What a big vacuum tube! Single Ended Mono Block Power Amplifier

[DanielT]

I was most interested, or should I say fascinated, about the size. Just wanted to show it.

Here is information from the manufacturer:

"Power Output max. 170 Watts @ 1 kHz
Noise 110 dB below rated output "A" weighted"

They didn't write anything about distortion levels.

They write a lot about damping factor. Something of a "super damping factor". I don't know what it is, a good damping factor? About Damping factor they write:

"Damping factor 8 ref. to 8 ohm load @8 ohm tap, 32 ref. to 8 ohm load @4 ohm tap (super damping factor mode), both @ zero global feedback."

Good or not? I do not know. I was most fascinated by the size of that power vaccum tube.Just wanted to show it:

NAT - Innovative Audio Manufacture - Magma New HPS

Single Ended Mono Block Power Amplifier Our flagship series power amplifier! >HPS version is much more improved than the standard version!< NAT...

www.nataudio.com

To get an idea of the size check out this video. A picture from the video, the amp on the far left has the 300B power vaccum tube. The amp on the far right is the big Magma New HPS:

13:45 into the video:

 

[egellings]

The height of silliness

 

[DonH56]

A damping factor of 32 is four times better than the base factor of 8, but neither is really "good". But 32 is high enough to work with many more speakers than 8.

Damping factor article: https://www.audiosciencereview.com/...amping-factor-and-speakers.23968/#post-807327

HTH - Don

 

[sergeauckland]

 

[sarumbear]

Frequency Response

9 Hz to 70 kHz -3dB

They state the output impedance is 64 or 256 ohms. How they managed such a wide FR at a relatively high output impedance I wonder?

 

[egellings]

They state the output impedance is 64 or 256 ohms. How they managed such a wide FR at a relatively high output impedance I wonder?

If the impedance of the device it drives is resistive only, then a flat FR would be possible with a Zo that high.

 

[sarumbear]

If the impedance of the device it drives is resistive only, then a flat FR would be possible with a Zo that high.

The source is a transformer, this is a vacuum tube amplifier…the resistance of the secondary winding is a small portion of the output impedance I expect.

 

[DanielT]

The height of silliness

When I first saw a picture of it, I wondered if it was a joke, or just some lamp, something along the lines of steampunk aesthetics (or art deco inspired, old street lighting lamp approximately ) , but apparently it's a working amplifier.

You know those who are almost obsessed with tube amps will probably buy it.Price tag on it? I don't know, but it probably isn't cheap.It might be good. That is, good performance, measures well if tested. What do I know.

A damping factor of 32 is four times better than the base factor of 8, but neither is really "good". But 32 is high enough to work with many more speakers than 8.

Damping factor article: https://www.audiosciencereview.com/...amping-factor-and-speakers.23968/#post-807327

HTH - Don

Aha, I missed that number 32. Then I understand.

Edit
Price is stated by that youtubetubedude:

 

[DonH56]

They state the output impedance is 64 or 256 ohms. How they managed such a wide FR at a relatively high output impedance I wonder?

Output impedance is inversely related to damping factor, DF = Zload/Zout, so Zout = Zload/DF.

DF = 8 into 8 ohms means output impedance is 8/8 = 1 ohm. DF = 32 into an 8-ohm load means output impedance = 8/32 = 0.25 ohms, actually pretty good for a tube amplifier.

 

[FrantzM]

This was amusing ...
I will nonetheless, not forgive @DanielT for the watts I consumed watching this video...

When you think you've seen it all...

Peace.

 

[levimax]

I can see the appeal of these to some people and I am sure they sound fine but I would not want to be in the same room with 2 of these unless it was both air conditioned and fire proof. With over 1,000 volts on the plates I would also not want to touch them to turn them on or off. No doubt your friends and neighbors would be impressed and the psychoacoustic power of 2 of these in a room would result in almost everyone saying "this is the best system I have ever heard".

 

[GeorgeWalk]

A good space heater and poor reading lamp.

 

[DanielT]

This was amusing ...
I will nonetheless, not forgive @DanielT for the watts I consumed watching this video...

When you think you've seen it all...

Peace.

Just because you liked the last video, ..here's another one:

Damn, how big those vaccum tubes are, check 2:50 into the video:

I can translate what is said in the video, even though I don't know the language: ..One of the best tube amps ever made. The soundstage is huge and it cannot be described it must be experienced. This is sound on a whole new level. Power, details are...and so on.
(I'm just kidding, it might be good)

I can see the appeal of these to some people and I am sure they sound fine but I would not want to be in the same room with 2 of these unless it was both air conditioned and fire proof. With over 1,000 volts on the plates I would also not want to touch them to turn them on or off. No doubt your friends and neighbors would be impressed and the psychoacoustic power of 2 of these in a room would result in almost everyone saying "this is the best system I have ever heard".

As heating elements this winter, albeit two rather expensive ones.

 

[FrantzM]

I can see the appeal of these to some people and I am sure they sound fine but I would not want to be in the same room with 2 of these unless it was both air conditioned and fire proof. With over 1,000 volts on the plates I would also not want to touch them to turn them on or off. No doubt your friends and neighbors would be impressed and the psychoacoustic power of 2 of these in a room would result in almost everyone saying "this is the best system I have ever heard".

They don't sound fine.
Well not this one, I have heard some of these SET monstrosities back when ... and for the life of me, could not understand the appeal.. weak bass and treble .. what is left is the midrange and it is always "glorious", since that is all there is... Usually those flea-powered amplifier are paired with some full range driver nonsenses, with limited output and only midrange .. And while claiming that the music resides in the midrange, a warning for the severely limited in frequency range reproduction , you are about to suffer, they drop their needle (always Vinyl) and play some female vocalist (always) with small ensemble .. bass and treble will disappear in the vacuum of space, leaving a galactic-wide void ..... err.. soundstage ... but the midrange ...oh the midrange ...
... Measurements say they can't sound fine ..

Peace.

 

[egellings]

You just have to believe. Bee-leeeve!

 

[mhardy6647]

The scary part is the B+ voltage required.

 

[sarumbear]

... Measurements say they can't sound fine ..

Where can we see the measurements?

 

[egellings]

Those large tubes tend to have high plate resistances, so OPT turns ratios get large, which makes it hard to get a satisfactorily low leakage inductance. And then the insulation has to be really good, too, with that much 'lectric all over the place. I pass on them.

 

[Philbo King]

Reminds me of the Power amp output finals of the 40 kW shortwave transmitters I used to repair.

 

[DanielT]

They don't sound fine.
Well not this one, I have heard some of these SET monstrosities back when ... and for the life of me, could not understand the appeal.. weak bass and treble .. what is left is the midrange and it is always "glorious", since that is all there is... Usually the fea-powered powered some full range driver nonsenses with limited output and only midrange .. And while claiming that the music resides in the midrange, a warning for the severely limited in frequency range reproduction , you are about to suffer, they drop their needle (always Vinyl) and play some female vocalist (always) with small ensemble .. bass and treble will disappear in the vacuum of space, leaving a galactic-wide void ..... err.. soundstage ... but the midrange ...oh the midrange ...
... Measurements say they can't sound fine ..

Peace.

Speaking of which, here Mr. Carlson tests a tube amp, FR and distortion with and without -10 dB negative feedback. How he can connect it, off and on, I don't really know because I haven't seen the whole video but in any case there is a difference, with negative feedback it will be a straighter FR and a little less distortion.

1:03:30 into the video, the FR and distortion measurements begin:

Without negative feedback:

With -10 dB negative feedback