Parasound A51 owners chime in..

[Pogre]

My input on the Ultra Towers, only buy them if you can pull them OUT from your soundstage wall IE front wall a minimum of 2’ optimal 3’ + at least 18” from corners.. Those side 8” passive radiators indeed act like additional small subs..
Doing this creates a massive deep soundstage w/zero boomy bloat from trapped standing waves etc etc

I have mine setup 14’ apart 2.5’ out & 18” corners..

That is true. They do like a little room breathe, but they sure do sound nice dialed in.

 

[Atlas-Athena]

She got here a day early! Jeez built like Panzer tank holy hell!!! Stunning… Latest version sadly doesn’t come w/Red Light behind P But still what a looker!!


Here I’ll add few pix unboxed her (Think tore my sack lol)

Have to make room & install in my rack this weekend or maybe Friday..
Edited some pix. Rhodesian ridgeback of Amps…

 

[Hetfield]

Man Parasound builds nice stuff. I'm jealous, would love to have a high end amp like that although my older Parasound amp is still kicking ass. Have fun with that beauty, great choice man.

Sent from my Pixel 4 XL using Tapatalk

 

[Atlas-Athena]

Well Parasound does not disappoint, I indeed hear definitive performance improvement vs Emotiva Gen 3 5 channel..

Among other differences the Parasound runs in class A power for the 1st 8 watts..

I found this here on Audioholics to hopefully explain my findings…

The review of A51 and A21 at audioholics.com (http://www.audioholics.com/productre...Amplifier.html) suggests 8 watts in Class A. See following quote:

"One of the most noteworthy operational functions of the Parasound A 21 and A 51 amplifiers are their Class A-A/B operation. The input and driver stages operate in pure Class A meaning that the transistors are turned on full all of the time. In essence there are two banks of transistors in the output stage, one of which is devoted to positive voltage and the other devoted to negative voltage. The point where the positive output transistors turn on while the negative transistors turn off (and vice versa) can cause nasty higher-order odd harmonic distortion (3rd, 5th, 7th, 9th, etc.) for which even very small amounts have been demonstrated as a primary cause of listening fatigue. In these Parasound amplifiers both the positive and negative transistors for each channel are always fully on – the definition of Class A operation - up to 8 watts output per channel. So, for the first 8 Watts of power, which exceeds the typical average power requirements for music, the output transistors are always on. For greater than 8 Watts, the transistors are in class A/B operation where they are partially on when they're not up for duty and fully on when they are up for duty."

 

[Hetfield]

Well Parasound does not disappoint, I indeed hear definitive performance improvement vs Emotiva Gen 3 5 channel..

Among other differences the Parasound runs in class A power for the 1st 8 watts..

I found this here on Audioholics to hopefully explain my findings…

The review of A51 and A21 at audioholics.com (http://www.audioholics.com/productre...Amplifier.html) suggests 8 watts in Class A. See following quote:

"One of the most noteworthy operational functions of the Parasound A 21 and A 51 amplifiers are their Class A-A/B operation. The input and driver stages operate in pure Class A meaning that the transistors are turned on full all of the time. In essence there are two banks of transistors in the output stage, one of which is devoted to positive voltage and the other devoted to negative voltage. The point where the positive output transistors turn on while the negative transistors turn off (and vice versa) can cause nasty higher-order odd harmonic distortion (3rd, 5th, 7th, 9th, etc.) for which even very small amounts have been demonstrated as a primary cause of listening fatigue. In these Parasound amplifiers both the positive and negative transistors for each channel are always fully on – the definition of Class A operation - up to 8 watts output per channel. So, for the first 8 Watts of power, which exceeds the typical average power requirements for music, the output transistors are always on. For greater than 8 Watts, the transistors are in class A/B operation where they are partially on when they're not up for duty and fully on when they are up for duty."

Absolutely, Parasound builds quality stuff, period. Their amps are well designed and sound great with plenty of power. Not much more to ask for really.

Sent from my Pixel 4 XL using Tapatalk

 

[Atlas-Athena]

Absolutely, Parasound builds quality stuff, period. Their amps are well designed and sound great with plenty of power. Not much more to ask for really.

Sent from my Pixel 4 XL using Tapatalk

After starting this thread & digesting all the feedback, I did not expect much more than a lateral move.. I couldn’t of been more wrong..

To sum it up the difference isn’t slight, or hard to hear it’s literally night & day, semantics aside I’ll leave it with an analogy latest Emotiva Gen 3 is like a Base model Corvette vs Parasound A51 = McLaren 720S

 

[Bonscott]

After starting this thread & digesting all the feedback, I did not expect much more than a lateral move.. I couldn’t of been more wrong..

To sum it up the difference isn’t slight, or hard to hear it’s literally night & day, semantics aside I’ll leave it with an analogy latest Emotiva Gen 3 is like a Base model Corvette vs Parasound A51 = McLaren 720S

As far as know neither the Parasound or the Emotiva color or alter the sound in anyway. IMO for there to be a “Night an Day” difference there had to be an issue with your system prior to changing Amplifiers

 

[Atlas-Athena]

f

As far as know neither the Parasound or the Emotiva color or alter the sound in anyway. IMO for there to be a “Night an Day” difference there had to be an issue with your system prior to changing Amplifiers

Lol zero problems..

