[CrazyBlue]

Just curious.

I know Class D amps are really light, but it seems like many comparable amps are nearly twice as heavy as say, the Synergy 450 @ 38 lbs. 

Parasound A21 is 60lbs

Emotiva XPA-2 is 72 lbs

Just a couple of examples on either side of the price range of the Synergy.

On the other hand, the Audio Research DS225 is also 38 lbs.

I know weight doesn't necessarily have much to do with sound quality, but I'm a curious guy and wonder about stupid stuff like this.  Maybe I need some sort of therapy.

 

[srb]

My guess is one of the largest factors would be the transformer.  Perhaps some of the comparisons have transformers that are larger than actually needed?

The gauge of the steel chassis would be the next contributor to weight.  But before someone says that superfluous thick aluminum faceplates are a big factor, the difference for example between 17"W x 6"H 6061 aluminum in 3/16" vs 3/8" thickness is less than 2 pounds.

BTW, the Audio Research DS225 is a Class D amplifier, and although it has a linear power supply, it can have a smaller transformer due to the increased efficiency of the amplifier vs Class A/B.

Steve

[CrazyBlue]

Yeah, in the old days I always sort of did correlate weight with SQ, lol, mostly because it usually meant a big transformer, and therefore plenty of available power. 

I wonder what size the transformer is in the Synergy 450. The ones in my Emotiva UPA-1 monoblocks are 300VA.  The amps weigh 25lbs each.

Whatever the case, I'm reasonably sure the Synergy would best mt UPAs across the board, as they should at more than twice the cost for two channels.  Like I said, I'm one of those how-it-works guys, at least with stuff that interests me, such as audio.

Maybe better circuit design doesn't require as much raw power to feed it.

[coke]

I recently moved and had to disconnect, pack, move, unpack, and reconnect all of my AVA gear.  It's heavy enough 


Also, here are some pics that may help the thread.

A21


600R


Synergy 450

[Big Red Machine]

Frank's electrons are lighter and airier than the others.

[charmerci]

I recently moved and had to disconnect, pack, move, unpack, and reconnect all of my AVA gear.  It's heavy enough 


Also, here's some pics that may help the thread.

A21


600R


Synergy 450

Well, it looks like that's the case! 

[decal]

The Audiophile transition ................


 +

 +

 =





 

[dB Cooper]

Can't wait for the "official" explanation. What strikes my eye though is what must be a much higher parts count in the Parasound. "Less-is-more" wouldn't seem to be part of their design philosophy.

[mark funk]

I have a Dynaco 416 it must come in at 55 or 60 lbs plus the C-100 with those ten large 10,000 mf caps another 10 lbs or so. Those Dynas had large lron transformers.




                                                                                                                                 

[tonyptony]

They're as heavy as they need to be.

[topround]

The Parasound is obviously a heavier/beefier chassis, fit and finish is top notch.
The Parasound also must have a heavier transformer. There definitly is more parts in the Parasound. But all those resistors and boards can't add  up to more than 5 or 6 pounds, so I would say chassis and transformer.

BTW the AudioNote Kits which resemble the AVA gear in layout are also pretty light. Parts count is low and the chassis are light.
Shipping from China gets expensive when it is heavy!

[CrazyBlue]

Well, I guess less is more.

The A21 isn't rated stable into 2 ohm loads.  Purty though..

[CrazyBlue]

Running two of these for the last two years: 200w@8, 350@4.  Starting my upgrades at the digital sources right now, just picked up a used Ultra DAC.  But am looking at preamps next, and like what I've read about the Transcendence Eight.  After that, the Synergy 450 looks like a good fit.

I only live about 100 miles from Frank, so that's convenient.  Going to swing by and have him do the mosfet upgrade on the Ultra, and hear some gear and those HT3s of his.

[CrazyBlue]

Man, that's just wrong...

[topround]

Not stable into two ohms
The damn thing was designed by John Curl! Wake up man

you might want to investigate who this guy is in the industry before attempting an insult
there is more to this hobby than numbers

[yeldarb]

I'm sure Frank would add some lead shielding if you want to buy by the pound.  Or pot the transformer with lead and epoxy.   

[avahifi]

Our power amplifiers are designed to be picked up and moved without need for a fork lift truck.

However the shielded toroid power transformer for the Synergy 450 is rated at 850VA and weighs 14 pounds.

Looking at the photos above, what you will notice is no unnecessary sheet metal, just a big very solid heavy gauge steel box with very efficient striated fined heat sinks.  This give them about twice the surface area as smooth finned equivalents and excellent heat dissipation.  We have never taken chassis damage from rough shipping handling, just a few minor cosmetic dings over the years.

Also, our circuits are not full of monkey motion or redundant protection circuits.  No relays because our amplifier do not generate on or off transients.  No low voltage protection because our circuits are up and running stably at 10 percent of AC line voltage.  The multiple regulated power supplies are built into the audio boards on the big amps, except for the output transistor regulators.  They regulated all the way up to and past output clipping.  No nasty sounds from these amplifiers ever.  No bias sensing and protection circuits because our power mos-fet output transistors have negative temperature coefficients and thus can never thermal runaway and thus need no external protection to prevent this.

Finally no ornate Rolex like chassis hardware to turn the amplifiers into audio jewelery.  They are just designed for audio musical bliss, not jewelery.

As an aside, at least my jewelery, a Rolex watch, is not so heavy it needs an arm sling to wear.  Even they had some rationality in their designs.

Regards,

Frank Van Alstine

[rollo]

  Light by design. Goal accomplished. Dave Bernings Zotl amp weighs 2 lbs. Weight means nothing unless your a tire kicker. A great design is a great design no matter the weight. KISS.


charles

[CrazyBlue]

Pretty much what I figured.  I like simple.

Also, our circuits are not full of monkey motion or redundant protection circuits.  No relays because our amplifier do not generate on or off transients.  No low voltage protection because our circuits are up and running stably at 10 percent of AC line voltage.  The multiple regulated power supplies are built into the audio boards on the big amps, except for the output transistor regulators.  They regulated all the way up to and past output clipping.  No nasty sounds from these amplifiers ever.  No bias sensing and protection circuits because our power mos-fet output transistors have negative temperature coefficients and thus can never thermal runaway and thus need no external protection to prevent this.

Thanks, Frank.

Like I said, just curious is all.  I like to understand—or try to—different design approaches.

The only jewelry I wear is my wedding ring.  It is pretty heavy though...

[CrazyBlue]

Not stable into two ohms
The damn thing was designed by John Curl! Wake up man

you might want to investigate who this guy is in the industry before attempting an insult
there is more to this hobby than numbers

Relax, man.  Your tongue-in-cheek detector is malfunctioning.