Two Power Amps: Same/Similar on paper - will they sound the same?

[zandaman]

Hi!

I have a quick question. I'm interested in the Arcam PA 720 (https://www.arcam.co.uk/products,HDA,Power-Amplifier,PA720.htm) and the Monolith 7 channel power amp (https://www.monoprice.com/product?p_id=14566)

Both power 7 channels. The Arcam is class G. The Monolith is class A/B. The Arcam is rated at 100W when used with 7 8-ohm speakers. I believe the Monolith is 200W for 7 8-ohm speakers.

The Arcam is $3,000. The Monolith is $1,599.

What other features will distinguish these amps? Most importantly, will there be an appreciable difference in sound between them, with all else being equal? Will the Arcam be worth the markup vs the Monolith?

Additional Note: I will be using an Arcam AVR

 

[Gmoney]

Amps shouldn’t color the sound.

 

[lovinthehd]

I can't think of any good reason to get the Arcam unless there's some matching aesthetic that fits into your preferences for the Arcam....

 

[zandaman]

I can't think of any good reason to get the Arcam unless there's some matching aesthetic that fits into your preferences for the Arcam....

Will there be an auditory difference though? Based on the components? Class G vs Class A/B?

 

[lovinthehd]

Will there be an auditory difference though? Based on the components? Class G vs Class A/B?

I wouldn't expect topology of the amp to be a concern unless it's poorly executed. Doesn't seem that way from either company's reputation. I can't tell the difference in my Class D, G or AB amps....and I prefer value so the Monolith would be my choice (made by ATI so hard to fault its cred).

 

[AcuDefTechGuy]

No auditory sound quality difference unless your speakers require a lot more than 100W/8 ohms. Then the Arcam might have a problem.

Definitely no good reason to spend twice as much to get half as much power, especially when the Monolith is built by ATI, which I regard above Arcam.

 

[Verdinut]

The Arcam is $3,000. The Monolith is $1,599.
What other features will distinguish these amps? Most importantly, will there be an appreciable difference in sound between them, with all else being equal? Will the Arcam be worth the markup vs the Monolith?

No, you would be wasting your money getting the Arcam. The wiser decision is to opt for the Monolith.

 

[zandaman]

No, you would be wasting your money getting the Arcam. The wiser decision is to opt for the Monolith.

Here's another question - would it make more sense to get a 7 channel amp for the bed level, or a 4 channel amp for atmos? If I go for the second option, I'd use the receiver's channels to power the bed level speakers.

Would it be a waste to go for a 7 channel amp and not utilize all the Arcam AVR 550's built-in channels? Or would it be a waste of money to buy the 4 channel amp? The 4 channel amps that I've been looking at cost between 1400-1500 dollars, close to the price of the Monolith.

What do you think? Thanks!

 

[Verdinut]

Here's another question - would it make more sense to get a 7 channel amp for the bed level, or a 4 channel amp for atmos? If I go for the second option, I'd use the receiver's channels to power the bed level speakers.

Would it be a waste to go for a 7 channel amp and not utilize all the Arcam AVR 550's built-in channels? Or would it be a waste of money to buy the 4 channel amp? The 4 channel amps that I've been looking at cost between 1400-1500 dollars, close to the price of the Monolith.

What do you think? Thanks!

I would suggest you get the Monolith 5 channels amp then. A product that has excellent specs and reliability. You could drive the left and right surround speakers with the 2 remaining channels and use the Arcam for the Atmos.

 

[zandaman]

I would suggest you get the Monolith 5 channels amp then. A product that has excellent specs and reliability. You could drive the left and right surround speakers with the 2 remaining channels and use the Arcam for the Atmos.

If I understood you correctly, you said use the 5 channel amp for ear level speakers, and the receiver for the atmos?

But since I have 7, not 5, ear level speakers, are you saying 2 surrounds should be powered by the receiver? Wouldn’t that cause a disparate experience?

With regards to the 4 channel amps I was considering - I was looking at an Arcam or an NAD.

 

[lovinthehd]

I'd also just worry about the channels that need the most amplification, mains for the most part, maybe surrounds, but for rear surrounds and Atmos channels I'd just let the avr worry about it. What do you "disparate" experience?

 

[zandaman]

Disparate as in the ear level speakers powered by different amps with different power levels.

 

[lovinthehd]

Disparate as in the ear level speakers powered by different amps with different power levels.

