Emotiva amp for B&W Nautilus 801s

[invaderzim]

I have a pair of B&W Nautilus 801s that I got about 20 years ago. I use these for music and also for movies/TV. They are currently being driven by a Nakamichi PA-7 (200WPC Threshold design licensed by Nakamichi) that I've owned since the 1980s and dug out of the closet after the Sony STR-DA9000ES 200WPC class-D digital receiver/amp died maybe 5 years ago. The preamp/preprocessor is a Marantz AV8801 that I bought intending to assemble a 7.1 system but I never got around to it until now.

I'm thinking the Nakamichi is now on its last legs and I'm in the process of specifying a 7.1 and eventually an Atmos system, but the first step is to replace the amp. The dealer I'm working with recommended either an ARCAM PA240 ($2200) or Parasound A21+ ($3000).  I can't find much about the ARCAM which is a bit odd as they have a great reputation, but the Parasound seems like a safe, hassle-free choice.

My purpose here: I'm thinking of trying out Emotiva amps for the 801s because if it works, it'll be much less expensive than either solution and might get me to where I want to be at a much lower cost. 

It looks like either 2 of the XPA HC1 monoblocks, or the XPA-DR2 might do the trick.  However, the B&W Nautilus 801s go down to 3 ohms and I'm worried about stability.  Is that a problem?

I also don't see anything about current output in the specs.  My Nakamichi PA-7 claims 30amps of peak current/channel and the Parasound claims 60 amps/channel (ARCAM is similar).  Does that matter?

Also, the amp lives in an upstairs equipment room so the 12 gauge speaker wire run (two pairs for each speaker so I could potentially biamp but for now, just biwired) to each speaker is about 50 feet.  Is damping factor important?  Parasound claims >1100.

If not, what's a better starting point?  Monoblocks with less power, or the XPA-DR2 with more power but a single power supply and differential amps? 

I will be adding a center channel but it's not going to be huge (I'm looking at GoldenEar for center and surrounds), so if this works out, I'd be coming back for a multi-channel amp to drive the rest of the speakers.   Or maybe even if I need something else for the B&Ws..

Thanks in advance for the advice.

[Boomzilla]

With 50 feet of wire, damping factor IS important. Paul McGowan (PS-Audio) recommends long XLR interconnects and shorter speaker wires. In your situation, I think that would be a good recommendation. Amps? Were I you, yes, I'd go with mono blocks. Some contenders (in my order of preference):

McIntosh MC2KW
Van Alstine DVA-850
Odyssey Stratos Mono
Krell Solo 575 XD

[ttocs]

3 Ohms is nothing to worry about. Non-issue.

The 50 foot speaker cable run? Issue.

The speaker wire is the limitation in this exercise. The longer the speaker wire, the less I'd be concerned about expecting to hear nuances of exponentially more expensive amps. Do what Boom recommends.

[rogersch]

Or assemble your own mono block amps....
www.diyclassd.com/product/nc400-mono-kit-complete-kit/24
They can definitly handle your speakers....

[pedrocols]

Sept 9, 2020 20:16:48 GMT -5 rogersch said:

Or assemble your own mono block amps....
www.diyclassd.com/product/nc400-mono-kit-complete-kit/24
They can definitly handle your speakers....

I forgot about those. It seems the honeymoon phase about those amps faded away.

[invaderzim]

Whoah, that McIntosh MC2KW is $85,000 each and the Krells are $22,000/pair! Can't do that.

Balanced XLR interconnects would have been a good idea when I did the wiring back in 2017 but then I'm still faced with putting the amp in the family room and the point was to get all the equipment in a common location. Because I had to open a wall in a room with a 16 foot ceiling to get the cables down to the 1st floor, I did put in a conduit for HDMI cables since those standards evolve regularly -- so I could still switch to this scheme and add the wires if they're not too thick. I think once I get the amp I'll try it next to the speakers and consider the balanced interconnect idea along with the 12v trigger if it makes enough of a difference. So thanks for that suggestion.

Regarding digital amps, D-Sonic is something else I was considering but unlike Emotiva, they have a restocking fee--I guess that lessens the guilt slightly if a return is required. It would still be nice not to have a space heater in my office.

Anyway, I didn't see any recommendation for the Emotiva amps for my particular situation. So it'll probably be the Parasound but I might be back for the multi-channel surrounds when the time comes.

