This is how Nelson listens to music on his 95dB speakers, and it is virtually identical to what I have observed also.
"Perhaps you want to know something about how much power you want to buy? Here's
something that I call the One Watt Window.
It's a picture of some music on an oscilloscope screen, and you can see that there's a line that wiggles up and down, that's the voltage representing the music over a small period of time. I have set the voltage scale so that this is the output voltage that an amplifier with a 1watt rating can fill from top to bottom. Any waveform that stays in this window can be done by a 1 watt amplifier, and you see that this music is safely inside that range.
I made this image yesterday while I was listening to music on my Tannoy loudspeakers. The sound was at a normal listening level, and the group was Massive Attack. The spike you see is percussion. The Tannoys have about 95 dB/watt sensitivity,
I'm saying that you might never have imagined that you could be happy with a 1 watt amplifier." Nelson Pass
"Perhaps you want to know something about how much power you want to buy? Here's
something that I call the One Watt Window.
It's a picture of some music on an oscilloscope screen, and you can see that there's a line that wiggles up and down, that's the voltage representing the music over a small period of time. I have set the voltage scale so that this is the output voltage that an amplifier with a 1watt rating can fill from top to bottom. Any waveform that stays in this window can be done by a 1 watt amplifier, and you see that this music is safely inside that range.
I made this image yesterday while I was listening to music on my Tannoy loudspeakers. The sound was at a normal listening level, and the group was Massive Attack. The spike you see is percussion. The Tannoys have about 95 dB/watt sensitivity,
I'm saying that you might never have imagined that you could be happy with a 1 watt amplifier." Nelson Pass
re-read first post
btw. in my workshop I have Papa's Koan (F4) driven in that manner that I have under 1W/16R , on spks having circa 93db/W
so , current is not a problem and I'm finding sometimes that I wish to have little more voltage sent to amp/spks
but I'm lazy and in minimalistic mood
in living room I have pretty much similar spks/drivers to Papa's said reference and I agree that 1W on them is mucho
however , playing and staying in fleawatt field is matter of choice ........... but personal choice (based on experience) , not result of blindly taken advice from some Dodo on Dodoforum
btw. in my workshop I have Papa's Koan (F4) driven in that manner that I have under 1W/16R , on spks having circa 93db/W
so , current is not a problem and I'm finding sometimes that I wish to have little more voltage sent to amp/spks
but I'm lazy and in minimalistic mood
in living room I have pretty much similar spks/drivers to Papa's said reference and I agree that 1W on them is mucho
however , playing and staying in fleawatt field is matter of choice ........... but personal choice (based on experience) , not result of blindly taken advice from some Dodo on Dodoforum
5 Watts isn't exactly fleawatt on 95dB speakers.
Yes more would allow more overhead to cover every scenario, but I think 90% of the time he will be well below 2Watts.
He also said he will be purchasing an F6 or Aleph J. The ACA is just a way to build something quickly and be listening to music ASAP.
I'm sure there will be plenty of people (myself included) willing to buy the ACA if he decides he wants to sell it later on.
Yes more would allow more overhead to cover every scenario, but I think 90% of the time he will be well below 2Watts.
He also said he will be purchasing an F6 or Aleph J. The ACA is just a way to build something quickly and be listening to music ASAP.
I'm sure there will be plenty of people (myself included) willing to buy the ACA if he decides he wants to sell it later on.
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Note that I have built the TQWT speakers, not the DTQWT with the extra 12" bass driver. I listen in a 4x10m room however the speakers fire down the shorter 4m length. The bass on the TQWT's is impressive, it is deep, full and articulate. I listen to a lot of bass-heavy music and I am completely satisfied with how they perform.
In your (large) room I would be tempted to go for the DTQWT, if the physical size of the speaker is not an issue. I am sure the DTQWT would work in my room, however it is just a touch too large for our living room, wouldn't be very WAF friendly.
BTW just noticed on Troel's site he mentions PassLabs amps:
In your (large) room I would be tempted to go for the DTQWT, if the physical size of the speaker is not an issue. I am sure the DTQWT would work in my room, however it is just a touch too large for our living room, wouldn't be very WAF friendly.
BTW just noticed on Troel's site he mentions PassLabs amps:
Depends on the speaker. The F5 will get some more detail out of the top
on what otherwise might be a slightly dull top end. Plenty of speakers like
that.
On the other hand, with something like the Lowthers or Feastrex which are
slightly exaggerated in the upper mid / lower top you can get an effect that I
call "instant coffee in a microwave oven"
If you don't like that, then an F3 or F6 have a more relaxed character.
The J2 sits kind of in the middle.
A better way to say this might be if you listen at 0.5W peaks (95dB speakers) at 2.5 metres you'll be using 2W at 5 metres.
Did the same route. I had built AudioNoteKits kits previously, and was using the PP EL34 amp (35watt). Having read about the Pass gear for years, I built the ACA kit for my Zu Audio Essence speakers(since upgraded to the Druid Vs).
Sure they sounded great together, at lower volumes, and with Jazz and vocals. But.
When the Aleph J clone came to be, the sound came alive with all genres of music, and was better at exciting my small room at higher volumes.
Still, the ACA is a great way to test the waters, and hear what these amps sound like. You are headed in the right direction. Enjoy!
Sure they sounded great together, at lower volumes, and with Jazz and vocals. But.
When the Aleph J clone came to be, the sound came alive with all genres of music, and was better at exciting my small room at higher volumes.
Still, the ACA is a great way to test the waters, and hear what these amps sound like. You are headed in the right direction. Enjoy!
Well, that's a subjective call, but the J2 has more bandwidth in both
directions, lower distortion, more damping, more feedback. It's a two
stage amp, where the F6, but for the neutral (and optional) input buffer, is a
single stage piece.
Anyway I can listen to either without complaint.
I have a pr of ACA monobloks. My room is big, and of the many speakers none are more than 90 dB. 99% of the time 5w is, amazingly, sufficient. I'm guessing they clip very nicely
dave
I have a pr of ACA monobloks. My room is big, and of the many speakers none are more than 90 dB. 99% of the time 5w is, amazingly, sufficient. I'm guessing they clip very nicely
dave
Yeah. I agree, I feel most people overestimate what they need. The ACA is a very nice amp for listening at sensible/enjoyable sound pressure levels.
The F6 and AlephJ are also great amps too.
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I have a nominally 95dB speaker which was working well with a tube amp that I'd guess was able to put out 2W to 3W when the wind was behind it. I have replaced it with a JLH 1969 Class A amplifier that on paper puts out 8W peak (based on the power supply rail voltage) and it never gets turned up much - I can easily see 5W being plenty. And I'm using mono, so that's only one channel at a few Watts playing into a fairly generous living room. You'll have stereo, so that's double what one channel is rated out - I reckon that'll be plenty.
Just completed the ACA's (built them in 2 evenings) and have them playing for the first time as I am typing this. Eye opening on many fronts. They sound as if they have unlimited reserves of power even on heavy pounding music. And this with 6W, insane. With even just a few minutes on them they sound transparent, resolving and tonally colourful. I'm sure they will open up further as the caps and various components break in but they have already exceeded expectations.
It was huge fun putting these together and I feel ready to take on the F6 and Aleph J builds for which I am gathering parts. Totally hooked now!
It was huge fun putting these together and I feel ready to take on the F6 and Aleph J builds for which I am gathering parts. Totally hooked now!
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