Class D Amp Journey

[scotte1]

My mini-review on the AGD Productions Class D “The Audion” amps from my Audion thread:

“Components:

Anthony Gallo Acoustics Strada (MK I) Speakers
Anti-Cable Speaker Wires
The Audion mono amplifiers (85 wpc, Class D, “Chip in a bottle” design)
BSG Qol Signal Processor
Hattor Mini Preamplifier (passive preamplifier w/ optional, 3-level op/amp buffer/gain stage)
Emotiva and Better Cables XLR cables (connecting amps to Qol and Qol to Hattor preamp, respectively)
REL Acoustics T/5i Subwoofers (Stereo pair connected directly to The Audions – as is “the REL way”.)
Jolida tube DAC
Auris bluMe “True Hi-Fi Bluetooth Audio Receiver”
Denon DVD 2900 “Universal” Disc Player (primarily used as a transport with the DAC, and to spin SACDs directly now and then)
Beldin digital coax cable and Lifatec toslink cables to connect the DAC to the Denon and Auris, respectively.
Morrow Audio RCA interconnects to connect DAC to the Qol processor
Adcom ACE 515 power conditioner
PS Audio PowerBase (The Audions are plugged into the PowerBase)

Listening impressions:

Smooth presentation
Neutral to slightly warm overall
Holographic (great H x W x D capability)
Excellent realism with acoustic instruments, especially reed instruments
Not the last word in bass snap and low level resolution, but certainly no slouch*.

Plenty of dynamics and they play with a real sense of ease no matter how busy, loud, quiet or simple the signal it is amplifying is.

*A word about the bass slam and ability to reveal low level information (i.e., subtle details that are more buried in the recording): My observations here are very subjective and relative in nature in that my impressions are as compared to my “reference” 500 wpc Emotiva XPA-1 (MK I) Class A/AB mono amplifiers. The Emotiva’s and their 500 watts proved to be a bit more dynamic and revealing in head to head comparisons made in my main, home system. Given the disparity in available power/head room I don’t think that should come as a surprise. One surprising outcome of my listening sessions was coming to realize just how good the budget minded, “world beater” Emotivas really are. I paid about $1,800 for the pair, new many moons ago.

That said, the 85 wpc, large-brick-sized Audions are nearly the equal of the 75 pound, 500 watters in all characteristics and are better in throwing up a beyond-the-speakers sound stage.

I highly recommend these amplifies and I hope others with an interest in these amplifiers will continue to contribute to this thread.

Cheers”

[stevensegal]

[nortonkp]

Bel Canto Ref 500s are B&O ICE based amps, the Ref 600s are Hypex Ncore based amps. They adopted this technology from their Black Series. According to Bel Canto their amps got 10 dB quieter going from Tripath to ICE technology, and going from ICE to Ncore tech dropped their amps another 10dB of noise. High frequency switching noise being the biggest drawback to class D switching amps, 10 dB of noise reduction is pretty strong!

[john2213]

I’ve never experienced class D, aside from subs but I sure could be tempted by these…

Best,
-JP

Merrill Audio - Element 118 Power Amplifier Monoblocks

[Craig_Burgess]

I hadn’t either, but a year ago I succumbed to the call of the M700s.

[Palouse]

@Craig_Burgess Me too!

[Birger]

I first bought a Primare A30.7 and then I bought a Primare A34.2 and then I bought another Primare A34.2 and I still use all 3 of them in my stereo.

One A34.2 to the bass in my main speakers and the other A34.2 to the midrange/treble in those speakers.
I use the 7 channel A30.7 to my center and my 4 surround-channels.

[Serhan]

An early adopter of the NCore was Theta in the Prometheus monobolcsks at$12,000 a pair and 54.5Lbs each.
Prometheus | Theta Digital
That’s a serious power supply in there!

[aangen]

This is the inside of my NBS Universal II Amplifier.
Power supply on the left, Hypex card with specialized Class A input device on the right.
I had no sadness using it. I quite enjoyed it.

[badbeef]

They do a lot of things right. As with anything - no free lunch.

Receiving a Purifi Eval Kit tomorrow and a Ghent chassis. Should be fun!

[Gary_M]

Spectron Musician > Spectron Musician II > Channel Islands D200 mkI > Channel Islands D200 mkII >

Was pretty happy with the Channel Islands mkII, but it was replaced by the BHK 250, which was in another league. All the digital amps excelled at certain things, speed, transparency, bass response, but the top end was never that satisfying, along with a rather dry overall sound.

[davidl]

Here’s my chronology with class D amps:

2000: Spectron Musician 2 (John Ulrick’s own design). Very good sound but unreliable and insufficient protection - I was effectively a beta tester for several years
2006: Alner Hamblin SA-400 (Tripath modules). Excellent sound, reliable but became noisy
2015 to present: Primare A.60 (Primare’s own modules). Even better sound, totally reliable and bullet-proof. I cannot see any reason to change.

