PA-1 amps

[leonski]

If it's as low as I suspect, like 1 watt or less, a Kill-A-Watt meter will be at its lower limit.

Let us know when you have a result......

[AudioHTIT]

Sept 10, 2018 22:45:18 GMT -5 leonski said:

If it's as low as I suspect, like 1 watt or less, a Kill-A-Watt meter will be at its lower limit.

Let us know when you have a result......

I’ve been using the meter on my outdoor transformer as I replace landscape bulbs with LEDs, down about 300W so far and with much more light!

[leonski]

I replaced my 75watt outdoor floodlights with a pair of the similar output LED version. A fraction the weight and just over 20% of the power consumption.

Will your transformer meter resolve such a low power from your amps simply being ON than unplugging?

The meter I suggest, the Kill-A-Watt is reasonable and maybe 25$ in this market. Your local Home Store might even have 'em.

The Kill-A-Watt will also measure current, line voltage AND compute watts / VA and therefore Power Factor. The Last? You can consider that one as a measure
of how reactive the load is. The greater the difference between VA and WATTS, the more reactive. Power company would LOVE for all loads to be straight resistive.

[AudioHTIT]

Sept 11, 2018 11:44:54 GMT -5 leonski said:

I replaced my 75watt outdoor floodlights with a pair of the similar output LED version. A fraction the weight and just over 20% of the power consumption.

Will your transformer meter resolve such a low power from your amps simply being ON than unplugging?

The meter I suggest, the Kill-A-Watt is reasonable and maybe 25$ in this market. Your local Home Store might even have 'em.

The Kill-A-Watt will also measure current, line voltage AND compute watts / VA and therefore Power Factor. The Last? You can consider that one as a measure
of how reactive the load is. The greater the difference between VA and WATTS, the more reactive. Power company would LOVE for all loads to be straight resistive.

Yes, it’s a Kill-O-Watt meter, I just meant my transformer is currently plugged into it to monitor my outdoor LED replacement project. When the PA-1 arrives I’ll do some measurements; standby, idle, average loud. Since my PA-1 will be plugged into the triggered outlet box I linked a couple posts up, it won’t be powered when in ‘standby’, and I’ll leave it in the ‘on’ position, but I’ll measure it in the ‘auto’ position before plugging in there. However I’ll also measure the trigger box to see what it draws.

[leonski]

Meter isn't that 'fast'. So, if you are curious, you might play a 1khz tone to measure current draw of amp.

At that point? PLEASE try to find the Power Factor, too. I doubt a Switcher will be much over 0.85 in that measure.

[AudioHTIT]

Sept 9, 2018 13:07:01 GMT -5 AudioHTIT said:

Was about to order the PA-1’s to try on my Maggies, but forgot about no trigger, that and no power switch might make it a no go for me. ...

So feel free to point out mistakes in my thinking ... or my blatant inability to see the power switch next to the power connector.

The PA-1’s arrived today, only took one out of the box so far while the housekeepers are here. Small, light, nicely packed (do we have Oppo to thank for the little black covers?). Noticed the power switch right away so went back to check the picture, sure enough it’s there, in the specs too ... DOH! No matter, I now have nicely installed trigger controlled outlets that will make things easier and keep me firmly planted on the sofa (more about that later).

I took a few measurements while waiting in the garage.

Measured with KILL A WATT P3

Standby: plugged in, power on, auto position, no input, no load
Yellow light seen inside, nothing visible on front panel
Voltage: 123.7 VAC/60Hz, Amperage 0, Wattage 0, Volt/Amps 0, KWH 0 PF=1
Yes, nothing measurable (but there is a yellow light)

On: plugged in, power on, on position, no input, no load
Blue light seen on front panel

Voltage: 124.3 VAC/60 Hz, Amperage 0.09, Wattage 5.5, Volt/Amps 11.8, KWH 0.00 PF 0.46

I’ll add this to the Power Thread when I get them installed, need to finish a cable.

[leonski]

GREAT JOB on the actual measures. At that power level, which is near the bottom of resolution for the K-A_W, the power factor is irrelevent.