[leonski]

Sept 9, 2020 15:54:41 GMT -5 ttocs said:

3 Ohms is nothing to worry about. Non-issue.

The 50 foot speaker cable run? Issue.

The speaker wire is the limitation in this exercise. The longer the speaker wire, the less I'd be concerned about expecting to hear nuances of exponentially more expensive amps. Do what Boom recommends.

While 3 ohms isn't 'an issue', B&W speakers are typically NOT the most amplifier friendly load.    I have no detail on the 801s, but if you look, Stereophile may test them and publish real measurements.....

Real work DF is Aways much lower than 'advertised'.     For long runs, I would recommend going 1 gauge larger than you would normally.      And yes, longer balanced runs and shorter speaker wire runs IF Possible.   

[leonski]

An amplifier MAY claim some ridiculous high number for DF, but that is a Fiction of the Advertising department.
Real World DF is ALWAYs lower, sometimes a lot.
And with tube amps and 'Big Box' (old school) speakers, pretty much a Non-Issue, anyway.
But for modern speakers? Is there Really Any benefit to a DF of over say......50.....with all elements in the circuit?

When I made power semiconductors, one measureable was the Rdon.....Resistance of the Device in the ON state. Lower was better since
it produced less wasted energy, which ALwAYS expresses itself as HEAT.

[garbulky]

I would recommend a pair of used xpa-1 gen 2 amps.

[Deleted]

Sept 9, 2020 15:40:06 GMT -5 Boomzilla said:

With 50 feet of wire, damping factor IS important. Paul McGowan (PS-Audio) recommends long XLR interconnects and shorter speaker wires. In your situation, I think that would be a good recommendation. Amps? Were I you, yes, I'd go with mono blocks. Some contenders (in my order of preference):

McIntosh MC2KW
Van Alstine DVA-850
Odyssey Stratos Mono
Krell Solo 575 XD

I was looking at the specs of the Krell amp as your recommendation. 22 amps output, really? That's all?

[leonski]

Sure, Shiei, It WILL do that for about a FemtoSecond at maybe 0.1 volts. Hardly useful.

Note they don't say HOW this wacky number was arrived at. Think you speaker can handle it?

Than PLUG ONE INTO THE WALL.....Hopefully you have a 20 amp circuit. That should be a reasonable test.

20 amps at 115vac, or maybe it's gonna sag to 80vac or whatever, all at a bass-heavy 60hz. That's only 1600 watts.....

[metaldaze]

Sept 9, 2020 14:45:25 GMT -5 invaderzim said:

I have a pair of B&W Nautilus 801s that I got about 20 years ago. I use these for music and also for movies/TV. They are currently being driven by a Nakamichi PA-7 (200WPC Threshold design licensed by Nakamichi) that I've owned since the 1980s and dug out of the closet after the Sony STR-DA9000ES 200WPC class-D digital receiver/amp died maybe 5 years ago. The preamp/preprocessor is a Marantz AV8801 that I bought intending to assemble a 7.1 system but I never got around to it until now.

I'm thinking the Nakamichi is now on its last legs and I'm in the process of specifying a 7.1 and eventually an Atmos system, but the first step is to replace the amp. The dealer I'm working with recommended either an ARCAM PA240 ($2200) or Parasound A21+ ($3000).  I can't find much about the ARCAM which is a bit odd as they have a great reputation, but the Parasound seems like a safe, hassle-free choice.

My purpose here: I'm thinking of trying out Emotiva amps for the 801s because if it works, it'll be much less expensive than either solution and might get me to where I want to be at a much lower cost. 

It looks like either 2 of the XPA HC1 monoblocks, or the XPA-DR2 might do the trick.  However, the B&W Nautilus 801s go down to 3 ohms and I'm worried about stability.  Is that a problem?

I also don't see anything about current output in the specs.  My Nakamichi PA-7 claims 30amps of peak current/channel and the Parasound claims 60 amps/channel (ARCAM is similar).  Does that matter?

Also, the amp lives in an upstairs equipment room so the 12 gauge speaker wire run (two pairs for each speaker so I could potentially biamp but for now, just biwired) to each speaker is about 50 feet.  Is damping factor important?  Parasound claims >1100.

If not, what's a better starting point?  Monoblocks with less power, or the XPA-DR2 with more power but a single power supply and differential amps? 

