How much power (wpc) is more than enough for most speakers and systems?

[bluegrassphile]

My main priorities for a new amp are superior sonics/outstanding tone/ superb sound...whatever you want to call it. I think you know what I mean. Next in line for me is output power, with enough to effectively cover transient peaks with inaudible distortion, with pretty much any speaker. In my case it would be Harbeth Super HL 5+ 40th Anniversary Model speakers. Just for the record the Harbeths are 6 ohm speakers.

So, given the info above, for you, how much power would meet the minimal requirement for most speakers and systems? Twenty five wpc? Fifty wpc? Eighty wpc? One hundred wpc? One hundred twenty five wpc? One hundred seventy five wpc? Two hundred fifty wpc? More? Keep in mind I'm not talking about any other feature of the amp. Just output power. I realize we're probably not talking about most class A amps as their output levels are usually less than 30 wpc x 2 into 8 ohms. Some class AB amps have a certain amount of class A bias. For example the Luxman 590axii. It is class A up to 30 wpc and then converts to Class AB and outputs approximately 90 wpc x 2 into 8 ohms, according to some magazine tests.

Anyway, how much power is enough for most scenarios? I would think 75 wpc x 2 into 8 ohms would do the job, except, for loud transients. And that's what concerns me most regarding minimum power requirements...higher volume transients, compression and distortion. How much output power is enough to confidently cover them?

[tino27]

I would think that in addition to considering the load of the speakers in question (6 ohms in your case), the efficiency of the speaker would also help to determine how many watts per channel you'd also need in order to have enough headroom for transients. Personally, I have relatively inefficient speakers (83 db/1w/1m), so I choose to go with a nice solid 200wpc amplifier. Obviously, if you're running highly efficient speakers, that might be overkill.

[aKnyght]

i have heard harbeths driven to perfection by mono-block amps putting out 75w rms into 8-ohms / 140w rms into 4-ohms

others here more knowledgeable might be able to correct me and certainly help out better, but it is my understanding that an associated consideration is the ability of an amp and its power distribution to sustain power delivery under "peak demand" circumstances such as loud transients.

[MikeCh]

300 to 500 watts per channel is more than enough for most loudspeakers.

[jdandy]

Anyway, how much power is enough for most scenarios? I would think 75 wpc x 2 into 8 ohms would do the job, except, for loud transients. And that's what concerns me most regarding minimum power requirements...higher volume transients, compression and distortion. How much output power is enough to confidently cover them?

Tom.......For well recorded music that has not been overly compressed during the mastering process it is not uncommon for dynamic peaks to rise 10dB above the average music level. With this in mind you must consider the typical average power you usually use when listening to music, be it 0.5 watts, 1 watt, 3 watts, etc. The Harbeth Super HL 5+ 40th Anniversary speakers have a sensitivity of 86dB/1W/1M. This means that 1 watt will deliver a comfortable average listening level, and that 10dB of dynamic headroom would require the amplifier to deliver slightly less that 10 watts to achieve approximately 96dB sound pressure for clean dynamic range. For every 3dB increase in volume the output power will double. If your typical music listening level with the Harbeth Super HL 5+ speakers is 92dB, then your power requirements will be in the range of 4 watts average, while 10dB peaks that create 102dB of sound pressure will need approximately 34 watts of reserve power. Using this information will allow you to figure out how much amplifier power you require to adequately accommodate your listening requirements.

There is nothing that says you cannot have more power than necessary to support your particular listening habits. It is always better to have more power than not enough, especially for the safety of your midrange and high frequency drivers. In my opinion, 75 watts to 100 watts per channel is a comfortable power level that will allow you to drive nearly any speaker to satisfying volume levels in small to medium sized rooms.

[Dth31]

Agree with what was said above. In addition, the size of the room matters. Bigger rooms need more power.

[bluegrassphile]

i have heard harbeths driven to perfection by mono-block amps putting out 75w rms into 8-ohms / 140w rms into 4-ohms

others here more knowledgeable might be able to correct me and certainly help out better, but it is my understanding that an associated consideration is the ability of an amp and its power distribution to sustain power delivery under "peak demand" circumstances such as loud transients.

