Need a 5 channel amp.

[Andrein]

In my house all amps i had used to hum. Even my old Yamaha 860 which i guess silent for many people. A1070 which is rated higher is at the same time more quiet. MCA 525 is the best so far in this respect. Indeed silent. Even in my house. It is probably a combination of amp design and the house/other equipment. Some variation in transformer quality within model probably also takes place.

 

[snakeeyes]

In my house all amps i had used to hum. Even my old Yamaha 860 which i guess silent for many people. A1070 which is rated higher is at the same time more quiet. MCA 525 is the best so far in this respect. Indeed silent. Even in my house. It is probably a combination of amp design and the house/other equipment. Some variation in transformer quality within model probably also takes place.

My Yamaha A2060 has no hiss or hum. I’m wondering if the Monolith 3 would work on my existing 15A circuit. (That just has the one smaller transformer). My panel is 30ft away but full so a sub panel is the next upgrade if I need more circuits. If I take the load off the front 3 ch then the 2060 can power the other 6 ch in 5.1.4. Originally wanted Outlaw 5000 but don’t think it would be much of an upgrade whereas the Monolith 3 would be.

 

[Verdinut]

My Yamaha A2060 has no hiss or hum. I’m wondering if the Monolith 3 would work on my existing 15A circuit. (That just has the one smaller transformer). My panel is 30ft away but full so a sub panel is the next upgrade if I need more circuits. If I take the load off the front 3 ch then the 2060 can power the other 6 ch in 5.1.4. Originally wanted Outlaw 5000 but don’t think it would be much of an upgrade whereas the Monolith 3 would be.

It would normally work on a 15 amp circuit, unless you were driving very inefficient speakers and you were listening at a big distance and at very high SPL.

With my system, I use 3 QSC DCA 1222 amplifiers in an active bi-amping configuration to drive my front speakers. The 3 subs have a 4 ohm impedance and the parallel connected midranges and tweeter drivers also. On top of that, a DCA 1824 (4 channel amp) that drives the surround and surrond back speakers (8 ohms) and the Marantz SR5010 used as a pre-pro are also connected to the same 15 amp circuit. I never had a problem because I rarely listen to SPLs higher than 85 dB. Note that the 3 DCA 1222s have a power rating of 325w/ch at 4 ohms and the DCA 1824 has a power rating of 200w/ch at 8 ohms.

 

[Out-Of-Phase]

Talk about quietness, I can tell you my quietest amp is the one I built recently. Mr. Pass's 5 W class A amp. The transformer is completely silent even if you glue both ears to the chassis, you know why??

Regardless, this little thing has no hiss either, but I have to do something to deal with the turn on/off noise that is expected for the particular design (the price to pay for simplicity I guess..).

I’ve always been interested in building one of these amps myself. I guess what stops me is my attitude towards anything I see as “audiophile”. Maybe I’ll try one anyway one of these days. Projects like this are always fun.

 

[PENG]

In my house all amps i had used to hum. Even my old Yamaha 860 which i guess silent for many people. A1070 which is rated higher is at the same time more quiet. MCA 525 is the best so far in this respect. Indeed silent. Even in my house. It is probably a combination of amp design and the house/other equipment. Some variation in transformer quality within model probably also takes place.

That is true, some amps are more prone to certain harmonics and dc offsets so a quieter amp under ideal or near ideal conditions could be noisier under certain less than ideal conditions.

 

[PENG]

I’ve always been interested in building one of these amps myself. I guess what stops me is my attitude towards anything I see as “audiophile”. Maybe I’ll try one anyway one of these days. Projects like this are always fun.

It is quite expensive to build, $317 for the kit, add on top shipping and two AC Infinity fans and taxes, the total cost would approach $400, for 8 WPC (increased from 5 W with the new and improved 24 V power supply).

To get it up to the more useful 25-30 W range, you can build two and bridge them, or build the 25 W F5 but run at higher rail voltage. (my next project).

 

[KEW]

I did the @KEW (if he has free time I hope he will check my findings) thing, that is, compared the sizes of their transformers by scaling the photos.
The Monolith transformers are physically larger, approx. 17-20 % in volume.

Sorry it took me so long to get around to this, but I got a significantly different result so wanted to double check when I had time to be extra careful.
My estimates put the larger Monolith transformer at 5.875" diameter by 2.75" thick and the smaller at 5.5" diameter by 2.75" thick.
Using (pi X d X d)/4 to calculate volume, I get 74.6 and 65.3 cubic inches or 139.9 cubic inches for the pair.

For the Anthem, my estimates are 5.625" diameter and 2" thick. Volume is 49.7 cu. in. each or 99.4 for the pair.