I will be adding a center channel but it's not going to be huge (I'm looking at GoldenEar for center and surrounds), so if this works out, I'd be coming back for a multi-channel amp to drive the rest of the speakers.   Or maybe even if I need something else for the B&Ws..

Thanks in advance for the advice.

I currently have an A21+ from Parasond. I've had it for around 3 months. I've been very happy with it coming from an XPA-4 Gen 3. I still have that amp, but use it for the surrounds and occasionally the center when I want to.

My mains are Ohm Acoustics Model H (all 3 front channels) or The model 'I'. I have the "I's hooked up now that they're updated from Ohm and the room is properly treated. These are large floor standing speakers capable of handling lots of power and realistic levels without breakup. Also bi-amp capable. The A21+ handles them very well and their claim of 60amps peak current per channel I believe is congruent with it's real world capability. A very sweet sound backed with 10watts class A per channel and tested by stereophile into 1.5 ohm stability. It does get noticeably warmer than the Emotiva. Just the topology, so I use an aircom S9 on top of the parasound and it works great.

As others have said the damping factor will be a point of contention using speaker wire runs that long. A longer XLR interconnect and short speaker wire is preferable if at all possible. Otherwise, I agree use 10 AWG to help offset the increased impedance of the longer speaker wire run.

My knee jerk reaction with strictly speaking with the Emotiva amps is go for the more powerful DR series. But With the lower impedance dips of the speaker and such a long speaker wire run. Makes me wonder if the totally differential circuitry of the DR amps may run into protection. Sending Emotiva an email to ask directly about this if you're interested in testing the amp will probably be best.

Cheers

[leonski]

I have kind of an 'aside' question, if I may?

Why does the OP think his Nakamichi is 'on its last legs'? Sure, it's and older piece, but if it is one of the Pass Stasis designs? Maybe just a PS recap will do it?

And NO, peak current is a red herring specification. And as it turns out? NOBODY knows how it is measured including measured voltage out at that current and the TIME duration of such a pulse......

[Deleted]

Sept 14, 2020 13:10:33 GMT -5 metaldaze said:

Sept 9, 2020 14:45:25 GMT -5 invaderzim said:

I have a pair of B&W Nautilus 801s that I got about 20 years ago. I use these for music and also for movies/TV. They are currently being driven by a Nakamichi PA-7 (200WPC Threshold design licensed by Nakamichi) that I've owned since the 1980s and dug out of the closet after the Sony STR-DA9000ES 200WPC class-D digital receiver/amp died maybe 5 years ago. The preamp/preprocessor is a Marantz AV8801 that I bought intending to assemble a 7.1 system but I never got around to it until now.

I'm thinking the Nakamichi is now on its last legs and I'm in the process of specifying a 7.1 and eventually an Atmos system, but the first step is to replace the amp. The dealer I'm working with recommended either an ARCAM PA240 ($2200) or Parasound A21+ ($3000).  I can't find much about the ARCAM which is a bit odd as they have a great reputation, but the Parasound seems like a safe, hassle-free choice.

My purpose here: I'm thinking of trying out Emotiva amps for the 801s because if it works, it'll be much less expensive than either solution and might get me to where I want to be at a much lower cost. 

It looks like either 2 of the XPA HC1 monoblocks, or the XPA-DR2 might do the trick.  However, the B&W Nautilus 801s go down to 3 ohms and I'm worried about stability.  Is that a problem?

I also don't see anything about current output in the specs.  My Nakamichi PA-7 claims 30amps of peak current/channel and the Parasound claims 60 amps/channel (ARCAM is similar).  Does that matter?

Also, the amp lives in an upstairs equipment room so the 12 gauge speaker wire run (two pairs for each speaker so I could potentially biamp but for now, just biwired) to each speaker is about 50 feet.  Is damping factor important?  Parasound claims >1100.

If not, what's a better starting point?  Monoblocks with less power, or the XPA-DR2 with more power but a single power supply and differential amps? 

I will be adding a center channel but it's not going to be huge (I'm looking at GoldenEar for center and surrounds), so if this works out, I'd be coming back for a multi-channel amp to drive the rest of the speakers.   Or maybe even if I need something else for the B&Ws..

Thanks in advance for the advice.

I currently have an A21+ from Parasond. I've had it for around 3 months. I've been very happy with it coming from an XPA-4 Gen 3. I still have that amp, but use it for the surrounds and occasionally the center when I want to.

