PA Amplifiers - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
 5Likes
  • 2 Post By qirex
  • 1 Post By GIEGAR
  • 1 Post By peniku8
  • 1 Post By Glimmie
 
Thread Tools
post #1 of 24 Old 06-30-2019, 07:00 PM - Thread Starter
Advanced Member
 
mantaraydesign's Avatar
 
Join Date: Jun 2009
Posts: 940
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 272 Post(s)
Liked: 45
PA Amplifiers

Have some questions about PA amplifiers. I am looking for a 2 channel amp. I was looking at this amp at:




https://www.sweetwater.com/store/det...ower-amplifier






The description is showing Watts/Side @ 4 ohms: 3000W. That can't be true is it? Do you know the true RMS power at 4ohms?



I am looking for a 2 channel amp with true RMS power rating at 4 ohms: 500W
mantaraydesign is offline  
Sponsored Links
Advertisement
 
post #2 of 24 Old 06-30-2019, 11:56 PM
Senior Member
 
qirex's Avatar
 
Join Date: Aug 2004
Location: San Francisco
Posts: 484
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 134 Post(s)
Liked: 106
A lot of people use pro amps especially as subwoofer amplifiers, I'd guess the 3000W is at a THD level that's not quite acceptable for home critical listening and the fans are probably louder than one would want in a home environment unless they were in a closet. Behringer is among the cheapest, maybe look at Crown and QSC as well, they're generally regarded as higher quality. There's a thread in the Amp and Receiver forum about the NX line, maybe ask there for more info.
mantaraydesign and vzphoneman like this.
qirex is offline  
post #3 of 24 Old 07-01-2019, 12:49 PM
AVS Forum Special Member
 
GIEGAR's Avatar
 
Join Date: Jan 2013
Location: Australia
Posts: 2,370
Mentioned: 38 Post(s)
Tagged: 1 Thread(s)
Quoted: 992 Post(s)
Liked: 1682
Quote:
Originally Posted by mantaraydesign View Post
The description is showing Watts/Side @ 4 ohms: 3000W. That can't be true is it? Do you know the true RMS power at 4ohms?
Behringer's specs are known to be somewhat inventive. I suspect the 3000W claim may be a short-term or "burst" power figure &/or at an elevated distortion level.

Quote:
Originally Posted by mantaraydesign View Post
I am looking for a 2 channel amp with true RMS power rating at 4 ohms: 500W
In the pro amp segment, Crown's XLS DriveCore 2 series are a popular choice amongst the home theatre and DIY crowd. This is mainly due to their various consumer friendly features: single ended/RCA and balanced/XLR inputs, selectable input sensitivity, very quiet fan (if activated), cool running Class D, remote trigger, sleep mode shutdown, defeatable indicator lights etc.

The XLS DriveCore 1502 is rated at 525W into 4Ω: https://www.sweetwater.com/store/det...ower-amplifier.
mantaraydesign likes this.

Last edited by GIEGAR; 07-01-2019 at 01:05 PM.
GIEGAR is offline  
Sponsored Links
Advertisement
 
post #4 of 24 Old 07-01-2019, 01:17 PM - Thread Starter
Advanced Member
 
mantaraydesign's Avatar
 
Join Date: Jun 2009
Posts: 940
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 272 Post(s)
Liked: 45
Is there really any quality in performance regarding Class D amps versus Class AB amps?


I like the fact Class D is mush lighter in comparison to Class AB amps.



The amp I am looking for will power these speakers. Specs are below:


Input Connectors:2 Pairs Gold Plated 5 way Binding Posts


Tweeter:1" Soft Dome with Ferro Fluid


Woofers: Dual 15" Cast Frame High-Excursion Woofers


Impedance:6 ohms* (*8 ohm compatible)


Sensitivity:95.3 dB (@ 8 ohms @ 1 meter full)


Frequency Response:38 Hz - 20 kHz (-3 dB) 36 Hz - 20 kHz (-10 dB)


Power Handling:500-watts (Peak)
mantaraydesign is offline  
post #5 of 24 Old 07-01-2019, 02:08 PM
 
emcdade's Avatar
 
Join Date: Jan 2012
Posts: 1,051
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 845 Post(s)
Liked: 428
Quote:
Originally Posted by mantaraydesign View Post
Is there really any quality in performance regarding Class D amps versus Class AB amps?