IF you get an opportunity, when playing music or perhaps a test tone at maybe 85db or NO LOUDER than 90db (that's REAL loud, btw) I'd be curious about steady state power draw and the PF.

The ratio of VA to WATTS should be expressed as the PF.......

[AudioHTIT]

Got the PA-1’s hooked up to my Magnepan 20.1’s (that just sounds odd). I had to build a couple XLR splitter cables and add a bit of logic to get the new triggered outlets to come on and the XPA-7 to shut off. The XMC-1 feeds both 2.2 Stereo and 7.2 Surround Systems. Since the Credenza was mid stream, I packed up my VTL’s before last ski season, this is the first I’ve listened to the Maggie’s in almost a year, what a delight! The ribbons open up the top end and the imaging with the old cabinetry gone is superb. The PA-1’s are doing a very respectable job, but so far I’m just having fun and getting things dialed in.

While I was setting levels for the Maggie’s XMC preset I took some more power measurements, using the pink noise in the setup makes this semi-repeatable.

I thought I’d start with the standard 2.83V at the speaker terminals, and the XMC’s 75 dB pink noise test put us right there with the voltage bouncing around between 2.75 and about 3 Volts. Coincidently this measured almost exactly 75 dB at my listening position (as Hannibal Smith would say “I love it when a plan comes together”). I then bumped up to the the 85 dB test and took readings again.

Here are the Kill A Watt readouts on the PA-1 at those levels.
XMC-1  75dB Speaker Speaker Level Test ~2.85vac at speaker
Voltage: 124.6 VAC/60 Hz,  Amperage 0.13, Wattage 7.7, Volt/Amps 16.4, PF 0.45

XMC-1  85dB Speaker Speaker Level Test ~9vac at speaker
Voltage: 124.8 VAC/60 Hz,  Amperage 0.38, Wattage 25-26, Volt/Amps 48, PF 0.52

[garbulky]

Sept 19, 2018 17:11:27 GMT -5 AudioHTIT said:

Got the PA-1’s hooked up to my Magnepan 20.1’s (that just sounds odd). I had to build a couple XLR splitter cables and add a bit of logic to get the new triggered outlets to come on and the XPA-7 to shut off. The XMC-1 feeds both 2.2 Stereo and 7.2 Surround Systems. Since the Credenza was mid stream, I packed up my VTL’s before last ski season, this is the first I’ve listened to the Maggie’s in almost a year, what a delight! The ribbons open up the top end and the imaging with the old cabinetry gone is superb. The PA-1’s are doing a very respectable job, but so far I’m just having fun and getting things dialed in.

While I was setting levels for the Maggie’s XMC preset I took some more power measurements, using the pink noise in the setup makes this semi-repeatable.

I thought I’d start with the standard 2.83V at the speaker terminals, and the XMC’s 75 dB pink noise test put us right there with the voltage bouncing around between 2.75 and about 3 Volts. Coincidently this measured almost exactly 75 dB at my listening position (as Hannibal Smith would say “I love it when a plan comes together”). I then bumped up to the the 85 dB test and took readings again.

Here are the Kill A Watt readouts on the PA-1 at those levels.
XMC-1 75dB Speaker Speaker Level Test ~2.85vac at speaker
Voltage: 124.6 VAC/60 Hz, Amperage 0.13, Wattage 7.7, Volt/Amps 16.4, PF 0.45

XMC-1 85dB Speaker Speaker Level Test ~9vac at speaker
Voltage: 124.8 VAC/60 Hz, Amperage 0.38, Wattage 25-26, Volt/Amps 48, PF 0.52

Glad to hear. I would be impressed in hearing what you think of the PA-1 sound quality when you feel you have a handle on the sound. Thanks!

[leonski]

Excellent data and should be repeatable. It would appear you were fairly careful in the setup and execution.

One reason for the db output is that Maggies are pretty much a LINESOURCE and will not 'fall off' as quickly as a box speaker.

You could make some quick checks by using ONE speaker, doing a setup for a certain voltage and SPL than going to various distances
with th measurement mic. The only change is measurment distance which will give you the opportunity to see the distance / spl relationship.
At some point, the room might take over with the echo or simply the 'liveness' of the room predominating.   