Yes, that's what I'm referring to..."peak demand circumstances." Enough power to cover almost any speaker at peak demand without any audible distortion. Speaking in generalities​, how much is enough for most speakers.

[Randy Myers]

As has been stated, there are differences of opinions. For some people they can never have enough power. For others, such as myself, quality is the most important thing.

Dan's explanation above was very good and detailed, and I tend to agree with him. Quality power of 75-100 WPC is more than enough for me.

Obviously, your listening habits do come into play. I am not one that looks to knock the walls down... some people do listen at those levels ...

[bluegrassphile]

300 to 500 watts per channel is more than enough for most loudspeakers.

Yes, Mike, I would certainly agree with that, LOL! So would 1000 watts. But, again speaking in generalities, I'm just wondering what would be the minimum amount of output power you would want to have on tap for just about any speaker? Mike, you know more about this that I'll ever know. That's why I'm asking these questions of experienced and knowledgeable people on this forum such as you. I'm contemplating what the minimum power requirement might be for my Harbeth (6 ohm) speakers at higher volume? Would 125 wpc to 175 wpc x 2 into 6 ohms cover transient peaks with no audible distortion? Maybe it is indeed 300 wpc x 2 into 6 ohms? Most of the time I will not be playing my system at "higher volume levels". But I don't want to hear any distortion when I do. I'm guessing 100+ wpc might cover it. But with my lack of knowledge and experience I just don't know.

[the professor]

One thing to keep in mind. Some power amps handle transients better than others. For example - the 2 box Devialet has a lot of watts (1,000w) but it couldn't keep up with a Accuphase A-70 (60w). This was going into Raidho speakers.

[Al M.]

I would think that in addition to considering the load of the speakers in question (6 ohms in your case), the efficiency of the speaker would also help to determine how many watts per channel you'd also need in order to have enough headroom for transients. Personally, I have relatively inefficient speakers (83 db/1w/1m), so I choose to go with a nice solid 200wpc amplifier. Obviously, if you're running highly efficient speakers, that might be overkill.

I like overkill. My main speakers are 92 dB sensitive 2-way monitors at 8 Ohm impedance, and I use an amp of 100W/ch into 8 Ohms (130 W/ch into 4 Ohms). The monitors can easily be driven with great dynamics by a 15 W/ch amp (have tried it). But with my current amp dynamics are even better.

My JL Audio subs each have an internal amp of 1800 W.

I would agree though with what has been pointed out, that high power does not guarantee great transient performance. Larger amps sometimes are more sluggish, so it all depends. Better judging with your ears rather than a rulebook.

[still-one]

There is more than Watts to be considered when designing a good amp. As Jock notes in Post 10 a relatively low power amp such as the A-70 might do a better job on some speakers than a significantly higher rated one. I found this when I moved from 1.2k's to the original Momentum's. Dan's amps were much better at controlling the difficult to drive MBL 111f'.

Then again there is Relentless.

[bart]

Then again there is Relentless.

Have you ordered yours already Jim?!

[bluegrassphile]

Dan, that was great info and a very helpful post. Sincere thanks to you and everyone else on this thread. It sounds like 75 watts would indeed be adequate and perhaps a comfortable minimum for most situations. That's great to know and very timely since I will be visiting Suncoast Audio soon to decide on an amp to go with my Harbeths. There'll be a LOT of listening to do and I just wanted to make sure I pick something with enough power reserve to drive my speakers at about any volume level without distortion.

I know Suncoast owner, Mike Bovaird, will very competently guide me. But I'm just trying to get a feel for how much output power I'll need. I'm sure I won't be playing my system loud enough to require 300 wpc x 2 into 6 ohms. But I want to have enough of a margin to do the transients justice. OTOH, I don't want so much power that I could accidentally or otherwise fry speakers or an amp. I think the Harbeths are rated at 150 watts. Unless I'm under-powering or over-powering them they should be pretty safe. I might be very occasionally playing them somewhat loud...maybe about 30% to 45% on the volume control, max. Most of the time I'll be operating at maybe 25% to 30%. Anyway, I think you get what I'm talking about. I also think, with the info Dan presented here, and with the amps I'm considering, output power won't even be a factor.