I like the fact Class D is mush lighter in comparison to Class AB amps.



The amp I am looking for will power these speakers. Specs are below:


Input Connectors:2 Pairs Gold Plated 5 way Binding Posts


Tweeter:1" Soft Dome with Ferro Fluid


Woofers: Dual 15" Cast Frame High-Excursion Woofers


Impedance:6 ohms* (*8 ohm compatible)


Sensitivity:95.3 dB (@ 8 ohms @ 1 meter full)


Frequency Response:38 Hz - 20 kHz (-3 dB) 36 Hz - 20 kHz (-10 dB)


Power Handling:500-watts (Peak)
Yes, Class D typically sounds worse.
emcdade is offline  
post #6 of 24 Old 07-01-2019, 02:34 PM
Advanced Member
 
peniku8's Avatar
 
Join Date: Dec 2018
Location: Germany
Posts: 525
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 265 Post(s)
Liked: 265
Quote:
Originally Posted by qirex View Post
I'd guess the 3000W is at a THD level that's not quite acceptable for home critical listening
That would mean the amp was driven into clipping. An amp's THD is usually the lowest just before clipping.
Here are all related numbers from @notnyt 's NU6000 (same amp) testing on a non-reactive load:

https://www.avsforum.com/forum/155-d...l#post33029961

https://www.avsforum.com/forum/155-d...l#post33179737
https://www.avsforum.com/forum/155-d...l#post34661257
https://www.avsforum.com/forum/155-d...l#post34689329

https://www.avsforum.com/forum/155-d...l#post34711465


Power numbers on pro amps are short term bursts measured with a test frequency of 1khz. Capabilities vary, I've seen ratings ranging from 20ms to 150ms, which is usually enough to supply enough power for a kick drum hit (a typical kick drum's fundamental is around 63Hz, which is about 16ms. only the first cycle will be at full power, so an amp rated 1KW for 20ms will likely come close to that power rating during a full power kick drum playback).
And seriously, who does 'critical listening' at 3KW


Quote:
Originally Posted by mantaraydesign View Post
Power Handling:500-watts (Peak)
500W peak means 125W RMS. Which is kinda low for a dual 15" speaker, 500W RMS sounds more realistic for that.
Since the sensitivity is 95db/w/m, noise floor in the amp won't really be an issue. And btw, that amp will very likely be capable of burning the speakers to death when run crazy.


Quote:
Originally Posted by emcdade View Post
Yes, Class D typically sounds worse.
No

A Star Is Born - Lady Gaga goes Rock Audio&Video by Ocean Studios (me)
SKHorn Build
Samsung KS7500 - Marantz NR1504 - Klipsch R-26F - Klipsch R-25C - Klipsch R-15M - SKHorn (on FP-13000 clone)
Bass EQ for Filtered Video Games
peniku8 is offline  
post #7 of 24 Old 07-01-2019, 03:11 PM
AVS Forum Special Member
 
alan0354's Avatar
 
Join Date: Oct 2013
Location: Silicon Valley
Posts: 2,257
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1618 Post(s)
Liked: 419
By design Class AB is superior than Class D no matter what. Class D take the signal, convert to RF ( PWM or whatever), then later convert back to audio to gain the efficiency. So it has two extra steps. It is analogous to FM radio that convert audio to RF, then receiver convert the RF back to analog signal. You will NEVER get as good sound quality from FM radio as direct sound from CD, streaming etc.



That said, what do you expect from less than $500? You get a 500W class AB, it's going to be heavier, more expensive. So it's up to you. I don't know Crown and others, I don't know PA amps period, so I cannot comment on any of those.



As for 3000W, that's a lot of power!!! Most of the amps, even very expensive amp except pure class A amps can really sustain very short period of time at full power. I won't even try to challenge and try to really put in a steady signal close to 3000W. Hell, I won't even try it at 1000W. To put it in perspective, I once tried to break in a guitar speaker with 100Hz at about 25 to 30W with a Marshall guitar amp, the amp lasted about 10 minutes before the tube blew. I was using about 1/2 the rated power!!! That's a top brand very expensive amp with huge transformers and all. Lasted 10 minutes!!!

Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
alan0354 is offline  
post #8 of 24 Old 07-01-2019, 03:17 PM - Thread Starter
Advanced Member
 
mantaraydesign's Avatar
 
Join Date: Jun 2009
Posts: 940
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 272 Post(s)
Liked: 45
Quote:
Originally Posted by peniku8 View Post
That would mean the amp was driven into clipping. An amp's THD is usually the lowest just before clipping.
Here are all related numbers from @notnyt 's NU6000 (same amp) testing on a non-reactive load:

https://www.avsforum.com/forum/155-d...l#post33029961

https://www.avsforum.com/forum/155-d...l#post33179737
https://www.avsforum.com/forum/155-d...l#post34661257
https://www.avsforum.com/forum/155-d...l#post34689329

https://www.avsforum.com/forum/155-d...l#post34711465


Power numbers on pro amps are short term bursts measured with a test frequency of 1khz. Capabilities vary, I've seen ratings ranging from 20ms to 150ms, which is usually enough to supply enough power for a kick drum hit (a typical kick drum's fundamental is around 63Hz, which is about 16ms. only the first cycle will be at full power, so an amp rated 1KW for 20ms will likely come close to that power rating during a full power kick drum playback).
And seriously, who does 'critical listening' at 3KW




500W peak means 125W RMS. Which is kinda low for a dual 15" speaker, 500W RMS sounds more realistic for that.
Since the sensitivity is 95db/w/m, noise floor in the amp won't really be an issue. And btw, that amp will very likely be capable of burning the speakers to death when run crazy.




No



What amp do you recommend from www.sweetwater.com?
mantaraydesign is offline  
post #9 of 24 Old 07-01-2019, 04:28 PM
Advanced Member
 
peniku8's Avatar
 
Join Date: Dec 2018
Location: Germany
Posts: 525
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 265 Post(s)
Liked: 265
Quote:
Originally Posted by alan0354 View Post
By design Class AB is superior than Class D no matter what.

Yes, but the switching frequency is typically around 400khz and higher. Can a human detect that noise? No. So can a human hear a difference? Exactly, no.
Countless DBT's have been done on this topic and they all concluded that none of the testers could tell the amps apart (while the amps were driven within their limits ofc, and unless you have a tube amp which colours the sound).

Quote:
Originally Posted by alan0354 View Post
As for 3000W, that's a lot of power!!! Most of the amps, even very expensive amp except pure class A amps can really sustain very short period of time at full power. I won't even try to challenge and try to really put in a steady signal close to 3000W. Hell, I won't even try it at 1000W. To put it in perspective, I once tried to break in a guitar speaker with 100Hz at about 25 to 30W with a Marshall guitar amp, the amp lasted about 10 minutes before the tube blew. I was using about 1/2 the rated power!!! That's a top brand very expensive amp with huge transformers and all. Lasted 10 minutes!!!

Quality PA amps will burst their rated numbers and then drop to a lower power which it will be able to sustain infinitely (usually PSU limited).
The Speakerpower SP2-8000 will peak its rated 8000W at 100Hz and sustain 6500W.
lab.gruppen's FP-14000 will peak 14KW and sustain 4KW.

The higher end PA amps have a breaker setting so it won't trip the breaker you specified. For example, if you specify a 16A breaker on a 230V circuit, the amp will not draw more than 3.6KW for an extended period of time (usually found in units north of 5k$).
PA amps go up to like 40KW per unit, at least I have not seen (rack) amps with more power yet.
Comaring a tube guitar amp to a SMPS PA amp does not make much sense, it does the same thing but works very differently.


Quote:
Originally Posted by mantaraydesign View Post
What amp do you recommend from www.sweetwater.com?


Why not just try the Behringer you discovered? See if you like it and then swap out the fans for quieter ones. If you don't like it just return it (if that's possible in that shop?). My only concern with that amp would be the noise floor. If you notice a hiss coming from your speakers which you find unbearable, then only a very expensive PA amp will meet your desires. I haven't tried (any) Behringer amps yet, but at 95db/W/m it should be fine and just noticable when you put your ear close to the speaker.

