(1) I got a pair of "200 watt" Acoustic Reality amps... even driving them into the Maggies, I can't say I've ever driven them to their limits. I also have an NC252MP that I need to put together one of these days. The Acoustic Reality amps sound closed in at the top end ( output filter ) but have outstanding deep bass and midrange... lots of SLAM, lots of damping factor. I'd use still use them if my Maggies could be biamped.
That's 200 watts.
(2) I believe the gain in your amp is adjustable. Read the link I sent you.
(3) Use an SPL meter. It is possible that you are running into a frequency based issue? My class A amps all have a lot more distortion than the class A/B amps and subjectively this changes HOW I hear them. So, you need to measure how loud they are going. In addition, you might want to put in a microphone and figure out the frequency spectrum of the sound. Perhaps the Ncore amp is clean while the Plinnius starts to introduce some distortion that makes it "sound" louder?
(4) I ignore ASR.
That's 200 watts.
(2) I believe the gain in your amp is adjustable. Read the link I sent you.
(3) Use an SPL meter. It is possible that you are running into a frequency based issue? My class A amps all have a lot more distortion than the class A/B amps and subjectively this changes HOW I hear them. So, you need to measure how loud they are going. In addition, you might want to put in a microphone and figure out the frequency spectrum of the sound. Perhaps the Ncore amp is clean while the Plinnius starts to introduce some distortion that makes it "sound" louder?
(4) I ignore ASR.
@tonyEE I suggest building the Hypex. I know someone wandering into this discussion might read it as me bashing Hypex or even class D altogether, that's absolutely not what I'm trying to do.
Not to intentionally go even deeper into my subjective and even anecdotal impressions of what might be going on here, but let me give Hypex some due praise... I mentioned that I originally did this out of curiosity, I wanted to hear how these highly praised Hypex amps compared with one of the best A/B amps I've ever owned or heard. So I built 4 mono amps, the reason for 4 was to leave 2 stock, and play with the other 2 to compare. When I first built the stock amps, I was slightly impressed with how they sounded. But compared to my Plinius, they were a tad soft in the highs (I'll even say muffled). So I got a buffer board that allowed me to try different op-amps, and using the Sonic Imagery 994, I think I might prefer the Hypex over the Plinius in the highs.
And I want to reiterate (again) that the SPL at which the Hypex begins to fall off is insane, well beyond any level someone would normally listen. All I'm trying to do is quantify why, because based on my understanding of amplifier power and headroom, it shouldn't be this way.
I will measure the SPL of this phenomenon using white noise for both amps. I'm not sure how much help measuring the response of actual music would be, because it's tough to follow. I could use sweeps and watch that response, but I think using sweeps wouldn't help tell the whole story either.
As to cab asking about measurements... what's the point of doing that? There's nothing new about this amp, measurements for exactly what I built are all over the place, very easy to find. What you can't find is a measurement that shows a legitimate RMS rating. And I admittedly don't know how to measure for that.
Not to intentionally go even deeper into my subjective and even anecdotal impressions of what might be going on here, but let me give Hypex some due praise... I mentioned that I originally did this out of curiosity, I wanted to hear how these highly praised Hypex amps compared with one of the best A/B amps I've ever owned or heard. So I built 4 mono amps, the reason for 4 was to leave 2 stock, and play with the other 2 to compare. When I first built the stock amps, I was slightly impressed with how they sounded. But compared to my Plinius, they were a tad soft in the highs (I'll even say muffled). So I got a buffer board that allowed me to try different op-amps, and using the Sonic Imagery 994, I think I might prefer the Hypex over the Plinius in the highs.
And I want to reiterate (again) that the SPL at which the Hypex begins to fall off is insane, well beyond any level someone would normally listen. All I'm trying to do is quantify why, because based on my understanding of amplifier power and headroom, it shouldn't be this way.
I will measure the SPL of this phenomenon using white noise for both amps. I'm not sure how much help measuring the response of actual music would be, because it's tough to follow. I could use sweeps and watch that response, but I think using sweeps wouldn't help tell the whole story either.
As to cab asking about measurements... what's the point of doing that? There's nothing new about this amp, measurements for exactly what I built are all over the place, very easy to find. What you can't find is a measurement that shows a legitimate RMS rating. And I admittedly don't know how to measure for that.
I could be wrong, but I'm almost positive the gain isn't adjustable. You can select 12 or 27 dB, but no adjustments beyond that that I'm aware of.
ASR is great for measurements as long as you can read beyond the almost cultish mentality in some of the members. I understand the flaws in reading subjective perceptions about equipment, but I think subjective perceptions are still valid.
Setting the preamp to 15 and playing white noise, the Plinius is 79.3 dB, while the Hypex is 72.7 dB at the same preamp volume, obviously that's a massive swing.
Not saying this is showing a flaw anywhere, this is based on the Plinius gain being 37 dB, while the Hypex amp's gain is 14 dB (not 27, I was wrong, it's 27 with the factory Hypex buffer, but the buffer I have now is actually 14). This huge difference in gain might be exactly what I'm hearing.
And I'm still fairly sure there is no way to adjust the gain, on the stock Hypex buffer you can choose either 27 or 14, using the buffer I have installed now I can choose either 14 or 7.
Now we can debate merits of lower gain settings on amplifiers and whether or not this a problem at all 🙂
Not saying this is showing a flaw anywhere, this is based on the Plinius gain being 37 dB, while the Hypex amp's gain is 14 dB (not 27, I was wrong, it's 27 with the factory Hypex buffer, but the buffer I have now is actually 14). This huge difference in gain might be exactly what I'm hearing.