[still-one]

Have you ordered yours already Jim?!

I wish.

[bart]

Dan, that was great info and a very helpful post. Sincere thanks to you and everyone else on this thread. It sounds like 75 watts would indeed be adequate and perhaps a comfortable minimum for most situations. That's great to know and very timely since I will be visiting Suncoast Audio soon to decide on an amp to go with my Harbeths. There'll be a LOT of listening to do and I just wanted to make sure I pick something with enough power reserve to drive my speakers at about any volume level without distortion.

I know Suncoast owner, Mike Bovaird, will very competently guide me. But I'm just trying to get a feel for how much output power I'll need. I'm sure I won't be playing my system loud enough to require 300 wpc x 2 into 6 ohms. But I want to have enough of a margin to do the transients justice. OTOH, I don't want so much power that I could accidentally or otherwise fry speakers or an amp. I think the Harbeths are rated at 150 watts. Unless I'm under-powering or over-powering them they should be pretty safe. I might be very occasionally playing them somewhat loud...maybe about 30% to 45% on the volume control, max. Most of the time I'll be operating at maybe 25% to 30%. Anyway, I think you get what I'm talking about. I also think, with the info Dan presented here, and with the amps I'm considering, output power won't even be a factor.

I've heard your speakers with mono block tube amplifiers of 24W in Class A.
The amps had tight grip on the Harbeths.
I think the example of the Accuphase above tells a lot: not the Watts count, it's the current an amp can produce.

[nicoff]

My experience with amps is that wattage is not always the most appropriate way to judge an amp. I had a B&K amp years ago rated at about 220wpc. But I kept burning fuses and ribbons in my Maggie's. I replaced the amp with a high current amp from another manufacturer but similar wattage and the problem pretty much went away. That said, the interaction between the speaker and the amp may be more important that the wattage.

[BlueFox]

I found with 800/watts per channel I would occasionally have clipping. After upgrading to 1200/watts per channel I no longer have that issue. I did have to install a separate circuit for each amp to prevent the breaker from tripping when both amps were on one circuit. Now it is pure musical bliss.

[Mike]

It depends on the speakers. I’m experimenting with the B&W 800D3’s at the moment and they love power. I put the ARC REF160M’s on them and it sounded beautiful, but the REF6 was at 75 and the sound lacked dynamics. Switch to the Luxman M900u Monos (about 750 watts/ch in bridged mode) or the Gryphon Mephisto and WOW! They come to life.

The Bryston 28SST2’s would be excellent, Hegel H30 Monos, SimAudio monos. Constellation Taurus monos was good too.

Agree with Jock on the Devialet. I had the 400’s and it sounded like 40.


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[mep]

From Harbeth:

https://m.youtube.com/watch?v=bRMR9JZ1m0s

[nicoff]

From Harbeth:

https://m.youtube.com/watch?v=bRMR9JZ1m0s

The bottom line there of that video is that you can never have too much power!

[bluegrassphile]

Thanks for bringing that up, mep. I've watched that video before and it's very interesting and revealing. In fact that video is what got me taking a close look at minimum power requirements for my amp. I would much rather error on the side of excess power than not enough. Those amps in the video are really cooking...~ 500 wpc x 2 into 6 ohms...continuous!! With peaks to 1000 wpc? Yeow!! The one reviewer said people with low powered amps "are missing out". I'm sure those people would disagree or they wouldn't buy the amp in the first place. However...it's my guess if they could be shown what they're missing out on they just might change their minds on output power requirements. Maybe, maybe not.

I'm not sure how this squares with Dan's post. And that's what has me somewhat confused. I can understand how a high end 7 wpc amp might sound wonderful at low volume levels...until you start to push it.

And it might sound great but, according to the video, could sound much greater if it had a LOT more power. Just when I think an amp needs to output 300 wpc to produce clean transients at "elevated" volume levels, I read where 100 wpc x 2 into 8 ohms will adequately cover the transient peaks. I want to reiterate, I know there may be other factors at work here. But remember, I'm speaking in generalities. Keep the posts coming. I'm learning things.