A Star Is Born - Lady Gaga goes Rock Audio&Video by Ocean Studios (me)
SKHorn Build
Samsung KS7500 - Marantz NR1504 - Klipsch R-26F - Klipsch R-25C - Klipsch R-15M - SKHorn (on FP-13000 clone)
Bass EQ for Filtered Video Games
peniku8 is offline  
post #10 of 24 Old 07-01-2019, 04:41 PM
AVS Forum Special Member
 
alan0354's Avatar
 
Join Date: Oct 2013
Location: Silicon Valley
Posts: 2,257
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1618 Post(s)
Liked: 419
Quote:
Originally Posted by peniku8 View Post
Yes, but the switching frequency is typically around 400khz and higher. Can a human detect that noise? No. So can a human hear a difference? Exactly, no.
Countless DBT's have been done on this topic and they all concluded that none of the testers could tell the amps apart (while the amps were driven within their limits ofc, and unless you have a tube amp which colours the sound).


It's all relative, For about $1K or even to $1.5K power amp, I would think class D should be every bit as good if not better. But for high end, still the more direct path, the better. That's class AB or class A. They have class H that should be definitely better than class D. They use two class D amps for the power supplies that goes up and down with the signal, then in the middle, there's a small class A amp. But that's going to start at much higher price.

Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
alan0354 is offline  
post #11 of 24 Old 07-01-2019, 04:55 PM
Advanced Member
 
peniku8's Avatar
 
Join Date: Dec 2018
Location: Germany
Posts: 525
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 265 Post(s)
Liked: 265
Quote:
Originally Posted by alan0354 View Post
It's all relative, For about $1K or even to $1.5K power amp, I would think class D should be every bit as good if not better. But for high end, still the more direct path, the better. That's class AB or class A. They have class H that should be definitely better than class D. They use two class D amps for the power supplies that goes up and down with the signal, then in the middle, there's a small class A amp. But that's going to start at much higher price.
Quote:
In theory, there is no difference between theory and practice. But, in practice, there is.

I don't doubt what you say, in fact, I'm all the same about the digital signal path. Imo, the longer it stays digital, the better, it just satisfies me, even if I probably won't be able to hear a difference at all.
I will soon build a pair of high end speakers using high qualit parts (Jim Holtz's Bordeaux) and will test many different amps with them, to see if I can hear any difference. I own like 20 amps ranging from 100$ up to 6000$, being between 40 years and 2 years old, so that should give me quite some input (I just don't own a tube amp, just a tube preamp).
I've seen 50$ 20W amps being mistaken for 2000$ hifi amps, in a ABX scenario, so I don't think that there will be any difference. Maybe a little colouration from the very old amps (Yamaha CR-1000 etc).

A Star Is Born - Lady Gaga goes Rock Audio&Video by Ocean Studios (me)
SKHorn Build
Samsung KS7500 - Marantz NR1504 - Klipsch R-26F - Klipsch R-25C - Klipsch R-15M - SKHorn (on FP-13000 clone)
Bass EQ for Filtered Video Games
peniku8 is offline  
post #12 of 24 Old 07-01-2019, 05:22 PM - Thread Starter
Advanced Member
 
mantaraydesign's Avatar
 
Join Date: Jun 2009
Posts: 940
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 272 Post(s)
Liked: 45
Currently, I have a receiver Denon AVR-X7200WA. It's rated at 150 watts continuous at 8 ohms. Would this receiver be powerful enough to run a pair of those speakers without damaging the speakers?

Last edited by mantaraydesign; 07-01-2019 at 05:28 PM.
mantaraydesign is offline  
post #13 of 24 Old 07-01-2019, 06:16 PM
AVS Forum Special Member
 
alan0354's Avatar
 
Join Date: Oct 2013
Location: Silicon Valley
Posts: 2,257
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1618 Post(s)
Liked: 419
Quote:
Originally Posted by peniku8 View Post

I don't doubt what you say, in fact, I'm all the same about the digital signal path. Imo, the longer it stays digital, the better, it just satisfies me, even if I probably won't be able to hear a difference at all.
I will soon build a pair of high end speakers using high qualit parts (Jim Holtz's Bordeaux) and will test many different amps with them, to see if I can hear any difference. I own like 20 amps ranging from 100$ up to 6000$, being between 40 years and 2 years old, so that should give me quite some input (I just don't own a tube amp, just a tube preamp).
I've seen 50$ 20W amps being mistaken for 2000$ hifi amps, in a ABX scenario, so I don't think that there will be any difference. Maybe a little colouration from the very old amps (Yamaha CR-1000 etc).
Too bad you are in Germany, I design amps, I so wish I can get together with people that are into this particular people design speakers. I don't know Chit about designing speakers!!!

Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
alan0354 is offline  
post #14 of 24 Old 07-01-2019, 07:11 PM
Advanced Member
 
peniku8's Avatar
 
Join Date: Dec 2018
Location: Germany
Posts: 525
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 265 Post(s)
Liked: 265
Quote:
Originally Posted by mantaraydesign View Post
Would this receiver be powerful enough to run a pair of those speakers without damaging the speakers?

That statement doesn't make any sense. Destroying a speaker without exceeding its rated RMS power would require either
a) a waveform that doesn't allow for constant VC cooling such as a 40Hz square wave
b) a frequency so low that the speaker goes past Xdamage (ULF blocking caps are used to prevent this from happening)
c) very wierd stuff going on in the speaker's crossover

And all scenarios are really unrealistic.

So go for it. Try it out and see if it gets loud enough. Stop when it starts sounding bad (distorting). The amp might have protection circuits and listening to a distorted signal is unpleasant anyways, but you don't have to risk it, do you? You AVR will power your Cerwin Vega XLS-215 just fine, unless you're not using a subwoofer. The AVR will get into trouble trying to keep up with the bass (which requires the most power). If you don't have a sub, getting a sub will definitely be the more reasonable choice over getting a different amp for the tops.




Quote:
Originally Posted by alan0354 View Post
Too bad you are in Germany, I design amps, I so wish I can get together with people that are into this particular people design speakers. I don't know Chit about designing speakers!!!

That sounds very interesting, what kind of amps do you design? Guitar amps or HiFi amps? I haven't done much in that regard yet, except building a small radio, but I know my way around circuitry and physics, which certainly helps with understanding. Speaker design is something fantastic. Especially when you're looking for speakers on the market, then realize that there isn't really anything that fits your needs so you design the speaker yourself!
mantaraydesign likes this.

A Star Is Born - Lady Gaga goes Rock Audio&Video by Ocean Studios (me)
SKHorn Build
Samsung KS7500 - Marantz NR1504 - Klipsch R-26F - Klipsch R-25C - Klipsch R-15M - SKHorn (on FP-13000 clone)
Bass EQ for Filtered Video Games
peniku8 is offline  
post #15 of 24 Old 07-02-2019, 01:32 AM
AVS Forum Special Member
 
alan0354's Avatar
 
Join Date: Oct 2013
Location: Silicon Valley
Posts: 2,257
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1618 Post(s)
Liked: 419
Quote:
Originally Posted by peniku8 View Post

That sounds very interesting, what kind of amps do you design? Guitar amps or HiFi amps? I haven't done much in that regard yet, except building a small radio, but I know my way around circuitry and physics, which certainly helps with understanding. Speaker design is something fantastic. Especially when you're looking for speakers on the market, then realize that there isn't really anything that fits your needs so you design the speaker yourself!
I design both, In the 70s, I was still in the band as a guitarist, always want a good amp and I started modifying my Fender Twin Reverb into a channel switching high gain amp and even with power scaling. I got so into electronics I quit music and had a full career as electronic engineer and manager of engineering ( nothing to do with audio though). After I retired, I picked up designing guitar amps and built two of them, both channel switching, high gain with power scaling. But I don't play and not interested in playing anymore, they were a waste and just sitting in the shed after playing for a few days. So I moved to design hifi power amps like 3 years ago. I use my system to watch tv and sound is very important for me, so I can put my amps into good use, using it a few hours a day. Attached are two pictures, first picture is my 3 amps, I use the same chassis and drill the front panel the same way. Nobody except me know which one is which. This make it easy for testing as I don't have to do DBT, I just call them amp1, amp2 and amp3 for people to listen, they can see which amp I switch to and they still have no idea which one is which to judge. They are all low power amp but they can drive low impedance load down to 2ohm or less. It's designed for 4ohm speakers like my JM Lab. It's 110W for 4ohm or 220W for 2ohm. But for 8ohm, it's only 55W. The second picture is the internal of the amp, it' a dual mono block each side has it's own big transform for the output section and small transformer for the front end of the power amp. They are all integrated amp with passive preamp ( just the switching relays and a volume pot).