My mains are Ohm Acoustics Model H (all 3 front channels) or The model 'I'. I have the "I's hooked up now that they're updated from Ohm and the room is properly treated. These are large floor standing speakers capable of handling lots of power and realistic levels without breakup. Also bi-amp capable. The A21+ handles them very well and their claim of 60amps peak current per channel I believe is congruent with it's real world capability. A very sweet sound backed with 10watts class A per channel and tested by stereophile into 1.5 ohm stability. It does get noticeably warmer than the Emotiva. Just the topology, so I use an aircom S9 on top of the parasound and it works great.

As others have said the damping factor will be a point of contention using speaker wire runs that long. A longer XLR interconnect and short speaker wire is preferable if at all possible. Otherwise, I agree use 10 AWG to help offset the increased impedance of the longer speaker wire run.

My knee jerk reaction with strictly speaking with the Emotiva amps is go for the more powerful DR series. But With the lower impedance dips of the speaker and such a long speaker wire run. Makes me wonder if the totally differential circuitry of the DR amps may run into protection. Sending Emotiva an email to ask directly about this if you're interested in testing the amp will probably be best.

Cheers

I came from a DR3 Emotiva to a Parasound A31 and hands down no comparison I love the Parasound. Like your A21+ mine produces 60+ amps per channel. And regarding the 10watts class A power rating of the Parasound another person on this board contacted Parasound and they said it is gradual and not an instant "switch" from class A to class AB. The gradual transition is more like 14-18watts. 

[Deleted]

Sept 14, 2020 12:43:13 GMT -5 leonski said:

Sure, Shiei, It WILL do that for about a FemtoSecond at maybe 0.1 volts. Hardly useful.

Note they don't say HOW this wacky number was arrived at. Think you speaker can handle it?

Than PLUG ONE INTO THE WALL.....Hopefully you have a 20 amp circuit. That should be a reasonable test.

20 amps at 115vac, or maybe it's gonna sag to 80vac or whatever, all at a bass-heavy 60hz. That's only 1600 watts.....

I'll take a high current output amp w/ huge transformer any day. I couldn't care less how much power consumption [inefficiency] and heat the dang thing produces. Power is cheap where I live. 

[metaldaze]

[/quote]I came from a DR3 Emotiva to a Parasound A31 and hands down no comparison I love the Parasound. Like your A21+ mine produces 60+ amps per channel. And regarding the 10watts class A power rating of the Parasound another person on this board contacted Parasound and they said it is gradual and not an instant "switch" from class A to class AB. The gradual transition is more like 14-18watts. [/quote]


+1. That may or may not have been me? I did speak with Phil a couple of times on the phone. Super nice guy and very easy to talk to. And yeah he did mention that the slide into A/B was gradual. And " the magic " was not knowing or hearing rather, when that transition takes place.

leonski the current ratings may be a bit of a red herring specification. As is a damping factor over 20. As stated by John Curl himself. But having that DF I believe helps control the output better and relates to the very low IMD numbers the amp produces. I can't measure Amperes by listening. But I do know there was an instant and noticeable difference in the bass on both my sealed and ported speakers. Its more filled in, extended, and well controlled. I figured from there the current capability was responsible.

[invaderzim]

Sept 14, 2020 14:10:47 GMT -5 leonski said:

I have kind of an 'aside' question, if I may?

Why does the OP think his Nakamichi is 'on its last legs'? Sure, it's and older piece, but if it is one of the Pass Stasis designs? Maybe just a PS recap will do it?

And NO, peak current is a red herring specification. And as it turns out? NOBODY knows how it is measured including measured voltage out at that current and the TIME duration of such a pulse......

Yes, I'm told it's a Nelson Pass Threshold designed amp, licensed to Nakamichi.  It weighs 60 lbs and is beautifully made.

Actually, I'm planning on turning the PA-7 (and the companion pieces in the closet) over to a local shop to be checked out and recapped, once I have a replacement 2-channel amp.  Already discussed it with the owner and he's capable.  The amp was only serviced once -- a couple of years after I bought it when Nakamichi announced a modification to increase the power -- can't remember exactly, but it was something about removing current limiting or overload protection.  That would have been in the mid-1980s. 

