I’d like to add an amp, but don’t know if I really need one...

[Falstaff]

Greetings, Programs.

I wasn’t going to post this so soon, but there’s a sale on the amp l’m interested in and might need to pull the trigger in a week or two...

I’m currently running a Denon AVR-4520CI in my 7.1 home theatre that’s 2000 cubic feet. For years I’ve been debating about adding a modest-sized amp, and as I get closer to upgrading the AVR, I’ve noticed that the power of today’s AVR’s seems to be shrinking. My Denon is rated at 150 Watts with 2 channels running, but most of the AVR’s today that interest me are typically between 115 to 125 Watts. Because I don’t often crank the sound, but occasionally do, I thought adding a 7 channel amp that actually does 125 Watts for all 7 channels might add a nice increase to the soundstage. I really think something like a Monolith 7 or an Outlaw 7220 would be overkill and there would be an awful lot of wasted power, but what about a 125 Watt class D amp, do you think that it would much difference either with my current AVR or a new one with less power?

 

[AcuDefTechGuy]

I’m currently running a Denon AVR-4520CI in my 7.1 home theatre that’s 2000 square feet.

What? Your room is 2,000 S.F. like 50FT x 40FT ?

You mean more like 18FT x 20FT?

Unless you’re using the DSP Mode “Multi-Channel Stereo” or 11Ch Stereo or 9CH Stereo or 7CH Stereo, I don’t think your 125WPC AVR actually requires an external amp.

If you set your speakers to small and XO to 80-120 Hz and let your subs do all the heavy lifting, your AVR probably won’t need an external amp.

But many of us own external amps anyway whether our systems need them or not.

If somehow your speakers do need more amps, those speakers are probably your main front 3 speakers, not the 4 Surround speakers. So even the Outlaw 5000 amp will probably do.

Unless your room is 50FT x 40FT and you do sit 40FT away from your speakers.

 

[Falstaff]

What? Your room is 2,000 S.F. like 50FT x 40FT ?

You mean more like 18FT x 20FT?

Unless you’re using the DSP Mode “Multi-Channel Stereo” or 11Ch Stereo or 9CH Stereo or 7CH Stereo, I don’t think your 125WPC AVR actually requires an external amp.

If you set your speakers to small and XO to 80-120 Hz and let your subs do all the heavy lifting, your AVR probably won’t need an external amp.

But many of us own external amps anyway whether our systems need them or not.

If somehow your speakers do need more amps, those speakers are probably your main front 3 speakers, not the 4 Surround speakers. So even the Outlaw 5000 amp will probably do.

Unless your room is 50FT x 40FT and you do sit 40FT away from your speakers.

Sorry, meant 2000 cubic feet. It’s 13 feet wide by 19.5 feet long.

The only time I’ve really heard things sound bad, was when I was using 7CH stereo. I’ve just always read about “head room” and “clean power” and wondered if adding an amp to my current system might make a difference.

 

[PENG]

Greetings, Programs.

I wasn’t going to post this so soon, but there’s a sale on the amp l’m interested in and might need to pull the trigger in a week or two...

I’m currently running a Denon AVR-4520CI in my 7.1 home theatre that’s 2000 square feet. For years I’ve been debating about adding a modest-sized amp, and as I get closer to upgrading the AVR, I’ve noticed that the power of today’s AVR’s seems to be shrinking. My Denon is rated at 150 Watts with 2 channels running, but most of the AVR’s today that interest me are typically between 115 to 125 Watts. Because I don’t often crank the sound, but occasionally do, I thought adding a 7 channel amp that actually does 125 Watts for all 7 channels might add a nice increase to the soundstage. I really think something like a Monolith 7 or an Outlaw 7220 would be overkill and there would be an awful lot of wasted power, but what about a 125 Watt class D amp, do you think that it would much difference either with my current AVR or a new one with less power?

Reality check:

1. Double the power output only means 3 dB more sound pressure level (spl). Rule of thumb is, you need 10 dB more sound pressure level to give the sensation of the "twice as loud".