Too bad you literally half a world away, I don't know speakers, all I know is to spend money buying them. My current speakers are JM Lab Spectral 913.1, I just have a feeling my amps outclassed the speakers and I have to spend money to buy a better pair. That's the only item I spend money, I design my own power amp and speaker cables, so I save money on those. Even though I build my own amps, they are not exactly cheap, the parts alone cost about $900USD each. It has 9 pair of output transistors. I am thinking about a used JM Lab Diva Utopia. That should be plenty good for testing amps.



It would be so nice you design speakers and we can test things together.
Attached Thumbnails
Click image for larger version

Name:	My 3 amps.JPG
Views:	19
Size:	127.9 KB
ID:	2586688   Click image for larger version

Name:	Dual monoblock.JPG
Views:	17
Size:	150.1 KB
ID:	2586690  

Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.

Last edited by alan0354; 07-02-2019 at 02:09 AM.
alan0354 is offline  
post #16 of 24 Old 07-02-2019, 11:21 AM
AVS Forum Special Member
 
bluewizard's Avatar
 
Join Date: Jul 2008
Posts: 4,738
Mentioned: 38 Post(s)
Tagged: 0 Thread(s)
Quoted: 2317 Post(s)
Liked: 1528
Is there any particular reason why you need 1600w @ 8 ohms? That is MASSIVE POWER.

I would be inclined to recommend a low powered but higher quality Crown Amp XLS-Series -

https://www.sweetwater.com/store/search.php?s=Crown+XLS

The Crown XLS-1502 is 300w/ch - $389 -

https://www.sweetwater.com/store/det...ower-amplifier

Even that is a lot of power.

How is this system being used? Auditorium? Bar/Pub? Home System? That could matter, but regardless 300w/ch is lot of power except in true PA situations.


The Crown XLS also have Bass Management built in. For example, if you were going to use this with a Subwoofer, you could use a High-Pass to limit bass to the Front Speakers. Or if you wanted to drive a passive Sub, you could use a Low-Pass and limit the Sub to just low bass frequencies.

The XLR 1502 amp can also be Bridged to put out 1050w Mono.

Note the XLS-Series also have standard Speaker Terminals and RCA Inputs, but if needed they also have Speak-On and XLR connections.

Steve/bluewizard

Last edited by bluewizard; 07-02-2019 at 11:25 AM.
bluewizard is offline  
post #17 of 24 Old 07-02-2019, 02:11 PM
AVS Forum Special Member
 
Glimmie's Avatar
 
Join Date: Sep 2000
Location: Los Angeles, CA
Posts: 9,155
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 1074 Post(s)
Liked: 988
One thing to keep in mind. No amplifier can output more power than it takes in!

A 15a 120v circuit can supply 1800 watts.

A 20a 120v circuit can supply 2400 watts.

So unless you have a 30a 120v or run it on 240v supply, no amp is going to be able to produce 3000 watts continuously. Depending on the power supply reserve you may be able to get occasional peaks to that level. And you can also overload a circuit breaker for a few seconds and it won't trip.

Then there is the efficiency factor.

Class AB is 50-60%. Class D can reach 90%, perhaps a bit better.

So factor that in as well.
alan0354 likes this.
Glimmie is offline  
post #18 of 24 Old 07-02-2019, 02:26 PM
Senior Member
 
plasma_fan's Avatar
 
Join Date: Jan 2012
Posts: 214
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 82 Post(s)
Liked: 104
I have tried both the Behringer (inuke, but I think the same internals as the NX) and Crown XLS 1502 on my mains. The Behringer had a loud hiss in the tweeter, EASILY heard from 10 feet back, id say it was a very bad ground loop but it was a fully balanced connection. The Crown was fine, it wont impress any hifi guys, but it will work and work well.
plasma_fan is offline  
post #19 of 24 Old 07-02-2019, 02:47 PM
Senior Member
 
plasma_fan's Avatar
 
Join Date: Jan 2012
Posts: 214
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 82 Post(s)
Liked: 104
Quote:
Originally Posted by alan0354 View Post
By design Class AB is superior than Class D no matter what. Class D take the signal, convert to RF ( PWM or whatever), then later convert back to audio to gain the efficiency. So it has two extra steps. It is analogous to FM radio that convert audio to RF, then receiver convert the RF back to analog signal. You will NEVER get as good sound quality from FM radio as direct sound from CD, streaming etc.



