Another marketing gimmick?


Put micro sized components in a glass structure that resembles a vacuum tube?
https://agdproduction.com/index.html

Im thinking pure aesthetics were the goal here. No need to put those "advances" mosfets in a glass tube?

I guess someone will buy it.
tablejockey
As far as I can tell that is the case,  pretty bizarre but as you say there will probably be a market.
Perfect for the buyer "innovative stuff?"

A look at the manual, and it appears the designer even put orange LED's in the faux tube. This thing is just....odd.

It better sound good for $14K! Plenty of SS amps for less, that sound great.
There's always a market for snake oil. The real question is how big that market will be.
I'll wager you could put the metronome inside a tube and it would stop that annoying "ticking" sound! 
OMG, you guys are becoming a cult.

That's just an aesthetic take on a what reviewers say is a great sounding amp. It's a Gallium nitride power FET device that only the maker has access to, since he designed it. All other GaN devices are for radar and if used for audio, are modified or backward engineered. It replaces silicon devices as it's way faster.

Here's a review of it: https://6moons.com/audioreview_articles/agdproductions/

The reason he put it in a tube is, wait for it, he's somewhat an artist as well as an engineer.

All the best,
Nonoise
How does it sound?  Why care about the looks, different yes, effective?  Would like to hear one.....I don't have the money to buy it.  Would still like to hear one with Magnepans.
Dwmaggie
Check out ocd hifi guy 
On YouTube he has videos of these amps playing through Maggie's
I have heard that amp, and in the system it was used it was exceptional. However, to make a firm judgment I would have to review it, that is, compare directly with several other amps. That, alone, would tell, as opposed to speculation. 

It is easy to be overawed by a novel design, but performance tells the truth. The only way to do so is compare. 

Anything new, unusual, etc. will draw criticism. The proof is in performance (and of course, dependability). I am reviewing a speaker that I'm sure many would mock due to appearance, but the performance is no laughing matter. Thankfully, I was not foolish enough to disregard the speaker due to its appearance only, or else I wouldn't be enjoying its surprisingly High End characteristics (And, yes, that is in comparison to other speakers). Sorry, no disclosure now; you'll have to wait for the review.  :) 

I cannot speak for the actual technical validity of the amp's circuit, but it is not unusual for nouveau methods and technology to be ridiculed, even when it outperforms. When a new and better technology appears the Old Guard fights because it means loss of popularity, sales, etc. 


@nonoise I am not a culter it just seems a bit silly. Whether it sounds good or not I have no opinion without hearing it.
Like @truthhouse said, check it out on OCD Hi Fi Guy’s YouTube channel before passing judgement. Of course you’re not gonna get the full experience through YouTube, but it gives you an idea of a great sounding Class D amp, which I was skeptical about too before I saw these vids. Thanks @nonoise for giving the facts about these amps and giving a basic explanation of them and the designer and engineer of these amps. Believe me, I’d love to hear them in real life too before coming to a final conclusion, but they certainly look cool IMO. 
@jond ,
That was just a bit of snark what with all the dog piling going on.
Nothing personal. 

All the best,
Nonoise
Another SOTA 'breakthrough', or 'Audiophile Jewelry'?

Truth be told only in the hearings, which any suspect should get it's day in court.....so to speak...*L* ;)

But, listening to anything playing through my playthings...still sounds like my stuff....to me.  If anyone can do a variant of 'astral projection' thru their 'puter, I'd like to know How, Please.

And it'd better work on 'live' stuff...'projecting' into a mpeg would merely dump you into a servers' hard drive or the like.....

I don't think I'd like that very much....:(

And if you think hackers or virus attacks are to be feared....

....you'd really not like a 'virtual ME'. *evil L* 

("Hmmm....bankaccountsSSA#passwords...*ah*...'incognito'...")
First, the newest class D amps are damned good, at least my EVS 1200 is, which is the 5th class D amp/s I've owned overt the last 5+ years, BUT, GaN is heralded as the a major advancement in musical clarity, in that it transitions much faster, meaning it's a clearer lens, similar to the finest camera optics, which are similarly expensive


GaN is the newest tech, with lots of R & D involved for audio applications, which makes it more expensive than even the best class D amps. That said, Underwood HiFi has just introduced the Voyager, a GaN amp for under $3K. WTH?


