Dan D’Agostino ... What the world needs now is a $250,000 power amplifier ...

[RayDunzl]

https://dandagostino.com/products/relentless-monoblock.php

40A @240V = 10kw

 

[RayDunzl]

I have a pair of Krell FPB 350 mcx. They work well.

Here's some build pictures of one of the last amps before he lost control of Krell.

https://wizard-highend.blogspot.com/2012/01/building-up-of-krell-400e-mono-amp.html

 

[Jorj]

Good lord....10 kW. Is that PER unit?

At unity kVA = kW, so without knowing the power factor, that thing might require you to upgrade the distribution transformer on the pole by your house.

 

[DuxServit]

What kind of USB cable comes with it?

 

[Hugo9000]

Model : Relentless
$250,000 for the pair of amps in the US
£250,000 in the UK
AU$449,995 in Australia
1,500 watts into 8 ohm speakers, 3,000 watts for 4 ohms and 6,000 watts into 2 ohms
570 pounds (258kgs)

https://www-cnet-com.cdn.ampproject.org/v/s/www.cnet.com/google-amp/news/what-the-world-needs-now-is-a-250000-power-amplifier/?amp_js_v=0.1#referrer=https://www.google.com&amp_tf=From %1$s&ampshare=https://www.cnet.com/news/what-the-world-needs-now-is-a-250000-power-amplifier/

"D'Agostino loves to cook, so I asked about the parallels between cooking and designing amps, and he said cooking is like organic engineering with flavors and ingredients. Though he has pasta-making machines, he prefers rolling pasta by hand on a granite slab. The sensual aspects of cooking appeal to D'Agostino.
In 30 years of making pizza, he says he never made the same dough twice, for D'Agostino in the kitchen it's all about the feel and taste. He uses an electric pizza oven, but he's seriously considering building a brick oven at home. With food and audio, he's always trying to top himself."

Please buy those amps so that poor Mr. D'Agostino can finally afford a proper brick pizza oven and get rid of that horrible electric pizza oven!

(And some people probably thought the cooking thing was a bizarrely tangential anecdote, although I think it's clearly the motivation for the pricing of these amps. If he sells enough of them, perhaps he can afford to relocate an authentic pizzeria from Napoli to his home, brick by brick!)

 

[Sal1950]

I wonder if the US versions uses the two phase 240V plugs we have for washers and driers...

I doubt it. Nearly every relatively high power amp Atkinson measures at Stereophile fails to meet spec. He then reports it's due to sagging AC voltages which he doesn't hold constant. Kind of surprising since as maverickronin said above, if you can afford these amps, you sure as hell could afford to have a couple 220 feeds put in for them to ensure power delivery. That would also add to the mystique, no?

"The Centaur II 500 is specified as outputting 500Wpc into 8 ohms (27dBW), 1000Wpc into 4 ohms (27dBW), or 1600Wpc into 2 ohms (26dBW). With clipping defined as when the THD+noise in the output reaches 1%, I measured clipping powers of 550Wpc into 8 ohms (27.4dBW, fig.4) and 880Wpc into 4 ohms (26.4dBW, fig.5). While this latter power is less than specified, note that I do not hold the wall voltage constant during these tests. The 0.6dB measured shortfall into 4 ohms will not be any kind of problem. However, when I tried to measure the maximum output power into 2 ohms with one channel driven, that channel turned off at 700W (22.4dBW) and wouldn't turn back on. Each channel is protected by two 10A and two 30A fuses, and it turned out that one of the 10A fuses had blown. Replacing the fuse brought that channel back to life."
Read more at https://www.stereophile.com/content...er-amplifier-measurements#yPvuTv0La1IhZ8g3.99

 

[maverickronin]

I doubt it. Nearly every relatively high power amp Atkinson measures at Stereophile fails to meet spec. He then reports it's due to sagging AC voltages which he doesn't hold constant. Kind of surprising since as maverickronin said above, if you can afford these amps, you sure as hell could afford to have a couple 220 feeds put in for them to ensure power delivery. That would also add to the mystique, no?

Wow. I guess Stereophile can't afford it either.

Or do they do it intentionally to leave themselves an out for not shitting on the manufacturer when it doesn't meet spec?

 

[Blumlein 88]

Wow. I guess Stereophile can't afford it either.

Or do they do it intentionally to leave themselves an out for not shitting on the manufacturer when it doesn't meet spec?

My guess is they do it this way to show what happens in a typical users home. Most people won't have a dedicated line. They could, but you know most will not.