Extra Credit for the REAL overachiever would be to go out to your driveway or OUTDOORS with no or fewest reflective surfaces and repeat.
This quasi-anechoic response will really consume power.    And the difference will be simple room reflection.    One other possible way would be
to TIME LIMIT your measurement 'window' to 5ms ro 10ms so room reflections are excluded.   Either way works!
That might be possible using REW.

2.83v is 1 watt, indeed, but @8ohms. I think 1 watt @4ohms is only 2 volts. Somebody Check My Math!

Feeding your panel pink noise should give a good 'average' impedance from the speaker. The ribbon is fairly low, but you aren't measuring just that.

The only point of even minor concern is the PF, which is very low. Frankly, I'm surprised. I'd have predicted something around 0.8 or so. The power supply is
hugely wasteful in that sense. The idea is you USE VA but are charged for WATTS. I know, for example, that my Fluorescent lamp, a 4' tube / 40 watts, starts out with
a fairly low PF and it rises for the first 10 to 15 minutes than is stable.

[AudioHTIT]

Sept 19, 2018 18:26:51 GMT -5 leonski said:

Excellent data and should be repeatable. It would appear you were fairly careful in the setup and execution.

Thanks, I’ve done this before, but hadn’t used the XMC’s setup as a formal test generator, it does make for a easy standard test.

One reason for the db output is that Maggies are pretty much a LINESOURCE and will not 'fall off' as quickly as a box speaker.

I learned that from Harold Bevridge when I sold his line source electrostats, A true point source drops off with the inverse square law, -6 dB every doubling of the distance, a true line source drops 3 dB every doubling of distance (anechoic). Harold was a very sharp guy and a real gentleman, he made wonderful speakers.

You could make some quick checks by using ONE speaker, doing a setup for a certain voltage and SPL than going to various distances with the measurement mic. The only change is measurment distance which will give you the opportunity to see the distance / spl relationship. At some point, the room might take over with the echo or simply the 'liveness' of the room predominating.

I’ve never done that in this room, might be fun to see how the Maggies drop off compared to the B&Ws. The room is unusual, not many parallel surfaces, but symmetrical, and very big.

Extra Credit for the REAL overachiever would be to go out to your driveway or OUTDOORS with no or fewest reflective surfaces and repeat. This quasi-anechoic response will really consume power. And the difference will be simple room reflection. One other possible way would be to TIME LIMIT your measurement 'window' to 5ms ro 10ms so room reflections are excluded. Either way works!
That might be possible using REW.

Too much work, now we’ve stopped having fun, I have some frog speakers out by the driveway I can measure. Long ago I dragged some of the best speakers of the day into the anechoic chamber at Sacramento State University. A Bevridge Model 3, one of Roger West’s early Sound Labs (still one of the best speakers around), and I think the first generation of B&W 801. Did frequency and polar plots, they had a lot of good measurement gear at the time. Wish I could find the paper I wrote. It was pretty cool to have a resource like that available.

2.83v is 1 watt, indeed, but @8ohms. I think 1 watt @4ohms is only 2 volts. Somebody Check My Math!

I don’t know when it happened, but they always used to give sensitivity as SPL w/ 1W @ 1M, but as you say that’s impedance dependent. It seems at some point they started giving it as 2.83 V at 1M, making it constant across all loads. Seems like a good idea, I could be wrong, don’t look at that stuff too much anymore.

Feeding your panel pink noise should give a good 'average' impedance from the speaker. The ribbon is fairly low, but you aren't measuring just that.
The only point of even minor concern is the PF, which is very low. Frankly, I'm surprised. I'd have predicted something around 0.8 or so. The power supply is hugely wasteful in that sense. The idea is you USE VA but are charged for WATTS. I know, for example, that my Fluorescent lamp, a 4' tube / 40 watts, starts out with  a fairly low PF and it rises for the first 10 to 15 minutes than is stable.