[MikeCh]

I like the 300 to 500 W/pc range just because you never know when you might get jiggy with it.

[jdandy]

Tom.......I have owned my PMC EB1i speakers for 11 years, and in that time I have powered them with an MC275 at 75 watts per channel, a pair of MC275's strapped for mono at 150 watts per channel, a MC300 at 300 watts per channel, a MC352 at 350 watts per channel, a MC452 at 450 watts per channel (currently in the system), a pair of MC501 mono amplifiers at 500 watts per channel, and a pair of MC601's at 600 watts per channel. In all cases with each amplifier the PMC EB1i's sounded wonderful. I typically do not listen above about 95dB peaks, and that's plenty loud in my living room. Each of the amplifiers listed all had sufficient reserve power on tap to produce clean dynamics. The reason I cycled so many different amplifiers through the living room system centered more on curiosity than on need, a desire to experience the different McIntosh amplifiers in that sound system.

Just today I made a deal with my McIntosh dealer to trade my MC452 for a pair of McIntosh MC75 MkII mono tube amplifiers rated at 75 watts per channel. They have a measured output of 90 watts within factory specs. That will provide me with ample power to listen at whatever volume level I find satisfying and still provide sufficient reserve power for peaks. The new MC75 mono tube amps use the same power supply and transformer that McIntosh uses in the MC275 stereo tube amp. That means the power supply is considerably more robust powering the 75 watt mono amp than it is powering both channels of the 75 watts per channel stereo amp. I expect the dynamic capabilities of the MC75 mono tube amps to be superior to the MC275 stereo tube amp. Owner testimonies and reviews have supported the MC75 power supply improvements. The PMC EB1i speakers are 89dB efficient with one watt at one meter. 8 watts output will produce an average music level of 98dB, allowing well over 10dB of dynamic headroom reserve power without clipping the amps. 64 watts of output power will deliver 107dB of sound pressure, far more than my listening criteria requires. I am stepping down from 450 watts per channel currently in use, and from an all time high of 600 watts per channel in the living room system to 75 watts of mono tube power. I expect the sound to be fabulous.

Here is a photo I took one afternoon while listening to my MC601 amplifiers driving the PMC EB1i speakers. I had the meter set to Peak Hold. As you can see, the dynamic headroom of the MC601 is substantial. The McIntosh Power Guard lights weren't even flickering, and the PMC's were rocking the house at concert level. That is not a typical listening scenario for me, but it was an enlightening experience to know the speakers could handle that kind of power and sound good doing it. That's nearly twice the power we saw used in the Harbeth video. The PMC's were producing approximately 120dB of sound pressure. Seriously though, who wants to listen at that volume level without wearing earplugs. Hearing damage takes place at much lower volume levels.





The point I want to make, it's easy to get caught up in the notion that high power amplifiers are an absolute necessity, even for relatively efficient speakers. Sure, there are some difficult to drive speakers with wildly swinging impedance curves and phase relationships that require amplifiers with plenty of reserve current capability, but by and large that is not all that common. 75 watts to 100 watts per channel is a comfortable place to be for many home audio applications. Naturally, there are variables that come into play that revolve around specific applications, listening habits, and personal satisfaction. It's all part of what makes hi-end audio so interesting and fun.

[Mr Peabody]

generally I'm with Mike CH, can't have too much power.

However, Harbeth are typically very easy to drive though not so efficient. Vinnie Rossi drives them with little watts and some of his amps have battery power supplies.

My friend drives various Harbeth with Leben tube integrated. When switching to Totem, then, we have to break out the Naim.

So minimum really depends on several factors as members have brought to the table thus far.

I had 100 watt CJ monoblocks that drove my Dynaudio fine at 86dB but strubbled to bring Revel F52's alive at 88dB. Fed the F52's some current and they began to dance. The CJ made a set of Zu Audio at something like 100dB rock the house.

fun hobby

[Mike]

We have every Harbeth in the store. Every model. I would say 150 watts or more is ideal on average. The 40’s are closer to 200 watts or more ideally. I wouldn’t go less than the Luxman 509x, but to be fair, I haven’t got our SN3 yet. The Pass INT-60 isn’t enough. We have a video posted of the C7’s with the INT-60 at full volume. They need more.