Thus I end up with the Monolith having 40% more volume than the Anthem.

I must say that the perspective of the Anthem image I found was awkward to work with, so I don't have as much confidence in my estimates. If someone has one, they may be able to check my numbers and see if I am off by much.

On the other hand, while the Monolith we are discussing is a 5 channel amp, the transformers are chosen to support the demands of their 7 channel amp, so it is curious to note that the ratio of 7 to 5 is 1.4 ... or 7 is 40% more than 5. Looking at it that way, the 5 channel Anthem and the 7 channel Monolith have very much identical transformer volume per channel!

Edit - Like I said the Anthem image was at a difficult angle and since the edges of the transformer are rounded, it is hard to get a good measure. I think it is reasonable that the thickness of the Anthem transformer might be 2.25". If so, that would increase volume by 1/8 or to 111.8 cu. in. for the pair. This would make for a 25% difference.

So I would want to call it between 25% and 40% just to hedge my bets!

 

[PENG]

Sorry it took me so long to get around to this, but I got a significantly different result so wanted to double check when I had time to be extra careful.
My estimates put the larger Monolith transformer at 5.875" diameter by 2.75" thick and the smaller at 5.5" diameter by 2.75" thick.
Using (pi X d X d)/4 to calculate volume, I get 74.6 and 65.3 cubic inches or 139.9 cubic inches for the pair.

For the Anthem, my estimates are 5.625" diameter and 2" thick. Volume is 49.7 cu. in. each or 99.4 for the pair.

Thus I end up with the Monolith having 40% more volume than the Anthem.

I must say that the perspective of the Anthem image I found was awkward to work with, so I don't have as much confidence in my estimates. If someone has one, they may be able to check my numbers and see if I am off by much.

On the other hand, while the Monolith we are discussing is a 5 channel amp, the transformers are chosen to support the demands of their 7 channel amp, so it is curious to note that the ratio of 7 to 5 is 1.4 ... or 7 is 40% more than 5. Looking at it that way, the 5 channel Anthem and the 7 channel Monolith have very much identical transformer volume per channel!

Edit - Like I said the Anthem image was at a difficult angle and since the edges of the transformer are rounded, it is hard to get a good measure. I think it is reasonable that the thickness of the Anthem transformer might be 2.25". If so, that would increase volume by 1/8 or to 111.8 cu. in. for the pair. This would make for a 25% difference.

So I would want to call it between 25% and 40% just to hedge my bets!

It is indeed difficult to get accurate results but it is fair to say the Monolith's are larger. If we split the difference, I would agree 25% would probably be a conservative (minimum) number.

I estimated for Andrein that the Anthem's were 750 VA, that was being very generous, they could be 530 VA based on pictures I saw for the previous generation, but I would also bet they increased them to about 600 VA, so if I were a betting man, I would also hedge my bet, say 600 to 650 VA each.

Now, time for some corroboration, the MCA 525's stated consumption is 1200 W (high/maximum). For class AB amplifiers, efficiency won't get much better than 70%
https://www.audioholics.com/audio-amplifier/amplifier-classes

Again let's be generous and assume 80%, then the maximum output of the MCA would be 960 W, that's 192 W, 5 channel driven, that's pretty close to the one channel driven rating of 225 W. Question is, can their efficiency be as high as 80%? If you drop it to 75%, then the 5 channel driven output would be 180 W.

Looking at the Monolith's specs, based on transformer VA rating, assuming 80 % efficiency again, they would have no problem delivering the specified 200 W, all 5 channel driven, in fact they can do so even if we assume a more realistic efficiency of say 50%.

So based on my educated guess, the Anthem will do better with 1 and 2 channel driven, but the Monolith would win in 5 channel driven, especially in terms of the "continuous" rating.

Just a side note, Monolith/ATI also seem to have their own hypes such as:

ATI - "40% more efficient than EI type" That is ridiculously confusing no matter how one interprets its meaning. Ask any EE who knows something about transformer designs will tell you transformer efficiency, typically above 90%, E-I, toroid or other types, is not an issue at all.

Monolith - The VA ratings for the two transformer versions total 2055 VA for the 5X and 7X, whereas for the single transformer versions are 800 VA and 1025 VA for the 2X and 3X.

So their VA/W ratios are are all over the map, yet they are all specified 200 WPC, may be the amplifier output devices are the limiting factor, or something is/are? Or they exaggerated the VA ratings in some ways?

Looking at the Anthem P series, everything (breaker A rating, output watts, power consumption etc.) looks a lot more credible. For example, the P5 comes with two power cords, one for each transformer and the specs actually give you the 1 and all channel driven outputs, still no transformer VA rating given..