[nortonkp]

I have almost had too many amplifiers to count over the years! In terms of class D amplifiers I have owned:

Tripath;
Bel Canto eVo2 GenII
PS Audio HCA-2

ICE;
Bel Canto e.One S300

Hypex UcD;
Resolution Audio Opus 21 S80

Hypex Ncore;
Maranatz PM-10

The tripath amps had an almost tube like sound quality. The second generation Bel Canto with the original ICE amp technology was too dry and cold. Sold it in less than a month. Hypex’s original UcD technology was better but not great. Sold that amp in less than a year. After having a Krell Evo 2250 then, Classe CA-M300s, then a BHK 250 and finally BHK 300 mono block class AB amps, I tried class D once more. Hypex’s Ncore sounds very good indeed!

[Rudolf_Appel]

I own a NAD M33 Eigentakt, refined nCore model designed by Purifi. NAD Has it produced under license. I think Bruno Puzeys nailed it.

I miss nothing, compared to my previous amplifier it only added:

• dynamics
• precise bass
• details (I never heard before)
• precise soundstage
• value to my speakers

[jtsnead]

I started this thread don’t know why I don’t get notifications

[Serhan]

If you click the watch bell at the bottom left pulldown menu, then it will send you notifications. It may have been turned off inadvertently.

[jtsnead]

Nope it was on “watching”

[Serhan]

nothing’s landing in the spam / junk folder?

[Elk]

Perhaps try setting it to “normal,” exit the thread and the forum, then come back and reset it to “watching.”

[HanksJB]

I had what I would call a nice system back in the day. I started out in junior high with a Technics SA-300 receiver and a Pioneer PL-518 turntable. My dad donated a pair old Magnavox two way bookshelf speakers. I used then for about a year as I saved up for Phase Two. Phase two was Acculab 440 speakers for Christmas and about a week later I bought my first tape deck, a Pioneer RT-707, which is still a part of my current set up.

A couple years later I expanded, adding an Akai CS-F39 cassette deck and NEC video monitor. I upgraded my Receiver to a Sony STR-AV 580 audio/video control center and set up for expanding to video. Shortly thereafter I purchased a JVC stereo VCR (can’t remember the model, high end for its day). I then added an ADC Sound Shaper 33 EQ. This set up lasted until about 2001. I still have the Sony and EQ as well as the speakers.

My first house had a nice room on the bottom floor where I could set it all up, wouldn’t bother anyone, able to expand my CD collection and store my Vinyl. During this time and through the prior five years I had moved around a lot and various components began to fail. First to go was the NEC, tube blew. The PL-518, wish I would’ve held on to it, was next to go. The feet had come apart and I was no longer playing vinyl at home. I was DJ’ing and my partner and I had 3 Technics 1200 turntables and a half dozen cheap cd players that we used. For personal listening it was all CD’s.

When my wife built the current house we went a bit above and beyond what we really needed at the time, but with an eye on being able to do bits and pieces of expansion as needed and funds permitted. My mother in laws health began to fail and we decided to finish off the basement to provide a living are for her, effectively doubling our square footage. Prior to this I didn’t really play the stereo because it was in the main living area, and especially after having our son, their was two much vibration to truly enjoy the set up. when we agreed to finish down stairs, it was with the understanding that I would have my own space to dedicate to music/entertainment. I also made it understood that I was going to get quality components, better technology.

January 2019, about 6 months before work was completed I started check my other gear to see if everything still functioned and try to figure what might stay or go. I first move was to replace the Sony Receiver, or upgrade as the video section was rather sketchy. I purchased a Marantz SR 6013 with an eye on expanding to a nice home theater set up. I purchased about 200 feet of mid grade in wall speaker cable and HDMI cable to run in the walls before they hung the sheet rock. I hired a cabinet maker to custom fab cabinets and shelves to store my music, space for about 500 LP’s and 4300 Cd’s and other collectable odds and ends.

Next up I started listening to speakers. I was shooting for about $2500 budget. I started hearing/reading about Focal and stumbled across Greentoe. One blog I read kept pushing Greentoe for TV’s claiming that you made an offer to buy at whatever price you thought fair and they would shop it with their network of authorized dealers. I offered $2600 for a pair of Focal Aria 948, half of what they were currently selling for and they accepted.

After about a year I just wasn’t thinking I was getting all i could out of the speakers so I sold my baseball card collection and rolled that into the power upgrade. PS Audio was getting rave reviews in Stereophile, as well as all kinds of good chatter on various forums. I got a set of M700’s used, three months old, as well as a P3, one month old and a Stellar Gain Cell, 6 months old. I’m quite happy with the end result. Never really considered class A or A/B product. Not sure I need to.

I drool at the prospect getting some BHK’s, but that’ll have to be a story for another day.