2. From 150 W to 120 W, there would make a difference in spl of only 0.97 dB, that's just one click on the volume dial!!

3. So in fact, relative to the quite powerful AVR-4520, the Monolith 7 or Outlaw 7220 will therefore not be "overkill". Going from 150 W to 200 W means you gain 1.24 dB, less than 2 clicks on the volume dial.

4. Hearsay will have you believe that even at very low level (fractional watts to a few watts),a more powerful amp will sound better, fuller etc., that's totally illogical, just think about it.

If you compare the measurements of the 4520 and Monolith 200X7, with two channels driven, into 8 and 4 ohms, the difference translated to spl is only between 1-1.5 dB. You will get more gain in the 5, 7 channel driven situations, 1.8-2.2 dB, significant to potentially make a difference if you listen to 7 Ch Stereo at or near reference level sitting far enough away, say > 11 to 12 feet.

So you can see that if you want the additional amp to make a real gain in power for you speakers, you really have to start with the Monolith 200X7, and up from there, not down.

Power output comparison:

AVR-4520CI
https://www.soundandvision.com/content/denon-avr-4520ci-av-receiver-test-bench

Two channel driven:
Into 4 ohms, the amplifier reaches 0.1% distortion at 237.5 watts and 1% distortion at 287.1 watts.
5 channel driven:
Into 8 ohms, 121.8 W

Monolith 200X7
https://forums.audioholics.com/forums/threads/i’d-like-to-add-an-amp-but-don’t-know-if-i-really-need-one.112629/

Two channel driven:
Into 4 ohms, the amplifier reaches 0.1% distortion at 345.6 watts and 1% distortion at 400.6 watts.
5 Channel driven:
Into 8 ohms, 185.8 W.

 

[AcuDefTechGuy]

Sorry, meant 2000 cubic feet. It’s 13 feet wide by 19.5 feet long.

The only time I’ve really heard things sound bad, was when I was using 7CH stereo. I’ve just always read about “head room” and “clean power” and wondered if adding an amp to my current system might make a difference.

Yeah, 7-CH Stereo or more is pretty tough on AVRs at high volume. Many AVRs and amps can handle 5-all-channel-driven, but not 7-all-channel-driven or more, especially at high volume.

But if that’s the case, I would get a 200-WPC amp like the Monoprice.

 

[snakeeyes]

That Monolith amp has me thinking. I like the 5 ch one. Thinking 5.1.4 sooner or later and my AVR can power 4 ceilings. Or even the 3 ch amp and my AVR can do sides and ceilings.

 

[lovinthehd]

7ch stereo mode is not one I use for listening, more for crowded parties where quality isn't an issue. What speakers do you have?

 

[KEW]

In case you have not thought of it, if you are buying the Monolith, I would get the Monolith 7, but only use 5 channels; using the 4520 for the other two channels. The Denon as a 2 channel amp will give you all of the headroom you could ask for and I guess it is probably more power than you would get out of channels 6 & 7 of the Monolith.
Sure, you could save $200 buying the Monolith 5, but a solid amp (like the ATI built Monolith) should last well beyond 20 years and having the extra 2 channels allows you some flexibility for the amp to grow with you... and $200 is really cheap for two channels of quality amplification.

Oh, if you do this, do a little research to determine how the two transformers in the Monolith 7 are shared between the 7 channels. It would make sense to drive 2 channels from the smaller transformer and 3 channels from the larger transformer! I'm betting the 4 channels to the left use the big transformer and the 3 channels to the right use the "less big" (it wouldn't be right to call it small) transformer.

 

[2channel lover]

Greetings, Programs.

I wasn’t going to post this so soon, but there’s a sale on the amp l’m interested in and might need to pull the trigger in a week or two...