In the $10k ish range, the Hegel 590 man. It has the balls and neutrality and grip a warm speaker needs. And it’s DAC is excellent.

The house favorites with Harbeth are Luxman 509x and Hegel 590.


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[Randy Myers]

If we all needed crazy level power, 400-500-600 wpc; and assuming we all do not have one percenter budgets then we would all own class D amplifiers. Obviously many of us prefer the sound of other types of amplifiers; tubes, class A, class a/b, SET, etc. Therefore for many of us quality is more important then quantity. My 80 wpc amplifier, in my view, is the finest sounding amplifier I have ever own.

[Alpinist]

Tom.......For well recorded music that has not been overly compressed during the mastering process it is not uncommon for dynamic peaks to rise 10dB above the average music level. With this in mind you must consider the typical average power you usually use when listening to music, be it 0.5 watts, 1 watt, 3 watts, etc. The Harbeth Super HL 5+ 40th Anniversary speakers have a sensitivity of 86dB/1W/1M. This means that 1 watt will deliver a comfortable average listening level, and that 10dB of dynamic headroom would require the amplifier to deliver slightly less that 10 watts to achieve approximately 96dB sound pressure for clean dynamic range. For every 3dB increase in volume the output power will double. If your typical music listening level with the Harbeth Super HL 5+ speakers is 92dB, then your power requirements will be in the range of 4 watts average, while 10dB peaks that create 102dB of sound pressure will need approximately 34 watts of reserve power. Using this information will allow you to figure out how much amplifier power you require to adequately accommodate your listening requirements.

There is nothing that says you cannot have more power than necessary to support your particular listening habits. It is always better to have more power than not enough, especially for the safety of your midrange and high frequency drivers. In my opinion, 75 watts to 100 watts per channel is a comfortable power level that will allow you to drive nearly any speaker to satisfying volume levels in small to medium sized rooms.

Excellent post, Dan!

Ken

[bluegrassphile]

It sounds like 100 to 125 wpc x 2 into my 6 ohm Harbeths would be a pretty safe minimum. It also gives me a few more amps to pick from. However, like Mike, I'm anxious to hear the NAIM Supernait 3 that's rated at 80 wpc x 2 into 8 ohms. That's the same power rating as the Supernait 2 and I've only heard glowingly positive comments regarding the Supernait 2. Regarding minimum power requirements, I just don't want to be one of those who are "missing out". But as I mentioned earlier, it doesn't sound like I will be with the amps I have in mind to audition. Thanks again, Dan.

[Shadowfax]

What were those Amps in the video? I thought I saw Pan Sonic, but can't seem to find them in a search. A Band named Pan Sonic comes up.

[Mike]

What were those Amps in the video? I thought I saw Pan Sonic, but can't seem to find them in a search. A Band named Pan Sonic comes up.

Spectral, errr, I mean CH. I wonder if the meters are accurate. The reason I ask is that if you press most manufacturers with meters, they say they are not. Not saying the CH aren’t, but I’m curious.


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[jdandy]

What were those Amps in the video? I thought I saw Pan Sonic, but can't seem to find them in a search. A Band named Pan Sonic comes up.

Brian.......Here is a screen capture from the Harbeth demo video. The amplifiers appear to be CH Precision A1 stereo amps that are being used in bridged mode for 350 watts mono output.

[mep]

The reason I posted this video is because it's a Harbeth video which is trying to demonstrate how much peak power is needed on dynamic music in order to play it cleanly with Harbeth speakers. The lower the sensitivity your speakers have combined with speakers that present a difficult load to drive due to impedance issues, the more power you need.

Personally, if I was shopping for Harbeth speakers and Mike was my dealer, I would certainly listen to his recommendations because Mike has experience with the entire Harbeth line.

[kzhtoo]

Personally, if I was shopping for Harbeth speakers and Mike was my dealer, I would certainly listen to his recommendations because Mike has experience with the entire Harbeth line.