 

[mansr]

Please buy those amps so that poor Mr. D'Agostino can finally afford a proper brick pizza oven and get rid of that horrible electric pizza oven!

(And some people probably thought the cooking thing was a bizarrely tangential anecdote, although I think it's clearly the motivation for the pricing of these amps. If he sells enough of them, perhaps he can afford to relocate an authentic pizzeria from Napoli to his home, brick by brick!)

Buy those amps and use them to heat your pizza oven. Let the music you play influence the taste of the pizza.

 

[maverickronin]

Most people won't have a dedicated line. They could, but you know most will not.

Makes absolutely no sense to have a amp rated for that much more than your outlets can deliever, but I guess I should expect that by now...

 

[PierreV]

1- we'll be spared the typical "punch above their weight" review line
2- relatively cheap per kg compared to crappy dacs
3- absolute bargains compared to phones

 

[Sal1950]

Wow. I guess Stereophile can't afford it either.

My guess is they do it this way to show what happens in a typical users home. Most people won't have a dedicated line. They could, but you know most will not.

Makes absolutely no sense to have a amp rated for that much more than your outlets can deliever, but I guess I should expect that by now...

Most US wall sockets are 120V15A lines. I do wonder if a big honking dedicated 120V/20A line would improve the situation or would it take a 220V line? Are models configured for a 220 line even available for purchase in the US? It does appear that DD has a 220 model available or switchable for the Relentless, quoted from their site,

"With its 5.5-kilowatt power supply feeding roughly 100 output devices, the Relentless Monoblock easily delivers 1,500 watts into 8 ohnd when connected to a 220-volt outlet, it doubles its output to 3,000 watts into 4 ohms and 6,000 watts into 2 ohms, all while maintaining the same musical composure it offers at a mere 1 watt."

We got even more interesting results from John's measurement of the DD Progression Monoblocks back in 9/2017. Make of these what your will?

"When I measured how the percentage of THD+N varies with output power into 8 ohms and 4 ohms, I got lower power than specified. With "clipping" defined as when the THD+N reaches 1%, the Progression clipped at 460W into 8 ohms (26.6dBW), which is 0.4dB lower than the specified 500W, and 690W into 4 ohms (25.4dBW), this 1.6dB lower than the specified 1kW into this load. When I tried to test the clipping power into 2 ohms, the amplifier turned itself off at 750W and just before then, I could hear the amplifier acoustically buzzing, and a burst of static through the FM radio I keep tuned to NPR in the test lab.
When Dan D'Agostino received the initial preprint of this review, he was concerned that this behavior indicated that the amplifier had suffered some sort of damage on its way to me from Jason Serinus. (After it had been picked up from Jason, the amplifier had been shipped to a dealer before it eventually found its way to me.) I was therefore sent a new sample of the Progression Mono (serial no. PMO100P), which had been fully checked out on the test bench, to test.
The voltage gain, input impedance, and frequency response of this sample were identical to those of the first, though the output impedance was slightly lower, at 0.32 ohms, and there was no RF noise present at the amplifier's output. And when I examined how the percentage of THD+N varies with output power, this sample clipped at 595W into 8 ohms (fig.4), which is 0.8dB higher than the 500W specification. Into 4 ohms, the clipping power was 934W (fig.5); though this is 0.3dB lower than the specification, I don't hold the wall voltage constant during these tests, feeling that this is more representative of an amplifier's behavior in a typical system. The wall voltage was 120.1V with the amplifier idling, but had dropped to 115.4V at 934W into 4 ohms.

Read more at https://www.stereophile.com/content...er-amplifier-measurements#cvirJFOXbXRKG0vd.99"

Bottom line is it may be true the customer has neither need or use for the max power these amps are capable of. But don't you think the manufacturer should supply these amps configured in a way making them capable of meeting spec? In my mind that would be a US 220 cord and have the customer have the correct feeds installed. End of rant. LOL

 

[andreasmaaan]

With food and audio, he's always trying to top himself.

Wow. Took some googling to realise that means something very different in American English.

 

[andreasmaaan]

Most US wall sockets are 120V15A lines. I do wonder if a big honking dedicated 120V/20A line would improve the situation or would it take a 220V line? Are models configured for a 220 line even available for purchase in the US? It does appear that DD has a 220 model available or switchable for the Relentless, quoted from their site,

"With its 5.5-kilowatt power supply feeding roughly 100 output devices, the Relentless Monoblock easily delivers 1,500 watts into 8 ohnd when connected to a 220-volt outlet, it doubles its output to 3,000 watts into 4 ohms and 6,000 watts into 2 ohms, all while maintaining the same musical composure it offers at a mere 1 watt."