 

[Andrein]

It is indeed difficult to get accurate results but it is fair to say the Monolith's are larger. If we split the difference, I would agree 25% would probably be a conservative (minimum) number.

I estimated for Andrein that the Anthem's were 750 VA, that was being very generous, they could be 530 VA based on pictures I saw for the previous generation, but I would also bet they increased them to about 600 VA, so if I were a betting man, I would also hedge my bet, say 600 to 650 VA each.

Now, time for some corroboration, the MCA 525's stated consumption is 1200 W (high/maximum). For class AB amplifiers, efficiency won't get much better than 70%
https://www.audioholics.com/audio-amplifier/amplifier-classes

Again let's be generous and assume 80%, then the maximum output of the MCA would be 960 W, that's 192 W, 5 channel driven, that's pretty close to the one channel driven rating of 225 W. Question is, can their efficiency be as high as 80%? If you drop it to 75%, then the 5 channel driven output would be 180 W.

Looking at the Monolith's specs, based on transformer VA rating, assuming 80 % efficiency again, they would have no problem delivering the specified 200 W, all 5 channel driven, in fact they can do so even if we assume a more realistic efficiency of say 50%.

So based on my educated guess, the Anthem will do better with 1 and 2 channel driven, but the Monolith would win in 5 channel driven, especially in terms of the "continuous" rating.

Just a side note, Monolith/ATI also seem to have their own hypes such as:

ATI - "40% more efficient than EI type" That is ridiculously confusing no matter how one interprets its meaning. Ask any EE who knows something about transformer designs will tell you transformer efficiency, typically above 90%, E-I, toroid or other types, is not an issue at all.

Monolith - The VA ratings for the two transformer versions total 2055 VA for the 5X and 7X, whereas for the single transformer versions are 800 VA and 1025 VA for the 2X and 3X.

So their VA/W ratios are are all over the map, yet they are all specified 200 WPC, may be the amplifier output devices are the limiting factor, or something is/are? Or they exaggerated the VA ratings in some ways?

Looking at the Anthem P series, everything (breaker A rating, output watts, power consumption etc.) looks a lot more credible. For example, the P5 comes with two power cords, one for each transformer and the specs actually give you the 1 and all channel driven outputs, still no transformer VA rating given..

I think we cant quite compare monolith and mca 525 in terms of w per channel from transformer raw numbers perspective. Remember mca has a shared pool of transformers and capacitors. So it is not apple to apple. Monolith can hit the limit sooner if something crazy will hapen in one of the channels.

I can open my mca 525 and measure transformers exactly. Just a bit lazy)))

 

[PENG]

I think we cant quite compare monolith and mca 525 in terms of w per channel from transformer raw numbers perspective. Remember mca has a shared pool of transformers and capacitors. So it is not apple to apple. Monolith can hit the limit sooner if something crazy will hapen in one of the channels.

I can open my mca 525 and measure transformers exactly. Just a bit lazy)))

Hey Andrein, I said that too, didn't I say the MCA would do better in one, two channel driven? That's because I know the transformers are shared. That's also why they have superb dynamic ratings. There are pros and cons, it does have poorer channel separation, for example. You don't have defend the MCA in every turn when I simply tried to address the technical side when questions popped up, I own one, love it and would buy it again if my failed. I would definitely go for the MCA 225 though because yes I love raw VAs and uF, and separation, even though the advantages are just on paper.

Note: No need to open and measure as you may void the warranty, you can only go by size if comparing transformers of the same make, same design etc. I am comfortable with my educated guess because I considered all available specs for corroboration. The numbers won't be exact, but will be in the ball park.

 

[Andrein]

I dont defend mca 525))) I would not spend £3999 on it at the time if Monolith 5 supported european 240v/50hz or if Emo xpa 5 did not sound sow awfull to my ear.

I just had to try something else and luckily as a bonus mca appeared completely silent in my house. Otherwise would not bother spending twice.

 

[Andrein]

Thanks for reminding me about warranty. I almost opened it last week)))

 

[KEW]

Monolith - The VA ratings for the two transformer versions total 2055 VA for the 5X and 7X, whereas for the single transformer versions are 800 VA and 1025 VA for the 2X and 3X.

So their VA/W ratios are are all over the map, yet they are all specified 200 WPC, may be the amplifier output devices are the limiting factor, or something is/are? Or they exaggerated the VA ratings in some ways?

So we have the following VA/channel:
2X - 400 (or 512*) VA/channel
3X - 331 (or 410*) VA/channel
5X - 400 (or 451*) VA/channel
7X - 292 (or 322*) VA/channel
*Values in parentheses are based on AH review quoted below.