That said, what do you expect from less than $500? You get a 500W class AB, it's going to be heavier, more expensive. So it's up to you. I don't know Crown and others, I don't know PA amps period, so I cannot comment on any of those.



As for 3000W, that's a lot of power!!! Most of the amps, even very expensive amp except pure class A amps can really sustain very short period of time at full power. I won't even try to challenge and try to really put in a steady signal close to 3000W. Hell, I won't even try it at 1000W. To put it in perspective, I once tried to break in a guitar speaker with 100Hz at about 25 to 30W with a Marshall guitar amp, the amp lasted about 10 minutes before the tube blew. I was using about 1/2 the rated power!!! That's a top brand very expensive amp with huge transformers and all. Lasted 10 minutes!!!
Serious question, what is your take on the Hypex NCore modules? I appreciate that you design your own amps and as such have your bias and favorites. However the Hypex is Class D amp with some serious chops, lowest distortion of anything I am aware of. https://www.hypex.nl/img/upload/doc/...Technology.pdf They also get top reviews from the magazines (when installed in expensive branded amps) https://www.stereophile.com/content/...ower-amplifier
The designer also believes in supporting the DIY community and offers the NC400 modules at a very reasonable cost.
plasma_fan is offline  
post #20 of 24 Old 07-02-2019, 03:18 PM
Advanced Member
 
peniku8's Avatar
 
Join Date: Dec 2018
Location: Germany
Posts: 525
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 265 Post(s)
Liked: 265
Quote:
Originally Posted by alan0354 View Post
I design both, In the 70s, I was still in the band as a guitarist, always want a good amp and I started modifying my Fender Twin Reverb into a channel switching high gain amp and even with power scaling. I got so into electronics I quit music and had a full career as electronic engineer and manager of engineering ( nothing to do with audio though). After I retired, I picked up designing guitar amps and built two of them, both channel switching, high gain with power scaling. But I don't play and not interested in playing anymore, they were a waste and just sitting in the shed after playing for a few days. So I moved to design hifi power amps like 3 years ago. I use my system to watch tv and sound is very important for me, so I can put my amps into good use, using it a few hours a day. Attached are two pictures, first picture is my 3 amps, I use the same chassis and drill the front panel the same way. Nobody except me know which one is which. This make it easy for testing as I don't have to do DBT, I just call them amp1, amp2 and amp3 for people to listen, they can see which amp I switch to and they still have no idea which one is which to judge. They are all low power amp but they can drive low impedance load down to 2ohm or less. It's designed for 4ohm speakers like my JM Lab. It's 110W for 4ohm or 220W for 2ohm. But for 8ohm, it's only 55W. The second picture is the internal of the amp, it' a dual mono block each side has it's own big transform for the output section and small transformer for the front end of the power amp. They are all integrated amp with passive preamp ( just the switching relays and a volume pot).

Too bad you literally half a world away, I don't know speakers, all I know is to spend money buying them. My current speakers are JM Lab Spectral 913.1, I just have a feeling my amps outclassed the speakers and I have to spend money to buy a better pair. That's the only item I spend money, I design my own power amp and speaker cables, so I save money on those. Even though I build my own amps, they are not exactly cheap, the parts alone cost about $900USD each. It has 9 pair of output transistors. I am thinking about a used JM Lab Diva Utopia. That should be plenty good for testing amps.

It would be so nice you design speakers and we can test things together.

Love the looks of brushed metal front plates! My SPL Goldmike also has a brushed light-brass-coloured front plate which looks just so good.
Wish I could give these speakers a listen. I was initially thinking about buying a pair of Focal (JM Labs now) speakers for the studio, but went with Genelec instead. Can't wait to get the Bordeaux project going (will build 3 pairs). Just the parts are over 1 grand per speaker and those who have built it say that it's the best speaker they've ever heard.
Also been making my own speaker cables forever, especially since I need (have) hundreds of meters of speaker cable for PA. A 15m 4x4mm² (about 11AWG) is 125USD. Copper is crazy expensive!