It's been a great amp and drove my first pair of speakers, Apogee Duetta Signatures, like a dream for 8 or 9  years. I still miss those speakers but they needed far too much space (6 feet from the rear wall) and when we switched to a combo A/V and music system, the 801s made more sense and I got a great deal as the diamonds were coming out. The Apogee buyer drove his minivan overnight from Atlanta to Texas overnight and couldn't have been more excited to get them. 

The PA-7 still sounds great, but seems to me that there was more bass and even better imaging a couple of years ago. Still, the B&Ws just disappear and voices are rock-steady in the middle, so I never had a desire for a center channel for dialog until recently.  But maybe it's my ears that are getting old, not the amp.

I figured I'd get a 2-channel amp for the B&Ws, service the PA-7 and temporarily use 1/2 of it to drtive center channel until I figure out what kind of multi-channel surround system I want and what kind of amplification it'll need.  I'm thinking I'll wind up with a 7.0.4 system (the B&Ws can rattle the house when Godzilla comes stomping by, so no sub) but that's a lot of amplifiers, which is where Emotiva has a leg up.

Since I have all three Nakamichi components -- CA-7A preamp and ST-7 tuner (not used in years and also due for service) along with the PA-7 amp -- when I'm ready to part with them, I figured I'd sell the set to someone looking for "classic" stuff and defray the cost of hte new system. I had a Pioneer SX-1250 receiver in the closet that I got in the 1970s, put it up for sale about 10 years ago, and was amazed at how many people wanted it.  Sold it to a local building a 1970s "man cave".

I figured the peak current wasn't really a thing, but it might still say something about the power supply's capabilities.

[invaderzim]

Sept 14, 2020 13:10:33 GMT -5 metaldaze said:

I currently have an A21+ from Parasond. I've had it for around 3 months. I've been very happy with it coming from an XPA-4 Gen 3. I still have that amp, but use it for the surrounds and occasionally the center when I want to.

My mains are Ohm Acoustics Model H (all 3 front channels) or The model 'I'. I have the "I's hooked up now that they're updated from Ohm and the room is properly treated. These are large floor standing speakers capable of handling lots of power and realistic levels without breakup. Also bi-amp capable. The A21+ handles them very well and their claim of 60amps peak current per channel I believe is congruent with it's real world capability. A very sweet sound backed with 10watts class A per channel and tested by stereophile into 1.5 ohm stability. It does get noticeably warmer than the Emotiva. Just the topology, so I use an aircom S9 on top of the parasound and it works great.

As others have said the damping factor will be a point of contention using speaker wire runs that long. A longer XLR interconnect and short speaker wire is preferable if at all possible. Otherwise, I agree use 10 AWG to help offset the increased impedance of the longer speaker wire run.

My knee jerk reaction with strictly speaking with the Emotiva amps is go for the more powerful DR series. But With the lower impedance dips of the speaker and such a long speaker wire run. Makes me wonder if the totally differential circuitry of the DR amps may run into protection. Sending Emotiva an email to ask directly about this if you're interested in testing the amp will probably be best.

Cheers

Thanks!  And thanks for the tip about the Aircom.  That's something that I think I can use.  The 12 gauge in-wall-rated speaker wire is already installed and I'd have to open the wall to change it.  I do have 6 pairs of wires -- 2 for left, 2 for right, 2 for a center I'm not using.  The B&Ws are currently bi-wired at the amp (could be biamped).  So maybe that gets me a little better than 12 gauge.  And the Nakamichi PA-7 gets really hot, so I'm used to that.  (One reason I'm concerned about its longevity after 35 years -- the insides are probably baked by now). 

I did see an Emotiva statement saying "don't go below 4 ohms" and that might have been with the differential amps. 

My lovely wife is telling me to just get the A21+ despite the price. I think she's tired of the hemming-and-hawing and wants it over with, so I can move onto the surround sound.

[metaldaze]

Sept 14, 2020 20:54:14 GMT -5 invaderzim said:

Sept 14, 2020 13:10:33 GMT -5 metaldaze said:

I currently have an A21+ from Parasond. I've had it for around 3 months. I've been very happy with it coming from an XPA-4 Gen 3. I still have that amp, but use it for the surrounds and occasionally the center when I want to.

My mains are Ohm Acoustics Model H (all 3 front channels) or The model 'I'. I have the "I's hooked up now that they're updated from Ohm and the room is properly treated. These are large floor standing speakers capable of handling lots of power and realistic levels without breakup. Also bi-amp capable. The A21+ handles them very well and their claim of 60amps peak current per channel I believe is congruent with it's real world capability. A very sweet sound backed with 10watts class A per channel and tested by stereophile into 1.5 ohm stability. It does get noticeably warmer than the Emotiva. Just the topology, so I use an aircom S9 on top of the parasound and it works great.