We got even more interesting results from John's measurement of the DD Progression Monoblocks back in 9/2017. Make of these what your will?

"When I measured how the percentage of THD+N varies with output power into 8 ohms and 4 ohms, I got lower power than specified. With "clipping" defined as when the THD+N reaches 1%, the Progression clipped at 460W into 8 ohms (26.6dBW), which is 0.4dB lower than the specified 500W, and 690W into 4 ohms (25.4dBW), this 1.6dB lower than the specified 1kW into this load. When I tried to test the clipping power into 2 ohms, the amplifier turned itself off at 750W and just before then, I could hear the amplifier acoustically buzzing, and a burst of static through the FM radio I keep tuned to NPR in the test lab.
When Dan D'Agostino received the initial preprint of this review, he was concerned that this behavior indicated that the amplifier had suffered some sort of damage on its way to me from Jason Serinus. (After it had been picked up from Jason, the amplifier had been shipped to a dealer before it eventually found its way to me.) I was therefore sent a new sample of the Progression Mono (serial no. PMO100P), which had been fully checked out on the test bench, to test.
The voltage gain, input impedance, and frequency response of this sample were identical to those of the first, though the output impedance was slightly lower, at 0.32 ohms, and there was no RF noise present at the amplifier's output. And when I examined how the percentage of THD+N varies with output power, this sample clipped at 595W into 8 ohms (fig.4), which is 0.8dB higher than the 500W specification. Into 4 ohms, the clipping power was 934W (fig.5); though this is 0.3dB lower than the specification, I don't hold the wall voltage constant during these tests, feeling that this is more representative of an amplifier's behavior in a typical system. The wall voltage was 120.1V with the amplifier idling, but had dropped to 115.4V at 934W into 4 ohms.

Read more at https://www.stereophile.com/content...er-amplifier-measurements#cvirJFOXbXRKG0vd.99"

Bottom line is it may be true the customer has neither need or use for the max power these amps are capable of. But don't you think the manufacturer should supply these amps configured in a way making them capable of meeting spec? In my mind that would be a US 220 cord and have the customer have the correct feeds installed. End of rant. LOL

Interesting. There are chip amps on the market that run rings around that thing.

 

[DonH56]

Common outlets in the USA:

120 V * 15 A = 1800 W
120 V * 20 A = 2400 W (compatible with 15 A outlets)
120 V * 30 A = 3600 W (special outlet; we have some of these in our lab)

220/240 V * 20 A = 4400/4800 W
220/240 V * 30 A = 6600/7200 W (typical dryer outlet, also what my garage heater uses)
220/240 V * 40 A = 8800/9600 W (stove)
220/240 V * 50 A = 11,000/12,000 W (stove, again, electric furnace)

208/230 V are also used in various regions.

 

[Sal1950]

Common outlets in the USA:

120 V * 15 A = 1800 W
120 V * 20 A = 2400 W (compatible with 15 A outlets)
120 V * 30 A = 3600 W (special outlet; we have some of these in our lab)

220/240 V * 20 A = 4400/4800 W
220/240 V * 30 A = 6600/7200 W (typical dryer outlet, also what my garage heater uses)
220/240 V * 40 A = 8800/9600 W (stove)
220/240 V * 50 A = 11,000/12,000 W (stove, again, electric furnace)

208/230 V are also used in various regions.

But as you know. much of that power is being lost due to inefficiency and heat in Class A and A/B .

 

[FrantzM]

Some people will buy it and compare it to the Boulder or the upcoming DarTzeel .. or the usual FM Acoustics or the Goldmund Telios, tmodels in the same price range anyway... And it will have a darker background but no grit as compared to the usual <200K amplifier. It will reveal all the flaws of digital while presenting analog from of course a similarly dear turntable in a way that cannot be described ...
It will be used to drive the Wilson WAMM Master Chronosonic or perhaps the Tidal La Assoluta... Fabio will purchase a pair just to drive his subwoofers and ...

 

[Wombat]

Will Purite Audio stock them?

 

[JJB70]

I have measured up my garden and can easily fit in a a 3MW diesel generator (it's essential to leave plenty of headroom after all), fuel tank and switch board. And my analysis indicates that if I turn the volume up to 5KW and also wear industrial ear defenders (I recommend Peltor Optime III) the engine noise will be inaudible. My life won't be complete without one of these status symbols.

 

[maverickronin]

I recommend Peltor Optime III

I have a pair of those for when my pet parrot is in a bad mood.

I modded them for even more attenuation...