I expected higher too, but maybe I needed to bump the signal another 10dB, in any case I’m happy the idle wattage is so low (compared to about 275 Watts on my VTLs)

[leonski]

I kind of made a study of speaker reactance some time ago. Seems a highly reactive speaker can simply suck the life out of less than capable amp. Some amps are reaaly good into a resistor and than go on vacation when
asked to drive any reactance over maybe 30 degrees.

The other thing that popped up was the Power Company will bring a surcharge to those big users who have a power factor proglem. Maybe 0.8 is the cutoff? In any event, factories with (for example) huge numbers of capacitor start motors
or other PF shifting loads end up with a small surcharge on their monthly bill. The company I worked for had a 6 digit monthly bill. We had over 40 large 'tubes' for the manufacture of semiconductor devices (some went to 1200c) as well as
all the support equipment filling a 90,000 sq/ft facility. Each of the 7 implanters, for example, had a transformer larger than an end table.

Maybe the PF of the amp improves (increases) at higher power levels or as it 'warms'. ??

[garbulky]

Sept 20, 2018 0:34:44 GMT -5 AudioHTIT said:

Sept 19, 2018 18:26:51 GMT -5 leonski said:

Excellent data and should be repeatable. It would appear you were fairly careful in the setup and execution.

Thanks, I’ve done this before, but hadn’t used the XMC’s setup as a formal test generator, it does make for a easy standard test.

One reason for the db output is that Maggies are pretty much a LINESOURCE and will not 'fall off' as quickly as a box speaker.

I learned that from Harold Bevridge when I sold his line source electrostats, A true point source drops off with the inverse square law, -6 dB every doubling of the distance, a true line source drops 3 dB every doubling of distance (anechoic). Harold was a very sharp guy and a real gentleman, he made wonderful speakers.

You could make some quick checks by using ONE speaker, doing a setup for a certain voltage and SPL than going to various distances with the measurement mic. The only change is measurment distance which will give you the opportunity to see the distance / spl relationship. At some point, the room might take over with the echo or simply the 'liveness' of the room predominating.

I’ve never done that in this room, might be fun to see how the Maggies drop off compared to the B&Ws. The room is unusual, not many parallel surfaces, but symmetrical, and very big.

Extra Credit for the REAL overachiever would be to go out to your driveway or OUTDOORS with no or fewest reflective surfaces and repeat. This quasi-anechoic response will really consume power. And the difference will be simple room reflection. One other possible way would be to TIME LIMIT your measurement 'window' to 5ms ro 10ms so room reflections are excluded. Either way works!
That might be possible using REW.

Too much work, now we’ve stopped having fun, I have some frog speakers out by the driveway I can measure. Long ago I dragged some of the best speakers of the day into the anechoic chamber at Sacramento State University. A Bevridge Model 3, one of Roger West’s early Sound Labs (still one of the best speakers around), and I think the first generation of B&W 801. Did frequency and polar plots, they had a lot of good measurement gear at the time. Wish I could find the paper I wrote. It was pretty cool to have a resource like that available.

2.83v is 1 watt, indeed, but @8ohms. I think 1 watt @4ohms is only 2 volts. Somebody Check My Math!

I don’t know when it happened, but they always used to give sensitivity as SPL w/ 1W @ 1M, but as you say that’s impedance dependent. It seems at some point they started giving it as 2.83 V at 1M, making it constant across all loads. Seems like a good idea, I could be wrong, don’t look at that stuff too much anymore.

Feeding your panel pink noise should give a good 'average' impedance from the speaker. The ribbon is fairly low, but you aren't measuring just that.
The only point of even minor concern is the PF, which is very low. Frankly, I'm surprised. I'd have predicted something around 0.8 or so. The power supply is hugely wasteful in that sense. The idea is you USE VA but are charged for WATTS. I know, for example, that my Fluorescent lamp, a 4' tube / 40 watts, starts out with  a fairly low PF and it rises for the first 10 to 15 minutes than is stable.

I expected higher too, but maybe I needed to bump the signal another 10dB, in any case I’m happy the idle wattage is so low (compared to about 275 Watts on my VTLs)

Care to share any further impressions? Inquiring minds would like to know!