That would be taken care of when you level match/calibrate your system (avr/external amp).

 

[zandaman]

So you’re saying the 5 or 7 channel would be the way to go, instead of a dedicated 4 channel amp for the atmos right?

 

[lovinthehd]

So you’re saying the 5 or 7 channel would be the way to go, instead of a dedicated 4 channel amp for the atmos right?

The load on the channels outside of the front three tend to be minimal, I've always let my avrs handle surrounds even if I'm using power amps on the mains. Don't see the point in buying special amps for such channels, particularly rear surrounds or atmos channels....

ps altho if the surrounds were particularly low sensitivity or was using all-channel stereo modes....that could be a reason to have external amps on those channels....

 

[zandaman]

This is all very helpful information! Thank you folks!!

 

[supraman408]

Are you guys recommending the Monolith based on its performance and price point? If both were the same price, which would you get? Apologize if Im jacking the forum but doing some research before I purchase. I went to BestBuy and the Magnolia Rep recommended the Arcam PA720 Power Amp for my system (BW 702 S2 floor speakers, BW 705S2 bookshelves, BW HTM71 S2 center,, REL T-9I sub and Marantz SR5015 receiver). I have the employee discount and can get the Arcam PA720 for $1800. Performance wise, is the Monolith better than the Arcam?
Thanks!

 

[PENG]

Here's another question - would it make more sense to get a 7 channel amp for the bed level, or a 4 channel amp for atmos? If I go for the second option, I'd use the receiver's channels to power the bed level speakers.

Would it be a waste to go for a 7 channel amp and not utilize all the Arcam AVR 550's built-in channels? Or would it be a waste of money to buy the 4 channel amp? The 4 channel amps that I've been looking at cost between 1400-1500 dollars, close to the price of the Monolith.

What do you think? Thanks!

If you can get a high quality 4 channel amp, then you can use the Arcam to power the surround and Atmos channels. That would be the most efficient way, because your AVR should be able to drive the other channels without any issue, unless they are position further away than the front channel speakers and/or have much lower sensitivity.

For the best specs possible for such an amp, I would consider the Hypex or Purifi based amps. Examples:

AT52XNC Amplifiers (ati-amp.com)

That's the expensive option, but may be @AcuDefTechGuy could get you a good deal if you asked him.

Otherwise as others have suggested, the Monolith 200WX5 appears to be a good option.

With the questionable Arcam's preamp output, you probably should avoid power amps with less than 28 dB gain.

In all likelihood, a good quality class AB, or G power amp won't be the bottleneck in terms of audio performance specs.

 

[PENG]

Will there be an auditory difference though? Based on the components? Class G vs Class A/B?

Not if the amps are rated for say 2X or more than the power you need and have distortions below the threshold of audibility (typically 0.1%, but the lower the better, such as 0.01-0.05%) under the worst conditions.

So you should use a calculator to estimate your power need if you want to be sure.

To you thread title question "
Two Power Amps: Same/Similar on paper - will they sound the same?"

I would say the answer is, it depends. For example, if they both have THD+N at 1%, then there may or may not be auditory difference depending on other factors. If they both have THD+N at 0.005%, then there most likely won't be any auditory difference unless being compared in an anechoic room with the best source being played through the best playback device to speakers with the best resolution etc etc...

People will hear difference between even amps designed for accuracy regardless, because they have read reviews, forum talks etc., and that play tricks on their minds. If they can't see which one's playing, then usually the difference heard would disappear.

 

[TLS Guy]

Hi!

I have a quick question. I'm interested in the Arcam PA 720 (https://www.arcam.co.uk/products,HDA,Power-Amplifier,PA720.htm) and the Monolith 7 channel power amp (https://www.monoprice.com/product?p_id=14566)

Both power 7 channels. The Arcam is class G. The Monolith is class A/B. The Arcam is rated at 100W when used with 7 8-ohm speakers. I believe the Monolith is 200W for 7 8-ohm speakers.

The Arcam is $3,000. The Monolith is $1,599.

What other features will distinguish these amps? Most importantly, will there be an appreciable difference in sound between them, with all else being equal? Will the Arcam be worth the markup vs the Monolith?

Additional Note: I will be using an Arcam AVR

The monolith is the better bet. Class G power supplies are horribly complex and highly failure prone. I always advise giving them a wide berth. The main issue in power amps is trying to asses reliability, and that is all over the amp in that genre. In general the simpler, and the less the part count, the better off you are.