I’m currently running a Denon AVR-4520CI in my 7.1 home theatre that’s 2000 cubic feet. For years I’ve been debating about adding a modest-sized amp, and as I get closer to upgrading the AVR, I’ve noticed that the power of today’s AVR’s seems to be shrinking. My Denon is rated at 150 Watts with 2 channels running, but most of the AVR’s today that interest me are typically between 115 to 125 Watts. Because I don’t often crank the sound, but occasionally do, I thought adding a 7 channel amp that actually does 125 Watts for all 7 channels might add a nice increase to the soundstage. I really think something like a Monolith 7 or an Outlaw 7220 would be overkill and there would be an awful lot of wasted power, but what about a 125 Watt class D amp, do you think that it would much difference either with my current AVR or a new one with less power?

Agree with post #2.

I'm a fan of keeping heat producing amps in their own enclosure, but it's a "want", not a need and that's likely the case with you. Nothing wrong with some extra power. I like the Outlaw 5000 and use your Denon to drive the other 2 surrounds....solid amp, reasonably priced...will take the load off the Denon for LCR + side surrounds...maybe you get a lot of use out of the rear surrounds...if so, go for the 7 ch.

 

[KEW]

Agree with post #2.

I'm a fan of keeping heat producing amps in their own enclosure, but it's a "want", not a need and that's likely the case with you. Nothing wrong with some extra power. I like the Outlaw 5000 and use your Denon to drive the other 2 surrounds....solid amp, reasonably priced...will take the load off the Denon for LCR + side surrounds...maybe you get a lot of use out of the rear surrounds...if so, go for the 7 ch.

Normally, I'd agree with you, but he is playing 7 channel stereo so each speaker is getting a full stereo signal and the peaks in SPL are much more happen at the same time for all 7 channels than in other modes (or for HT).

Hopefully, Falstaff will respond to Lovinthehd's question about which speakers he is using so we can get a better picture of his power demands.

 

[AcuDefTechGuy]

Normally, I'd agree with you, but he is playing 7 channel stereo so each speaker is getting a full stereo signal and the peaks in SPL are much more happen at the same time for all 7 channels than in other modes (or for HT).

Hopefully, Falstaff will respond to Lovinthehd's question about which speakers he is using so we can get a better picture of his power demands.

Not too long ago, a friend on the forum (no longer with us) posted a thread about his Denon (I think AVR-4311CI) shutting down when he played 7CH Stereo mode using Klipsch towers (rated something like 98dB/2.83/v) with other Klipsch speakers.

I believe he ended up adding an external 200 WPC amp also.

 

[KEW]

Not too long ago, a friend on the forum (no longer with us) posted a thread about his Denon (I think AVR-4311CI) shutting down when he played 7CH Stereo mode using Klipsch towers (rated something like 98dB/2.83/v) with other Klipsch speakers.

I believe he ended up adding an external 200 WPC amp also.

That is surprising, I generally think of Klipsch speakers as eliminating any power concerns (assuming competent/mainstream/normal gear)!

 

[AcuDefTechGuy]

That is surprising, I generally think of Klipsch speakers as eliminating any power concerns (assuming competent/mainstream/normal gear)!

Yeah, that's what we were all telling him too.

I think expecting any AVR to do 7Ch or 9Ch Stereo mode is asking for trouble.

I still like the Yamaha MX-A5000 since I would never use more than 2CH Stereo mode. But when Gene tested 7-Ch-driven, it went into protection mode.

So even if the speakers were 100dB/w/m, protection mode won't power them.

 

[PENG]

7ch stereo mode is not one I use for listening, more for crowded parties where quality isn't an issue. What speakers do you have?

In case you have not thought of it, if you are buying the Monolith, I would get the Monolith 7, but only use 5 channels; using the 4520 for the other two channels. The Denon as a 2 channel amp will give you all of the headroom you could ask for and I guess it is probably more power than you would get out of channels 6 & 7 of the Monolith.
Sure, you could save $200 buying the Monolith 5, but a solid amp (like the ATI built Monolith) should last well beyond 20 years and having the extra 2 channels allows you some flexibility for the amp to grow with you... and $200 is really cheap for two channels of quality amplification.