Edit: Where did you get those values?
There is a conflict.
Gene made the following statement in the 7 channel Monolith review:

The power modules are constructed as monoblocks; each having 6 output devices per channel and 4x 5,600uF, 80V capacitors in parallel to yield a total of 22,400uF of capacitance per channel. The parts are rated at 85 deg C which,is pretty standard fair for a product of this caliber. The entire amp is fed off one large 800VA transformer. This amp has all the right hardware to deliver its rated power honestly, and then some. The same principles remain as you move up the model line-up with their Monolith7 boasting dual torrodial power transformers (1,230VA and 1,025VA) to maintain rated power with all channels driven.

I wish he had actually measured the 7 channel version to see how well it supports 5 or 7 channels at once and whether it really needs two power cables to support the full rated load as the Anthem P series uses.

 

[KEW]

I dont defend mca 525))) I would not spend £3999 on it at the time if Monolith 5 supported european 240v/50hz or if Emo xpa 5 did not sound sow awfull to my ear.

I just had to try something else and luckily as a bonus mca appeared completely silent in my house. Otherwise would not bother spending twice.

The way I look at this, it is pretty much an academic discussion!
Amplifiers are a mature science and both Anthem and ATI know how to do it well!

Unless you have some insanely power-hungry speakers (like Gene's Status Acoustics 8T's),either of these amps should do fine as far as outputting enough clean power.

However, something like transformer hum is understandably a deal-killer if it is loud enough to be a distraction, so as you say, that is good reason to pony up the bucks for the Anthem. That combined with having to add external transformers to get the power from 240 to 120 is plenty of reason to switch to something else. (BTW, the Monolith is the only amplifier I have that you cannot simply plug in 240V and have it work!) I assume this was a cost cutting measure by Monolith's request.
I have to wonder if you could have gotten Monolith/ATI to address the hum?
IIRC, you ran the risk of having to pay international shipping both ways to find out if they could address the problem, and I don't blame you for not wanting to get into that! The prospect of potential shipping damage alone would make me think twice, and the finger pointing between UPS and "Her Majesty's Royal Courier Service" could be very aggravating!

One thing that really impresses me about the Anthem is they give it a 600Watts RMS specification into 2 ohms (20-20k @ 1% THD)!
I'm not sure I have ever seen a 2 ohms RMS rating for an amplifier!

I wonder how the Monolith would fare for RMS at 2 ohms?

 

[KEW]

I don't defend mca 525))) I would not spend £3999 on it at the time if Monolith 5 supported european 240v/50hz or if Emo xpa 5 did not sound so awful to my ear.

I wonder what was wrong with the Emo.
Dan Laufman also knows how to design an amp, and there are enough well seasoned audio geeks buying their gear without complaint that I have to believe you got a defect. Always a chance that you have an exceptional ear/sensitivity to whatever it was, but if it was pretty obvious, I'd assume defective!

 

[PENG]

I dont defend mca 525))) I would not spend £3999 on it at the time if Monolith 5 supported european 240v/50hz or if Emo xpa 5 did not sound sow awfull to my ear.

I just had to try something else and luckily as a bonus mca appeared completely silent in my house. Otherwise would not bother spending twice.

I keep forgetting the UK price. Anthem is a short drive for me if I can buy factory direct..

 

[PENG]

Thanks for reminding me about warranty. I almost opened it last week)))

I can open mine, warranty has expired anyway.

 

[PENG]

One thing that really impresses me about the Anthem is they give it a 600Watts RMS specification into 2 ohms (20-20k @ 1% THD)!
I'm not sure I have ever seen a 2 ohms RMS rating for an amplifier!

That's for one channel driven and I believe only the P series can do it for real, not the A and MCA series.

The MCA's maximum power consumption is 600 W, vs the P2's 1800 W, you do the math. Can't have output > input can you? See what I meant by hypes..

The P series claimed it can survive a short cct. but I believe they can, for a short moment, the breaker would trip anyway.

 

[mtrycrafts]

...
I'm not sure I have ever seen a 2 ohms RMS rating for an amplifier!...

The Yamaha MX-1000 gives dynamic power into 2 Ohms of 960 watts and 1 Ohm of 1000Watts.
Does not give average power below 4 Ohms though.

 

[KEW]

The Yamaha MX-1000 gives dynamic power into 2 Ohms of 960 watts and 1 Ohm of 1000Watts.
Does not give average power below 4 Ohms though.

Yeah, I see lots of dynamic power ratings for 2 ohms and even 1 ohm (especially for pro amps). It is the FTC RMS watts rating at 2 ohms that astounded me (but it is not so astounding now that PENG pointed out the fallacy of it)!