And I'm still fairly sure there is no way to adjust the gain, on the stock Hypex buffer you can choose either 27 or 14, using the buffer I have installed now I can choose either 14 or 7.
Now we can debate merits of lower gain settings on amplifiers and whether or not this a problem at all 🙂
I think its related to the power supply, the Plinius SB-301 has two huge transformers and I think they have plenty of juice.
I'm wondering...
I fired up the XA252 SIT ( aka Macho ) yesterday....
I cranked it up quite a bit and it didn't seem to get loud... while the Sissy ( half the power, much less gain ) does get loud.
Someone made the comment that distortion makes it seem loud, while lack of distortion never makes it seem loud.
Could it be the Plinius starts to put out some distortion while the Hypex does not? So, you "feel" like he Hypex is just not "getting louder"?
I fired up the XA252 SIT ( aka Macho ) yesterday....
I cranked it up quite a bit and it didn't seem to get loud... while the Sissy ( half the power, much less gain ) does get loud.
Someone made the comment that distortion makes it seem loud, while lack of distortion never makes it seem loud.
Could it be the Plinius starts to put out some distortion while the Hypex does not? So, you "feel" like he Hypex is just not "getting louder"?
OK... what is the gain in your preamp then?
I'm using a Conrad Johnson ET3SE with a 20Vrms output. The volume is a step ladder affair with a front panel display.
So, I'm finding out that an 18w amplifier seems to get louder than a 36W amp.. with the latter having lower distortion. The gains are 12 db vs 20 db respectively.
With my preamp, I have lots of voltage output so I actually prefer the lower gain affair... but I also need more power (!!)
So, in your case, it could be a case of the distortion components of each amp are different.
Can you swing the preamp louder to set the level of both of your amps to swing the same loudness out of the speakers?
And, yes, I did notice the lower gain of the Hypex.
I'm using a Conrad Johnson ET3SE with a 20Vrms output. The volume is a step ladder affair with a front panel display.
So, I'm finding out that an 18w amplifier seems to get louder than a 36W amp.. with the latter having lower distortion. The gains are 12 db vs 20 db respectively.
With my preamp, I have lots of voltage output so I actually prefer the lower gain affair... but I also need more power (!!)
So, in your case, it could be a case of the distortion components of each amp are different.
Can you swing the preamp louder to set the level of both of your amps to swing the same loudness out of the speakers?
And, yes, I did notice the lower gain of the Hypex.
I hate that I can't quote the last comment.
Gain vs output is definitely tricky. My preamp is 18 dB... The Plinius is 38 dB via XLR (insanely high) and Hypex NCx500 is 27 dB (pretty average).
Gain vs output is definitely tricky. My preamp is 18 dB... The Plinius is 38 dB via XLR (insanely high) and Hypex NCx500 is 27 dB (pretty average).
I
Just looked up your Conrad Johnson preamp... 25 dB gain, that's a lot. Be careful if you ever get a solid state amp, make sure it's a lower gain amp. Like 27 would be the max.
@Fr3dJa, have you actually read anything here? If so you should work on your comprehension. Your post has absolutely nothing to do with anything I stated. And I'm not a professional amp builder, if you read (or maybe if you understood) any of this you'd know that as well.
And your statement is erroneous, amps playing louder don't always sound better. That's a broad generalization that doesn't always apply. I can only assume you're not a professional since you're not aware of that?
FWIW, I will measure this and figure out what the reality is here. I posted this before I knew that class D power ratings was such a heated debate, and I really don't want to go down that road because I really don't care about class D vs A vs A/B vs valves. I was hoping for a quick answer (from someone that understands amplifiers more than me since I'm not a professional amplifier builder), but it won't be that simple. I'll hook this to the oscilloscope, figure out clipping and try to figure out power and report back.
Hmm.. well, playing either of my Conrad Johnson preamps ( both with high gain and 20Vrm output ) through an F4 sounds marvelous
@mattsk8. More than just a scope, perhaps you need to look for the distortion components at high volumes. As I noted earlier, perhaps the lack of distortion makes it seem as it is not as loud?
F4 is a power buffer, not a "normal" power amplifier , so your remark does not make sense.
Measuring distortion is where I'll be flying blind, I wish I was equipped to do that but at this point I'm not. I do know the Hypex is (extremely) low distortion so I think some of what you're saying might be at play here, but I can get to a threshold with the Hypex where it literally quits getting louder.
My concern is that this might be near clipping, and I don't want to smoke a pair of tweeters. But I'm also not sure (yet) how Hypex amplifiers manage clipping, perhaps that threshold I reach of limited output is some sort of anti-clipping function? But it doesn't mention much at all about that in the PDF for the amp. This is why I want to measure them with an oscilloscope, then I'll see exactly what point these clip (if they clip).
It's a current amplifier... The point being that the statement made was made in suis generis hence all I had to do was to come up a single fact to invalidate the claim.
Ergo... F4.
QED.
The NC500 used in the FA501 plate amp has 500w rms @4ohm and 400w rms @2ohm
It powers 2 12 inch scan speak subwoofers without problems in parallel conection.
It powers 2 12 inch scan speak subwoofers without problems in parallel conection.
You will need to take two measurements under the said conditions. NCORE amplifiers has a much more controlled circuit that performs clamping saturation as output nears the rails, he could be perversing short term distortion peaks as louder, the clamp will naturally shape this.