The Audioholics review above notes such pertinent data IE the 1st 8 watts of pure A class power indeed makes a notable difference, not to mention rest of superior components used in Parasound etc

No need to beat the proverbial dead horse..
Opinions vary…

 

[PENG]

Yes that is a dead horse that people naturally would continue to beat!! The reality is, no one can dispute with what others heard, there are always some who will claim night and day difference between A and B, while others would claim a subtle difference, and some would say they couldn't even hear a difference at all unless one is pushed pass its limit; and that will never change regardless of any scientific basis including DBT results cited by the other side/camp.

I have compared an AVR-X3400H, using the same external DAC(s) including Oppo's Sonica, HA-1 and others, analog input, to the Halo A21 (with and without my Cambridge Audio preamp), and the results was, no difference heard, took some measurements with REW afterwards, and that showed very negligible difference in FR from 15 to 20,000 Hz. No one can dispute my findings either as that's what I heard (or not heard..), and the measurements were repeatable, could be done by anyone.

So I am happy the OP is happy with his purchase. I am too with mine, just for different reasons now, than when I first bought it.

 

[Cos]

I still have the A51 A31 in my system, and the Parasound amps do an incredible job. I recently acquired an ATI AT524nc from a local dealer and swapped it in for my mains and center. I did not get down to level matching and measuring as Peng did, but now that I have the mic to do it, I may test. That being said, I could not hear a difference between the two, and went with the ATI because I could not hear any tweeter buzz on my Persona 3Fs as I did with the Parasound. Like many on Audioholics, I have Audio OCD LOL. That and about a 40lb weight loss on the amp didn't hurt either.

 

[PENG]

I still have the A51 A31 in my system, and the Parasound amps do an incredible job. I recently acquired an ATI AT524nc from a local dealer and swapped it in for my mains and center. I did not get down to level matching and measuring as Peng did, but now that I have the mic to do it, I may test. That being said, I could not hear a difference between the two, and went with the ATI because I could not hear any tweeter buzz on my Persona 3Fs as I did with the Parasound. Like many on Audioholics, I have Audio OCD LOL. That and about a 40lb weight loss on the amp didn't hurt either.

I like my A21 except the weight and the transformer hum that is audible from 1-2 feet (about the same as my 4B SST) when the room is quiet. The AT52XNC series still uses linear power supplies but iirc you did find its transformer quieter than the Halo amps right?

 

[Cos]

I like my A21 except the weight and the transformer hum that is audible from 1-2 feet (about the same as my 4B SST) when the room is quiet. The AT52XNC series still uses linear power supplies but iirc you did find its transformer quieter than the Halo amps right?

Either I am going deaf, or it's pretty much dead silent from 1ft away, I have to put my ear on it, but no hum is heard. I lean towards quiet amp as I recently had my annual hearing test in april and I am above average hearing up to 15k hz. (That's the highest frequency they tested)

 

[highfigh]

Appreciate your knowledgeable input, having said that the frequency range on my Emotiva is (from their site)
300 watts RMS/channel; 20 Hz – 20 kHz; THD<0.1%; 8 Ohms; one channel driven.
550 watts RMS/channel; 20 Hz – 20 kHz; THD<0.2%; 4 Ohms; one channel driven.
300 watts RMS/channel; THD<0.1%; 8 Ohms;
two channels driven.

• Power Bandwidth (at rated power; 8 Ohm load): 20 Hz to 20 kHz (+ / – 0.1 dB).
• Broad Band Frequency Response: 5 Hz to 80 kHz +0/-2 dB.
• THD + noise: < 0.005%; at 100 watts RMS; 1 kHz; 8 Ohms.
• 
  It’s definitely bright, not neutral.. But admittedly I’m a novice here so please edify me etc appreciated.. Sean

I fail to see how an amp that has no specified indication of exceeding 0dB can be considered 'bright' when it only deviates by .1dB, which is such a small difference that it's inaudible. If the response drops slightly and rises again in a way that makes the highs subjectively louder than the range below it, I would have a problem using it or specifying it for a project. The fact that it does 5Hz-80KHz and misses total flatness above the normal range of hearing doesn't tell me that it's 'bright', either.

 

[Pogre]

f
Lol zero problems..

The Audioholics review above notes such pertinent data IE the 1st 8 watts of pure A class power indeed makes a notable difference, not to mention rest of superior components used in Parasound etc

No need to beat the proverbial dead horse..
Opinions vary…

I don't think you'd be able to tell which was which in a proper dbt.

For an anti placebo guy, you don't seem to understand much about it...

 

[Atlas-Athena]

I don't think you'd be able to tell which was which in a proper dbt.

For an anti placebo guy, you don't seem to understand much about it...

Thanks! Lol You guys are a bunch of old hens… Barring few normal 1’s here sheesh you’re worse than my X wife..