Exactly! Don’t fight off Luxman just because its seemingly lower power rating on paper. It may be THE match for Harbeths as far as SS amps are concerned.

[bluegrassphile]

Luxman is still very much on my radar. Both the 509x and 590axii. Along with Gryphon, Hegel, Simaudio/Moon, Pass, and NAIM. For a tube amp I'll be auditioning VAC. Trying to keep an open mind.

[Shadowfax]

The reason I posted this video is because it's a Harbeth video which is trying to demonstrate how much peak power is needed on dynamic music in order to play it cleanly with Harbeth speakers. The lower the sensitivity your speakers have combined with speakers that present a difficult load to drive due to impedance issues, the more power you need.

Personally, if I was shopping for Harbeth speakers and Mike was my dealer, I would certainly listen to his recommendations because Mike has experience with the entire Harbeth line.

Didn't he say that each reading was a sampling of the Peaks or did I get that wrong. Those numbers are not sustained or continuous, they are nano second spikes I would think. Those speakers would have spontaneously combusted to ash with 500 sustained watts thru that track.

[NorthStar]

I found with 800/watts per channel I would occasionally have clipping. After upgrading to 1200/watts per channel I no longer have that issue. I did have to install a separate circuit for each amp to prevent the breaker from tripping when both amps were on one circuit. Now it is pure musical bliss.

Wow, 1,200 watts should suit a lots of speakers.

I've written a longer post but accidentally it went ...
I know that price (budget) is only important to some.
I've read the full thread, every post, Mep's video, Dan's post on the specs of the Harbeth, etc.

I'd say from 100 to 200 watts (8 Ohms).
E.g.; http://www.bryston.com/products/power_amps/3B-3.html

Good for Organ music, Electronica, Classical Orchestral, ...
...Large rooms, clean power, high level, all that music Jazz.

Bryston have several models; this is only an example of adequate range ... IMO

[kiwi_1282001]

Didn't he say that each reading was a sampling of the Peaks or did I get that wrong. Those numbers are not sustained or continuous, they are nano second spikes I would think. Those speakers would have spontaneously combusted to ash with 500 sustained watts thru that track.

I think the video makes clear the meters are reading instantaneous peaks – not continuous program levels. The CH Precision A1 amplifier is operated here in bridged mode with a max 350 watt per channel output.


During the audio demonstration with dynamic music the power meters regularly read over 500 watt peaks and at times reached up to 750 watts per channel.


The meters used have a hold setting to enable display of instantaneous peak power.


Are the meters accurate was one question I thought about? I don’t have an answer for that. Traditionally and across many fields Swiss engineering has been world class, with a forte of precision engineering recognized worldwide as delivering superior performance and quality. I therefore think the VU meters are more than a worthless gimmick. Further with different music (a string quartet) the peaks were far more subdued, typically below 30 watts and often below 5 watts which feels about right. Finally, Alan Shaw whilst visibly surprised by the instantaneous power reading – it was clearly more than he bargained for – did not go on to challenge the veracity of the result. Indeed in a Harbeth user group thread subsequently referencing the video, Alan admonishes the use of low power amplifiers and states categorically that amplifiers can’t ever be too powerful.

[Mr Peabody]

I don't doubt what you are saying, even Klipsch came out a while back saying their speakers would benefit from higher power amps. Why do you suppose Harbeth has such a huge following with tube amp users? Is it true what they say about Harbeth being easy to drive, or stable, though not so efficient?

We have every Harbeth in the store. Every model. I would say 150 watts or more is ideal on average. The 40’s are closer to 200 watts or more ideally. I wouldn’t go less than the Luxman 509x, but to be fair, I haven’t got our SN3 yet. The Pass INT-60 isn’t enough. We have a video posted of the C7’s with the INT-60 at full volume. They need more.

In the $10k ish range, the Hegel 590 man. It has the balls and neutrality and grip a warm speaker needs. And it’s DAC is excellent.

The house favorites with Harbeth are Luxman 509x and Hegel 590.


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[Mr Peabody]

Randy, there seems to be some error in your perceptions here. Class D is not the only way to buy or achieve high power. Nor, is there any truth that lower power amps necessarily sound better. I personally think the opposite is true as the less hard you drive an amp the further away you are from distortion and other nasties.