Oh, if you do this, do a little research to determine how the two transformers in the Monolith 7 are shared between the 7 channels. It would make sense to drive 2 channels from the smaller transformer and 3 channels from the larger transformer! I'm betting the 4 channels to the left use the big transformer and the 3 channels to the right use the "less big" (it wouldn't be right to call it small) transformer.

I agree with you the 200WX7 represents the best Watts/Dollars ratio, but the 200WX5 has the best VA/Watts ratio, that is, more transformer capacity per channel. The difference is insignificant but it is free, and it also make the amp less jam-packed, less interference, much lighter, and run cooler. For someone who is using a powerful AVR such as the 4520 or even the less powerful X4000H series, I thought the 200WX5 is better, mostly because it is lighter, and $200 for two more amp is still not a good deal if not used.

 

[snakeeyes]

I agree with you the 200WX7 represents the best Watts/Dollars ratio, but the 200WX5 has the best VA/Watts ratio, that is, more transformer capacity per channel. The difference is insignificant but it is free, and it also make the amp less jam-packed, less interference, much lighter, and run cooler. For someone who is using a powerful AVR such as the 4520 or even the less powerful X4000H series, I thought the 200WX5 is better, mostly because it is lighter, and $200 for two more amp is still not a good deal if not used.

I am very curious about the Monolith 3 vs Monolith 5. Are they different other than number of channels?

 

[KEW]

I am very curious about the Monolith 3 vs Monolith 5. Are they different other than number of channels?

Yes, the 5 is where the second transformer is added.
It is interesting that the pricing of the Monolith is essentially $1000 for 2 channels and another $100 for each channel after that but the actual cost involves a second transformer when you go to 5 channels. (I am using old prices - not sure that the new generation has the same price structure).

 

[snakeeyes]

Yes, the 5 is where the second transformer is added.
It is interesting that the pricing of the Monolith is essentially $1000 for 2 channels and another $100 for each channel after that but the actual cost involves a second transformer when you go to 5 channels. (I am using old prices - not sure that the new generation has the same price structure).

Okay so the Monolith 5 is worth it over the Monolith 3.

 

[KEW]

Okay so the Monolith 5 is worth it over the Monolith 3.

In a word, yes!

 

[PENG]

I am very curious about the Monolith 3 vs Monolith 5. Are they different other than number of channels?

3X200
Toroidal Transformers1 (1,025VA)

5X200
Toroidal Transformers2 (1,230VA and 1,025VA)

7X200
Toroidal Transformers 2 (1,230VA and 1,025VA)

Caps are the same in each case, 22,400 uF per channel

 

[Falstaff]

Thanks for all the replies. To answer some of you, I have Axiom speakers. I’ve been happy with them for many years and didn’t bother mentioning the brand due to the negative air surrounding them on this site in the past.

As for the Monolith or Outlaw amps, I’m certain I wouldn’t be able to use them without running a dedicated 20 amp line—something that would require far to much work than I’m willing to do. Thanks to Peng’s link to the bench test of the 4520–I was looking for one, but somehow didn’t see that myself—my belief that that AVR was plenty powerful while running 7 channels seems to be accurate. I have it in my head that I want no less than 100 Watts per 7 channels driven. The amp, though, is not really for this AVR. I’d like to buy a new model and have found that few today still offer the power of the 4520. Seems to me more these days are in the 115 to 125 Watt range, but that’s with only 2 channels running. Been looking at something like the Marantz SR7013 but suspect it would drop below 100 Watts per channel when running 7 channels, so the 125 Watt 7 channel amp I’ve been considering was a way to buy a non-flagship AVR and still get the minimum power I desire.

Would I like a 200 Watt amp like the Monolith? Sure, but I think even if the power drain on my existing out wasn’t a concern, I don’t really need quite that much power. However, as some have pointed out, the small amount of power I’ve been considering in a 125 Watt amp would probably not be noticeable, so I’m inclined to consider forgoing it in favour of looking at an AVR with more power. The cost of a slightly cheaper AVR and an amp would certainly be higher than something like a Marantz SR8012 or Denon AVR-X6500. But I’m still unsure and probably change my mind tomorrow...