A Star Is Born - Lady Gaga goes Rock Audio&Video by Ocean Studios (me)
SKHorn Build
Samsung KS7500 - Marantz NR1504 - Klipsch R-26F - Klipsch R-25C - Klipsch R-15M - SKHorn (on FP-13000 clone)
Bass EQ for Filtered Video Games
peniku8 is offline  
post #21 of 24 Old 07-02-2019, 04:07 PM
AVS Forum Special Member
 
alan0354's Avatar
 
Join Date: Oct 2013
Location: Silicon Valley
Posts: 2,257
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1618 Post(s)
Liked: 419
Quote:
Originally Posted by plasma_fan View Post
Serious question, what is your take on the Hypex NCore modules? I appreciate that you design your own amps and as such have your bias and favorites. However the Hypex is Class D amp with some serious chops, lowest distortion of anything I am aware of. https://www.hypex.nl/img/upload/doc/...Technology.pdf They also get top reviews from the magazines (when installed in expensive branded amps) https://www.stereophile.com/content/...ower-amplifier
The designer also believes in supporting the DIY community and offers the NC400 modules at a very reasonable cost.
I have no comment on this particular amp as I never heard it before. All I can say is in general that Class D involves up convert audio signal to RF and convert back to audio signal. It has to go through two extra conversion than a simple class A or class AB. Maybe this one has some secret juice. The ultimate is listening.

Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.

Last edited by alan0354; 07-02-2019 at 04:48 PM.
alan0354 is offline  
post #22 of 24 Old 07-02-2019, 07:46 PM
AVS Forum Special Member
 
alan0354's Avatar
 
Join Date: Oct 2013
Location: Silicon Valley
Posts: 2,257
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1618 Post(s)
Liked: 419
Quote:
Originally Posted by peniku8 View Post
Love the looks of brushed metal front plates! My SPL Goldmike also has a brushed light-brass-coloured front plate which looks just so good.
Wish I could give these speakers a listen. I was initially thinking about buying a pair of Focal (JM Labs now) speakers for the studio, but went with Genelec instead. Can't wait to get the Bordeaux project going (will build 3 pairs). Just the parts are over 1 grand per speaker and those who have built it say that it's the best speaker they've ever heard.
Also been making my own speaker cables forever, especially since I need (have) hundreds of meters of speaker cable for PA. A 15m 4x4mm² (about 11AWG) is 125USD. Copper is crazy expensive!
You think those speaker kits can match JM Lab Utopia?

Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
alan0354 is offline  
post #23 of 24 Old 07-02-2019, 08:06 PM
Advanced Member
 
peniku8's Avatar
 
Join Date: Dec 2018
Location: Germany
Posts: 525
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 265 Post(s)
Liked: 265
Quote:
Originally Posted by alan0354 View Post
You think those speaker kits can match JM Lab Utopia?

Hard to tell, but iirc somebody said that he prefered the "Statements II" over the Bowers&Wilkins 803, which are said to be great value for the money. And the Bordeaux is an upgraded version to the Statements II design. People who heard them describe it the way that the speaker vanishes on your soundstage and there is just music. Or positions where a musician would be sitting. They're said to reveal every little detail in a recording, which is very important to me as a mixing/mastering engineer (I often master records on my home setup, which I've mixed in the studio or recieved a mix from another studio to master). They should be a great addition to my flawless sub (SKHorn, extremely low distortion levels at any (sane) SPL inside, down to 18Hz).

A Star Is Born - Lady Gaga goes Rock Audio&Video by Ocean Studios (me)
SKHorn Build
Samsung KS7500 - Marantz NR1504 - Klipsch R-26F - Klipsch R-25C - Klipsch R-15M - SKHorn (on FP-13000 clone)
Bass EQ for Filtered Video Games
peniku8 is offline  
post #24 of 24 Old 07-13-2019, 05:14 PM
Member
 
Join Date: Apr 2015
Location: Silicon Valley
Posts: 65
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Liked: 18
One thing to remember is that 90% of your listening will be at levels which require less than 50 watts, even party levels will likely be less than 100 watts.

If you ever pushed 500 watts at those speakers your ears would be wasted Just a thought

Jim Meader
JimMeader is offline  
Sponsored Links
Advertisement
 
Reply 2-Channel Audio

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off