As others have said the damping factor will be a point of contention using speaker wire runs that long. A longer XLR interconnect and short speaker wire is preferable if at all possible. Otherwise, I agree use 10 AWG to help offset the increased impedance of the longer speaker wire run.

My knee jerk reaction with strictly speaking with the Emotiva amps is go for the more powerful DR series. But With the lower impedance dips of the speaker and such a long speaker wire run. Makes me wonder if the totally differential circuitry of the DR amps may run into protection. Sending Emotiva an email to ask directly about this if you're interested in testing the amp will probably be best.

Cheers

Thanks!  And thanks for the tip about the Aircom.  That's something that I think I can use.  The 12 gauge in-wall-rated speaker wire is already installed and I'd have to open the wall to change it.  I do have 6 pairs of wires -- 2 for left, 2 for right, 2 for a center I'm not using.  The B&Ws are currently bi-wired at the amp (could be biamped).  So maybe that gets me a little better than 12 gauge.  And the Nakamichi PA-7 gets really hot, so I'm used to that.  (One reason I'm concerned about its longevity after 35 years -- the insides are probably baked by now). 

I did see an Emotiva statement saying "don't go below 4 ohms" and that might have been with the differential amps. 

My lovely wife is telling me to just get the A21+ despite the price. I think she's tired of the hemming-and-hawing and wants it over with, so I can move onto the surround sound.

No problem. Glad to hear the WAF is on your side! I had my XPA as my first large outboard amplifier for 3 1/2 years until I finally took the leap after doing my own hemming-and-hawing for quite some time as well. Nothing against Emotiva, but I do wish I had just did that in the first place and perhaps a little more research on my own behalf.  A home trial is always great if you can audition the amp. I got my from AudioAdvisor so I would have had to ship it back if I didn't care for it. But I couldn't be happier with it. It reminds me a bit of my Dad's big Onkyo reciever from the late 70's.. but cleaner and better in every way. Your mileage may vary but I do not think you would be disappointed with that amp. 

And yes the aircom is a nice unit. Its all metal, quite, moves a lot of air and auto senses fan speed according to temperature.  A nice piece of kit for 79 bucks. 

Cheers

[leonski]

Sept 14, 2020 14:23:16 GMT -5 @shimei said:

Sept 14, 2020 12:43:13 GMT -5 leonski said:

Sure, Shiei, It WILL do that for about a FemtoSecond at maybe 0.1 volts. Hardly useful.

Note they don't say HOW this wacky number was arrived at. Think you speaker can handle it?

Than PLUG ONE INTO THE WALL.....Hopefully you have a 20 amp circuit. That should be a reasonable test.

20 amps at 115vac, or maybe it's gonna sag to 80vac or whatever, all at a bass-heavy 60hz. That's only 1600 watts.....

I'll take a high current output amp w/ huge transformer any day. I couldn't care less how much power consumption [inefficiency] and heat the dang thing produces. Power is cheap where I live. 

Sure, A BIG linear PS is pretty darn good and hard to beat.      Should have the ability to provide for better dynamic headroom than a Switcher, any day of the week, too.

But keep one major thing in mind.    This efficiency thing is a RED HERRING.   Given that speakers are so AWFUL at turning power / watts into SOUND we hear, (3% or 4%) would be a high number, than multiply by the efficiency of the amplifier, which at normal levels, even for a 'D'' amp with a SMPS, won't normally exceed maybe 50% or so?    You can see that the vast major of power input to your system goes to HEAT.  Good in cold climates or winter here in SoCal, but in SUMMER?    A drag on the A/C.      Given also that at the highest levels your 'D' amp might be (using MUSIC) maybe 80% from plug to output......you're still turnng a LOT of power into heat.  

ONE possible and constructive approach is to find a very high sensitivity speaker that you REALLY LIKE.      That way?  Even though you'll still turn a lot of electricity into heat, you will not need a super-high power amp.   Some people swear by 5 or 10 watts while others have very satisfying systems with maybe 35, like an old Dynaco Stereo 70 (modernized, maybe?)     At that point?   SCREW the heat and get a single ended Class-'A' amp' and be done......