With that being said, traditional amps need hardy power supplies and to be able to produce ample current.. This is how Naim is such a power house yet lists not so high watts per channel.

My speakers are 94dB, 6 ohms, my amp is 300x2 into 8 ohms. I love having extra throddle

If we all needed crazy level power, 400-500-600 wpc; and assuming we all do not have one percenter budgets then we would all own class D amplifiers. Obviously many of us prefer the sound of other types of amplifiers; tubes, class A, class a/b, SET, etc. Therefore for many of us quality is more important then quantity. My 80 wpc amplifier, in my view, is the finest sounding amplifier I have ever own.

[Mike]

I don't doubt what you are saying, even Klipsch came out a while back saying their speakers would benefit from higher power amps. Why do you suppose Harbeth has such a huge following with tube amp users? Is it true what they say about Harbeth being easy to drive, or stable, though not so efficient?

They are easy to drive from an impedance standpoint. No wild swings or crazy stuff like when you look at the measurement called EPDR (equivalent peak dissipation resistance). Speakers like the Wilson Audio Alexia 2 have a 1.3 EPDR. Wilson DAW are 1.1 ohm. Focal Sopra have EPDR of 1.1 ohm, Magico S3 0.5 ohm, Sonus Faber Amati is 1.7 ohm, Wilson Sabrina 1.1 Ohm, Martin Logan Neolithic 0.4 ohm, Focal Grande Utopia 1.1 ohm, Wilson Audio Alexx 0.7 ohm, Martin Logan Renaissance 0.3 ohm . The 800D3 are 1.3 ohm and easier to drive than some Wilson’s, Magicos, Martin Logan’s, Focal and the B&W 802D3 and harder than Sonus Faber. I don’t have the exact EPDR measurement for the Harbeth’s, but in stereophiles review, they didn’t dip below 4ohms.

That being said, they like watts. The 40’s especially. 250+ IMO. Girly tube amps need not apply.


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[mep]

Didn't he say that each reading was a sampling of the Peaks or did I get that wrong. Those numbers are not sustained or continuous, they are nano second spikes I would think. Those speakers would have spontaneously combusted to ash with 500 sustained watts thru that track.

You are correct. That is peak power readings you are seeing that rise and fall very quickly.

[Mr Peabody]

Yes sir, I know any speaker with efficiency in the mid 80's would need a big amp for my listening habits, LOL

They are easy to drive from an impedance standpoint. No wild swings or crazy stuff like when you look at the measurement called EPDR (equivalent peak dissipation resistance). Speakers like the Wilson Audio Alexia 2 have a 1.3 EPDR. Wilson DAW are 1.1 ohm. Focal Sopra have EPDR of 1.1 ohm, Magico S3 0.5 ohm, Sonus Faber Amati is 1.7 ohm, Wilson Sabrina 1.1 Ohm, Martin Logan Neolithic 0.4 ohm, Focal Grande Utopia 1.1 ohm, Wilson Audio Alexx 0.7 ohm, Martin Logan Renaissance 0.3 ohm . The 800D3 are 1.3 ohm and easier to drive than some Wilson’s, Magicos, Martin Logan’s, Focal and the B&W 802D3 and harder than Sonus Faber. I don’t have the exact EPDR measurement for the Harbeth’s, but in stereophiles review, they didn’t dip below 4ohms.

That being said, they like watts. The 40’s especially. 250+ IMO. Girly tube amps need not apply.


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[jdandy]

Yesterday, just for fun, I spent several hours playing music on the living room sound system while paying close attention to the McIntosh MC452 meters set to peak hold. I was interested in discovering my typical amplifier demands at an enjoyable volume level, one that you would have to turn down a bit to have a comfortable conversation. The average peak power driving the 4 ohm PMC EB1i speakers with an efficiency of 89dB/1W/1M was just under 10 watts, and often around 4.5 watts. If I turned up the volume where peaks averaged 45 watts, the living room was rocking loud. 95% of my listening with the living room system falls into the category of less than 10 watts peak, and often lower. With the MC452 power amplifier (450 watts continuous per channel) I have a substantial amount of unused power on tap that is unnecessary.