I am in high anticipation of having one very soon. Once I get to compare to my EVS 1200, I will start a thread on it

I'll never own an amp that uses LEDs to illuminate a tube. Fake and cynical. 
Thank you Dan D'Agostino. He started this back in the early 80's with Krell. Initially it was just thick face plates and gold screws. I would like to think his early Krell stuff sold because it really sounded good but soon other manufacturers climbed on board looking for ways to distinguish their equipment visually at least. Now if it looks good it must sound good and everything even wires got sucked in. As I have said before, all this money wasted on jewelry could have been spent on better engineering and components. We all pay for this. Pass Labs is a good example of a manufacturer who did not fall for this entirely. His designs are straight forward. He uses the same chassis parts across his model line to save money so you pay for performance. I could do without the meters. 
I wouldn't be surprised the amp sounds great. It's a $14K amp, with the latest transistor technology-it should!
https://www.audiogon.com/listings/lis9b494-agd-productions-vivace-monos-gallium-nitride-newest-techn...

The circuit in a tube thing just seems CORNY. It's a high performance amp-great. That kind of aesthetic however, belongs to low end Best Buy stuff.
To each his own.


Hey, I hope that it's a real push forward for D amps, frankly.

That tech is either lauded or dumped on with annoying regularity in the various forums, but it's already Everywhere...Your phone, the car, the tv, the laptop....anything that has to speak or sing or play sounds @ you.

It will only improve in the long run...not that A-A/B will disappear, but they're already being eclipsed....rapidly.

Yesyesyes...I understand and appreciate the 'warmth & nuance' of the tube.  The 'silk' of sound, if you will.  Combined with the 'right' components, not to easily rivaled by SS.

To the 'golden eared' amongst us, there will be no equal.

BUT....I'll wager that within this decade, it's going to get more difficult to discern the difference so quickly.  The music from behind that 'A/B curtain' will begin to fool the disclaimers.

That 'discussion' has been going on since the debut of the transistor...then, the IC....

In some ways, stuffing them into vacuum tube ought not to be a surprise.

You're looking @ what's happened after some bright sorts hooked a tv up to an early 'puter....and played PONG shortly after...

One can either get 'woke'...or prep for a coma. *G*

(Somebody buy this thing and run the cr*p out of it...that's the only way to see if it's worth getting excited about it.  Works for racing vehicles...see if it breaks, and how, and why.  Fix it, back to the track, and repeat as req'd.)

...until it doesn't. ;)






That’s just an aesthetic take on a what reviewers say is a great sounding amp. It’s a Gallium nitride power FET device that only the maker has access to, since he designed it. All other GaN devices are for radar and if used for audio, are modified or backward engineered. It replaces silicon devices as it’s way faster.

No, he designed the circuit, not the GaN FET used in it. He had some involvement when he was in the semiconductor industry, but it was not designed for his amplifier. It appears to be obsolete as well as he bough the remaining inventory and is changing to a different FET for newer designs. Your comment about all GaN are designed for radar is simply not true. Switching devices in power conversion (which is what a Class-D amplifier is), is a primary market for GaN and there are numerous devices designed specifically for this from a growing number of vendors. They are not even very expensive any more with low quantity orders under $2.00, and volume much less.


The switching FET is just one aspect of Class-D as well.

While Class-D is efficient, there is still heat generated. Putting it inside glass is going to maximize the temperature swing from turn-on till it reaches operating temperature. If you like to keep your amplifiers off, till used, it may not be ideal for consistent performance.

Marketing? .... Definitely, but the upgrade path is interesting and this method ensures the unit does not have to be opened. I wonder if those contacts are audiophile grade? $20-100 speaker binding post, $0.25 cent tube socket contact ..hmmmm.

audiozen, hopefully the tube socket has been 'improved' in some fashion unknown @ this point.  Time (and a curious purchaser) will tell the tale.

If the tube has been evacuated of air, I wonder if heat will be (or not) an issue.  The elements within the typical tube we're used to referring to 'glows' with it's current; IC's do employ heatsinks and fans to varying degrees and applications.  I wonder if using a noble gas within the tube might make a difference.  Nitrogen, used to inflate auto tires, makes them 'run' cooler, perhaps?

