have to rewire the SpeakON.
QSC were probably saying that the increase when bridged would be less than 3dB so barely noticeable. IN HiFi use the extra distortion added by bridging miggt outweigh the potentiol extra power.
 
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For those looking for ouput powers up to 800W and fanless Extron amplifiers look very good:
https://www.audiosciencereview.com/.../extron-xpa-1002-plus-amplifier-review.35557/ (great performance)
https://www.extron.com/product/xpau3502 (2*350W per channel 8/4ohm)
https://www.extron.com/product/xpa4002 (1*800W 8ohm, 2*400W 4ohm)
https://www.extron.com/product/xpau758 (8*75W in half a rack space passive!)
https://www.extron.com/Network-Power-Amplifiers/prodsubtype-635 (Dante Ethernet audio input half rack amps for very compact PC based setups)

I have a XPA 1002 that I purchased to test out so will let you know my impressions.
 
I have a XPA 1002 that I purchased to test out
How did it go?

I found a very interesting amplifier a while ago that have very "good" specs.
1691671391420.png


https://vi.aliexpress.com/item/1005005488725770.html

Have been considering getting one, though it's only 1U so suspect it might be noisy.
 
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I have extron XPA 1002 and 2* XPA 2004 they all work great! I even had the chance to run the 2004's hard at a house party with no issues. They run very cool.

the sexual noise ratio amp isn't very good value that kind of price would get a multi thousand W amp from Gisen (not excessively noisy for a PA amp) .
 
Good stuff about the Extron amps then, nice.

I am looking for amplifiers with integrated DSP though, and you can get those "sexual" amps with integrated Dante as well.
A few more notes give a lot higher numbers if that's your thing..

At any rate, although sexual noise seems like a very nice thing I am leaning more towards the LA8 for home use, it is 2U, made by Sinbosen, has DSP.
 
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LA8 looks to be a Lab gruppen dressed up as a L'acoustics with a homebrew DSP. That Dante is starting to become available on china amps is very exciting running everything over network would be cool, our DSPs (symetrix radius AEC) have Dante already. This must mean there is a cheap Dante module available. If you look on ebay there are plenty of ex-install extron amps but I don't know about newer models, I guess look up your local distributor. They also do an 8 output model with Dante input.

Attachment is my Extron rack (DSP is only temp I use 8x8 and DIGIO in this rack normally). Not bad for 8*200W.
 

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Meanwhile, QSC has these SPA2-* and SPA4-* half rack 1U amps. I should have bought one of those, but I'd already wired by sub with a SpeakON connector, and I'm too lazy to rewire for the SPA2-60 screw terminals. The SPA2-* do not have a fan, so I bet they'd be quiet. They even come with adapters for folks who need to mount them in a full-width rack.
Following up here, I finally gave up on trying to find a quiet fan for my home theater .1 channel QSC 850a.

For a replacement, I started with the SPA2-60, which was a mistake since a subwoofer really needs more than 60W. I wasn't paying attention when I ordered it. It worked fine for the sub, and I used it for quite some time, but it just didn't have enough volume. It was difficult to find stock of the SPA2-200 during COVID, but I eventually found one from Markertek. Swapping the SPA2-200 in place of the SPA2-60 was easy, given the connectors, and now I have plenty of volume for the subwoofer. I'm really glad that I went fanless, and the auto-power-off feature is nice.
 
I have extron XPA 1002 and 2* XPA 2004 they all work great!
They are pretty handy little amps! My 1002 does have that annoying ticking sound that's discussed at length on audioscience so I wouldn't use it in my main hifi rack but I'm just running it connected to a dj mixer and some monitors and it's perfectly adequate in that situation and does run cool. More power would be nice but the 60w 1002 is mostly what comes up here in Australia it seems.
 
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I have a pair of 1002 and a 4002.
No hum, no buzz, no ticking.
No fans.
Just deadly...:cool:

A minor bugbear is having manually wire the Phoenix type connectors.

A kind @kipman725 help pushed me in the right direction…
 

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The XPA 1002 seems to be a nice amplifier. It seems I could use 3 or 4 with a common mute - and what is even more useful - with a single pot common volume! I lack common volume control (and mute on power up/down) when using two Thomann DSP minis for 4 way stereo amplification. The Behringer EPQ304 with disconnected fans is OK, but produces a bit too much hiss. Are the Extrons silent enough to run compression drivers without attenuation?
 
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