[Boomzilla]

And a-standa-by, youse curious minds. The garbulky will soon do a side-by-side comparison of the PA-1 mono amps vs. the XPA-1 (gen. 2). He doesn't know this yet, but surprise!

The gar's system is highly revealing (DC-1 straight via XLR to the amps and a pair of Axiom M-80 speakers - no fuss, no muss - clean & accurate). Also, the gar, being a young'un, has excellent ears and a discerning brain. Will the latest Emotiva Class-D wonders wow him? Enquiring minds want to know!

[novisnick]

Oct 4, 2018 5:28:35 GMT -5 Boomzilla said:

And a-standa-by, youse curious minds. The garbulky will soon do a side-by-side comparison of the PA-1 mono amps vs. the XPA-1 (gen. 2). He doesn't know this yet, but surprise!

The gar's system is highly revealing (DC-1 straight via XLR to the amps and a pair of Axiom M-80 speakers - no fuss, no muss - clean & accurate). Also, the gar, being a young'un, has excellent ears and a discerning brain. Will the latest Emotiva Class-D wonders wow him? Enquiring minds want to know!

This is great! His review will be well thought out fair and articulate! Some good reading coming our way. AFTER a fair amount of listening. Poor guy! But somebody has to do it.
Have fun garbulky

[craigl59]

Am very interested in a Garbulky review of the PA-1 and wonder how it can be compared to the XPA-1. They are different price points and completely different topology. Make it clear for us, G-man...

[leonski]

I predict surprise is coming. But I won't tip the scale by tipping my hand....or thoughts.

[garbulky]

Oct 4, 2018 10:07:46 GMT -5 craigl59 said:

Am very interested in a Garbulky review of the PA-1 and wonder how it can be compared to the XPA-1. They are different price points and completely different topology. Make it clear for us, G-man...

Well I am going to be VERY excited to to do this review. Currently I have removed the jumpers from my axiom speakers and use all four terminals on my XPA-1 amps. Since the new amps have only two terminals So I am going to have to pull out some old bzilla handmade MASSIVE biwire cables to work with these amps. Think like 4 guage thickness!

Previous non Emotiva amps have trouble getting a certain "fullness" out of my speakers including some Crown XLS amps. It's almost like they strain in the mids even at low volumes leaving a hole in the middle creating small tonal differences in audio. It would be interesting to see how the PA-1's do as they are Emotiva's first ICE amps. From what I gather they are essentially unmodified - simply stuck in an Emotiva chassis. So I'm not sure what to expect!

[garbulky]

Hi guys,
I spent a short while with the PA-1 amps. They are run fully balanced from a DC-1 to Axiom M80 speakers. Source: Musiland Digital times via BNC. I'll be comparing to my XPA-1 gen 2.

Current subjective impressions - very very fast amplifiers. They may be faster than the XPA-1 which is the fastest amp I've heard.
Therefore it has lots of soundstage. Placement was getting pretty impressive like in a Peter Paul and Mary where one of the two men showed up right by my ear. Lots of control in microdynamics. This ability allows for more details and expression to emerge from the sound. Little shy on bass. Has a treble lean to it. Think bright and airy. Lots of power. Quite enjoyable. I wouldn't use it with Saber DACs due to it already having a treble lean.

Also got to give props to the AMAZING form factor. They really should have had trigger inputs for this unit.

They sound very like B'zilla's Heathkit tube monoblock amplifier in that the sound is very fast, vivid, holographic and a little tilted towards the treble. However it is less colored in frequency response than the Heathkit's.

I'm a tone junky, so my main complaint is that the tone isn't quite right. I've recorded myself and though it sounds really impressive the balance on my voice and my wife's and the acoustic instruments we play aren't quite correct.
Since it only has had a short use, and I may be getting fooled by the treble leaning sound signature, I will reserve proper judgment. I expect things will change over time, hopefully the bass gets stronger and more importantly the treble gets toned down slightly. Stay tuned!

[leonski]

And perhaps.......just Maybe......your ears will 'break in' as well?

Thanks for early report.