If you can stop pounding your chest for a brief moment? try reading this maybe it will help ease your mental constipation

Difference between Class A and Class AB amplifier - Acquitek

The difference between a Class A and a Class AB amplifier is simply the point at which the transistors are biased. In the case of Class A, the transistor is biased so that over the entire cycle of the RF input, the transistor is operating within its linear portion. In the case of Class AB, […]

www.acquitek.com

DIFFERENCE BETWEEN CLASS A AND CLASS AB AMPLIFIER
The difference between a Class A and a Class AB amplifier is simply the point at which the transistors are biased. In the case of Class A, the transistor is biased so that over the entire cycle of the RF input, the transistor is operating within its linear portion. In the case of Class AB, part of the cycle of the input is actually turning the transistor off.
This means that in the case of a Class A amplifier, the output is a faithful reproduction of the input signal whereas, in the case of Class AB some distortion is inevitable.
What does this mean and what do I need to consider when deciding which type of amplifier I need?
You should always choose a Class AB amplifier if possible, as it will be lower cost and more efficient. But whether you can do this will depend upon your specific application. If you are simply trying to deliver power to your application such as heating or agitating, then class AB will normally be sufficient.
However, if the fidelity of the signal that you are transmitting is important to you and you require information from this signal, then it is probable that you will require a Class A amplifier.
E&I rates all their amplifiers at their 1 dB compression point. (For the definition of 1 dB compression see: 1dB Compression) This is the point where the power gain is 1 dB below that of the linear range. The specification that we use to define the distortion is the harmonic content. The level of harmonic content is specified as dBc. This is the level of the harmonic signal below the fundamental, measured in dB. (For a definition of dB see decibel) The harmonic content of our amplifiers is typically specified at the rated power and for -25 dBc. Our amplifiers always have a push pull configuration which results in the 2nd harmonic being lower than the third. So whereas, the 2nd harmonic will be in the region of -40 dBc, it is possible that at some frequencies the 3rd could be as high as -25 dBc. We do not specify the harmonic content on our Class AB amplifiers. However, for a comparison point, the worst case 3rd harmonic for our Class AB amplifier could typically be -14 to -15 dB

 

[Atlas-Athena]

As PENG said maybe I can HEAR it or have more acute hearing than average? Geez move on guy…

 

[Andrein]

I bought Emotiva gen 3 5 channel amp 3-4 years ago. I did not like how my speakers sounded with it. All seemed the same in terms of levels, delays, etc to what I had with AVR and other amps I used before and after but the sound was worse than from avr I had at the time. Returned it in 2-3 days and bought Anthem MCA 525 instead and has been happy with it since then. AVR without Emotiva sounded the same as Anthem amp. Not sure what is wrong with Emotiva but to me it kills the idea of the power amp if the sound with it gets worse but not better or at least the same.

So, you are not alone in your opinion on Emotiva.

f
Lol zero problems..

The Audioholics review above notes such pertinent data IE the 1st 8 watts of pure A class power indeed makes a notable difference, not to mention rest of superior components used in Parasound etc

No need to beat the proverbial dead horse..
Opinions vary…

 

[Atlas-Athena]

I bought Emotiva gen 3 5 channel amp 3-4 years ago. I did not like how my speakers sounded with it. All seemed the same in terms of levels, delays, etc to what I had with AVR and other amps I used before and after but the sound was worse than from avr I had at the time. Returned it in 2-3 days and bought Anthem MCA 525 instead and has been happy with it since then. AVR without Emotiva sounded the same as Anthem amp. Not sure what is wrong with Emotiva but to me it kills the idea of the power amp if the sound with it gets worse but not better or at least the same.

So, you are not alone in your opinion on Emotiva.

Exactly it “Emotiva” sounded neutered vs Marantz internal amps & got me thinking hence ended up here.. Literally no if? Maybe? it’s bright period vs Marantz & Parasound etc

 

[Pogre]

As PENG said maybe I can HEAR it or have more acute hearing than average? Geez move on guy…

My apologies for upsetting you by, um... "beating my chest"(?). I never said I don't think you actually hear a difference. I just don't think it is what you think it is, nor do I think you really understand placebo or expectation bias. Your last couple of posts demonstrate that.

Again I believe you hear a difference, I just don't think you would under more controlled conditions.

 

[Atlas-Athena]

I still have the A51 A31 in my system, and the Parasound amps do an incredible job. I recently acquired an ATI AT524nc from a local dealer and swapped it in for my mains and center. I did not get down to level matching and measuring as Peng did, but now that I have the mic to do it, I may test. That being said, I could not hear a difference between the two, and went with the ATI because I could not hear any tweeter buzz on my Persona 3Fs as I did with the Parasound. Like many on Audioholics, I have Audio OCD LOL. That and about a 40lb weight loss on the amp didn't hurt either.

For what it’s worth I stumbled upon this in my parasound manual (possibly help you remove hum/buzz?)


AC Power Connections
We recommend that you plug your A 51 into the same AC wall outlet or power strip that pow- ers your other audio components, especially the preamplifier or system controller. Having all
the audio components on the same power circuit helps prevent hum caused by possible ground loops. The A 51 requires AC power that is continuous rather than switched on and off.
110 V - 120 V or 220 V - 240 V O

Cheers..