• 03-15-2012, 11:24 AM
    Feanor
    Yet another high-end class D amp
    Yet another high-end class D amp announced:

    MBL introduces the C15 Mono-Power Amplifier | AVguide ...

    http://www.avguide.com/sites/next-te...Mono%20Amp.JPG

    MBL website; (navigate to Corona Line)

    There are now plenty of relatively (or very) high-end class D amps out there. Most makers are cagey about calling them "class D", usually referring to them as "switching amps" or vaguer terms, on account of snob reviewer condescension. A few examples out there ...
  • 03-15-2012, 11:54 AM
    E-Stat
    Quote:

    Originally Posted by Feanor View Post
    Yet another high-end class D amp announced:

    Don't forget the Mark Levinson 53.

    What is unusual about this design is moving the switching frequency up from around 400 khz to 2 Mhz.
  • 03-15-2012, 12:58 PM
    Feanor
    Quote:

    Originally Posted by E-Stat View Post
    Don't forget the Mark Levinson 53.

    What is unusual about this design is moving the switching frequency up from around 400 khz to 2 Mhz.

    Gorgeous (looking) amp as you'd expect from Mark Levinson ...

    http://marklevinson.com/images/prodp...ront-Panel.jpg

    If I'm not mistaken, class D design that shift the switching frequencies are according to various schemes are becoming the fairly common these days. But I suppose sophistication in this respect is a differentiator of pricier equipment.
  • 03-15-2012, 01:05 PM
    Ajani
    There's also the Theta Prometheus monblocks $12k for the pair, using the new Hypex NC1200 class D module:

    http://hometheaterreview.com/images_...s-mono-amp.jpg

    Theta Digital Releases Prometheus Monobloc Amplifier
  • 03-15-2012, 01:19 PM
    E-Stat
    Quote:

    Originally Posted by Feanor View Post
    Gorgeous (looking) amp as you'd expect from Mark Levinson ...

    Looks good under the hood, too. :)

    Exposed

    Quote:

    Originally Posted by Feanor View Post
    ...class D design that shift the switching frequencies are according to various schemes are becoming the fairly common these days

    Hmmm. That is not my understanding. From the last link, there is commentary about linking multiple bridges to achieve the higher sample rate. Along with the increased rate comes additional RFI shielding needs, too.
  • 03-15-2012, 02:51 PM
    Feanor
    Quote:

    Originally Posted by E-Stat View Post
    Looks good under the hood, too. :)

    Exposed

    Hmmm. That is not my understanding. From the last link, there is commentary about linking multiple bridges to achieve the higher sample rate. Along with the increased rate comes additional RFI shielding needs, too.

    I don't recall all the variable switching frequency references I seem to recall, however NuForce seems to say something like it ...
    Quote:

    Originally Posted by Nuforce
    NuForce's amplifier technology is based upon the principle that a power oscillator can be modulated by an audio signal so that it produces an amplified audio signal obtained with a reconstruction filter, without the bandwidth limitation of a fixed frequency carrier-based conventional PWM control. It uses analog modulation technique and close-loop control systems. Therefore NuForce refer to its audio amplifier as Analog Switching Amplifier.

    Anyway Levinson talks about their proprietary technology ...
    Quote:

    Originally Posted by Mark Levinson
    The Nš53 removes switching noise without affecting the audio with the introduction of the new patented and proprietary Interleaved Power Technology (IPT) which, among other things, raises the switching frequency of the Nš53 to an extremely high 2MHz ...
    The Nš53 has also overcome the “dead band” problem. Dead bands are silent gaps in the audio output, created when the output devices driving the positive half of the signal and the negative half of the signal are both turned of ... The Nš53, on the other hand, was designed using a patented technology that allows both sets of output devices to be on simultaneously for short periods

    This is all interesting and goes to justify the definitely high-end, $25.000 price. Considering that $600 class D's sound pretty decent, the 42x price tag might be an example of hyper-diminishing returns.
  • 03-15-2012, 03:55 PM
    E-Stat
    Quote:

    Originally Posted by Feanor View Post
    Anyway Levinson talks about their proprietary technology ...

    I suspect that what's really different is addressing the bandwidth limits of the power MOSFETs. Since the modulation occurs in the analog world, the outputs are now dealing in the AM band.

    Quote:

    Originally Posted by Feanor View Post
    ...the 42x price tag might be an example of hyper-diminishing returns.

    Or recognizing the potential of the concept. Similarly, I find there is nothing inherently wrong with digital recordings - the limitations are shaped by the frequency and word size decisions. I find a parallel with switching amplifiers. Getting the filter noise further out a couple of octaves is a logical progression for improving the technology.
  • 03-16-2012, 06:15 AM
    Ajani
    I am excited to see more hifi manufacturers embracing class d amps. It will be interesting to see the kind of hifi available 5 years from now as class d and streaming audio gain even wider acceptance in the hifi community. Imagine a product like the Naim UnitiQute, but with 300 watts of class d power instead of just 30 watts of class b. Even more interesting if the signal stays digital up to the last moment like a NAD M2.
  • 03-16-2012, 07:06 AM
    Feanor
    Quote:

    Originally Posted by Ajani View Post
    I am excited to see more hifi manufacturers embracing class d amps. It will be interesting to see the kind of hifi available 5 years from now as class d and streaming audio gain even wider acceptance in the hifi community. Imagine a product like the Naim UnitiQute, but with 300 watts of class d power instead of just 30 watts of class b. Even more interesting if the signal stays digital up to the last moment like a NAD M2.