[Randy Myers]

Yesterday, just for fun, I spent several hours playing music on the living room sound system while paying close attention to the McIntosh MC452 meters set to peak hold. I was interested in discovering my typical amplifier demands at an enjoyable volume level, one that you would have to turn down a bit to have a comfortable conversation. The average peak power driving the 4 ohm PMC EB1i speakers with an efficiency of 89dB/1W/1M was just under 10 watts, and often around 4.5 watts. If I turned up the volume where peaks averaged 45 watts, the living room was rocking loud. 95% of my listening with the living room system falls into the category of less than 10 watts peak, and often lower. With the MC452 power amplifier (450 watts continuous per channel) I have a substantial amount of unused power on tap that is unnecessary.

That sounds about right Dan. Even though I do not have the meters to prove it, I know that the T+A, at 80 WPC, is never ever being stressed in even what I consider loud listening sessions...

When do you get the 75 monos? I bet they will work beautifully for you!

[jdandy]

That sounds about right Dan. Even though I do not have the meters to prove it, I know that the T+A, at 80 WPC, is never ever being stressed in even what I consider loud listening sessions...

When do you get the 75 monos? I bet they will work beautifully for you!

Randy.......My McIntosh dealer is delivering a pair of MC75 amplifiers this coming Tuesday afternoon. I am excited to get them into the living room system.

[Randy Myers]

Awesome Dan, and gratz! I am sure you will enjoy the performance of those monoblocks!

[bart]

Randy.......My McIntosh dealer is delivering a pair of MC75 amplifiers this coming Tuesday afternoon. I am excited to get them into the living room system.

Dan, a comparison with your current mono blocks in the works?

[jdandy]

Dan, a comparison with your current mono blocks in the works?

Bart.......I will eventually make the comparison to the MC2301's in the studio system. Initially the MC75 amplifiers are being installed in the living room system to replace the MC452 that I traded to the dealer. I want to get some hours on the amps in the living room system and become familiar with their performance first. I have a full set of my preferred tubes (2-Gold Lion ECC83/12AX7, 4-Siemens ECC801S/12AT7, 4-Gold Lion KT88) waiting for the amps to arrive, plus I have two Wireworld Silver Electra power cords and two Furutech Flux 50's that will power the amps from a dedicated 20 amp circuit with a PS Audio Soloist Supreme SE outlet. Things are looking good for the Tuesday afternoon delivery. These MC75 amps are going to sound amazing.

[Mr Peabody]

You really have to wonder about the accuracy of the meters. That scenario just don't seem to hold up in real world listening.

My Dyn's were 6 ohm and sensitivity in the mid 80's. I bought one 60 watt stereo CJ tube amp and felt I needed more power. I eventually found another of the same amp used and had both converted to mono, at around 100 watts I was alright. Then when switching to a more efficient Revel speaker the amps just wasn't doing the trick. Maybe the F52's weren't as stable, maybe due to twice as many drivers, who knoews, but, facts are facts. A higher power solid state amp brought the F52's to life. That would be the Pass X250.

If we would only use 10 watts or less leads me to questions, like why bother building the massive power amps, why bias an amp into 20 watts class A or so if the amp would never leave Class A, on and on.

I suspect some of it is dynamics that would require power reserves and that decibels are in reality logrithmic. That still wouldn't fully account for only use 10 watts and less.

Yesterday, just for fun, I spent several hours playing music on the living room sound system while paying close attention to the McIntosh MC452 meters set to peak hold. I was interested in discovering my typical amplifier demands at an enjoyable volume level, one that you would have to turn down a bit to have a comfortable conversation. The average peak power driving the 4 ohm PMC EB1i speakers with an efficiency of 89dB/1W/1M was just under 10 watts, and often around 4.5 watts. If I turned up the volume where peaks averaged 45 watts, the living room was rocking loud. 95% of my listening with the living room system falls into the category of less than 10 watts peak, and often lower. With the MC452 power amplifier (450 watts continuous per channel) I have a substantial amount of unused power on tap that is unnecessary.