I would think that would be touted in the specs....I would.  "Exotica" such as this, esp. at that price point, could allay 'heat concerns'.

Just musing...
2034 @ your local Best Buy:

The GaN FET 'tube tester'....*L*

(You can say you saw it here, first...*L*)

Don't know if you're old enough to know or remember the 'tube testers' that were occasionally at local markets.  The better versions had a meter to give one an idea if it was 'marginal enough' to make it through the next football or baseball broadcast....

It'd generally punk out 3rd quarter.....*L*
If evacuated of air it would get hotter. There are some gases that would improve thermal transfer to the glass, but thermal conductivity of gases is inversely proportional to molecular weight, and they escape easiest .... i.e. helium and hydrogen. Neon may be a reasonable compromise. There are some more esoteric ones out there. Most of the heat transfer is because of the gas moving due to diffusion and chimney effects from the hot electronics.  With the electronics in a sealed enclosure like this, most of the heat transfer will be radiative.


Nitrogen is not a noble gas. It also does not make your tires run any cooler. That is an old myth. It may from a practical standpoint in that it escapes slightly slower than plain air so better chance your tire is properly inflated, but that's it.


The device I use was developed very specifically for class D audio, not for power supplies, low voltage points of load or RF circuits.
Yes, others use GaN devices but not the ones he worked on with the supplier and he bought out all the inventory. I don't know where you got the notion that the circuit is obsolete unless it was meant to demean. 

He's devising a new one to deal with the increased power of his next amp. Going back down in power doesn't appear to involve modifications. That, and although other makes use some form of GaN device, they're not intended for audio, like his are.

And, yes, I took some poetic license in saying that it was for radar as I was lazy to not list all the other applications. You're quite the pill, aren't you?

All the best,
Nonoise

The GaN device he is using is obsolete. That is why he had to buy up all the inventory. That is why he needs to switch to a new one for the next gen devices. Designed for class-D audio is specious. Designed for a particular implementation of Class D audio would be more accurate. That does not mean that new generic devices are not more appropriate to Class D either. When he says power supplies does he mean high voltage supplies as mentioned elsewhere in the article (or website) or the new low voltage GaN FETs that are low cost and very high performance? ( And could be why the old part is now obsolete, too expensive and not good enough). It’s sort of like power supply electrolytic audio capacitors. They used to be "superior" but circuit dependent a new low ESR, high temp, high life capacitor will be superior.


His circuit may be awesome and I am happy to see he is not running with blinders to the highest switching frequency at the detriment of other properties (as certain people promote), but also note he is switching much lower than say Cherry who does it with silicon transistors and has well respected sound (at less money).


And no, using "radar" makes you the pill, not me. If you were up on low voltage GaN for power supplies you would have said that but sure, claim someone else is the problem.
Using "radar" and providing the link with the attribution shows I was just lazy. Nothing more.

Your needling every and any point to better others shows you to be an audio (and carpet) harpy of the highest order. I think you’ve found your niche.

Carry on.

All the best,
Nonoise
Post removed 
Nope. My intention was not to look knowledgeable at all. You must not think that others do things for the same reasons you do.

As for personal attacks, you just mask them (sometimes poorly) in your rebuttals, but they do show. As for mine, it's just snark, making it easy to digest, and out in the open.

All the best,
Nonoise
A quick check of electronic device history indicates the GAN transistor is far from a "new" breakthrough.

https://en.m.wikipedia.org/wiki/Gallium_nitride

I took electronics 101 classes in the early 80's. Don't remember if Gallium was ever mentioned as an alternative material to silicon,for a semiconductor. 

What I clearly remember, is the Apple II computer was about to change EVERYTHING. That's at least, what the computer nerds kept telling me.

One instructor who was into audio, believed digital was going to blow everyone's mind, in the not too distant future. He thought vacuum tubes were stone age devices, and wrote them off.
A friend of mine was the youngest engineer at JPL at the time and he worked with Gallium nitride back then. That was in the late '70s. I don't know what the application was but he told me it was difficult and dangerous to work with.

All the best,
Nonoise