    The NAD M2 is pretty sweet; I'd trade my set up any time for one ...

    http://nadelectronics.com/img/img.ph...-Front.jpg/640

    Taking it a step further is the Lyngdorf TDAI 2200 that is not only all digital but also has room correction and crossover ...

    http://www.lyngdorf.com/images/stori...ilver-side.jpg
    http://www.lyngdorf.com/images/stori...lver-front.jpg
    http://www.lyngdorf.com/images/stori...I2200-back.jpg
  • 03-16-2012, 07:29 AM
    Ajani
    Interesting point about the room correction, I was planning to edit my post to mention DSP. Since DSP is a major advantage of going all digital.

    Speaking of NAD. They have another all digital amp out for just less than half the price of the M2. Still not cheap, but I believe it is a sign that NAD intends to go all digital for their entire product line, eventually.
  • 03-16-2012, 07:50 AM
    Feanor
    Quote:

    Originally Posted by Ajani View Post
    Interesting point about the room correction, I was planning to edit my post to mention DSP. Since DSP is a major advantage of going all digital.

    Speaking of NAD. They have another all digital amp out for just less than half the price of the M2. Still not cheap, but I believe it is a sign that NAD intends to go all digital for their entire product line, eventually.

    Wow! I presume you're talking about the C392DD. I hadn't heard of it before. This is a step in the right direction. Apart for class D amp stages, DSP including EQ has been for several years in AV receivers-- about time the concept can to stereo amps.

    I like the modular options for the C390DD, especially the HDMI input. (This concept is something Accuphase has offered for years that makes just too much sense.)

    http://nadelectronics.com/img/img.ph..._FRONT.jpg/640
  • 03-16-2012, 09:01 AM
    blackraven
    As an owner of a Class D Audio amp I feel that there is no reason for a Class D amp to cost thousands of dollars. Manufacturers most be drooling at the profit margins these amps have. I think that we are seeing the beginning of the Class D boom!
  • 03-16-2012, 03:32 PM
    harley .guy07
    Quote:

    Originally Posted by blackraven View Post
    As an owner of a Class D Audio amp I feel that there is no reason for a Class D amp to cost thousands of dollars. Manufacturers most be drooling at the profit margins these amps have. I think that we are seeing the beginning of the Class D boom!

    I completely agree, I see no reason for these to cost that much either seeing that the power supply's only need to be a fraction of the size of a class A/B or class A to make the same amount of power do to the efficiency of these designs. I also have a Class D Audio amp and really like what it does in my system. I do think this is a small view into the future of audio and I for one so far have been impressed in the direction it is going for the most part.
  • 03-16-2012, 05:40 PM
    Ajani
    Gentlemen, I don't think it's reasonable to compare the prices of Class D Audio amps, which are meant to be affordable excellence, with the prices of products meant to be all out assaults on state of the art. The best is always ultra expensive. Whether the difference in quality is worth the additional cost is purely subjective, and that decision must be left to the potential purchaser.
  • 03-16-2012, 06:11 PM
    harley .guy07
    I understand what you are saying but I also see these companies using their name and reputation in order to price their components ay higher levels which I know most high end companies do I just like to see when companies go the extra step to make things attainable for the common working audiophile.
  • 03-16-2012, 08:13 PM
    Ajani
    Quote:

    Originally Posted by harley .guy07 View Post
    I understand what you are saying but I also see these companies using their name and reputation in order to price their components ay higher levels which I know most high end companies do I just like to see when companies go the extra step to make things attainable for the common working audiophile.

    Fair enough. I see lots of different players in the hifi market, some cater to the common working audiophile, others to the ultra wealthy and others to everyone in between. I just see them as different options to suit all budgets.
  • 03-16-2012, 08:16 PM
    Ajani
    Quote:

    Originally Posted by Feanor View Post
    Wow! I presume you're talking about the C392DD. I hadn't heard of it before. This is a step in the right direction. Apart for class D amp stages, DSP including EQ has been for several years in AV receivers-- about time the concept can to stereo amps.

    I like the modular options for the C390DD, especially the HDMI input. (This concept is something Accuphase has offered for years that makes just too much sense.)

    http://nadelectronics.com/img/img.ph..._FRONT.jpg/640

    Yep. That's the one. I'm sure NAD will eventually have an entire range of digital amps. I might have to give NAD another chance when that happens.
  • 03-17-2012, 05:21 AM
    Feanor
    Quote:

    Originally Posted by E-Stat View Post
    Quote:

    Originally Posted by Feanor
    ...the 42x price tag might be an example of hyper-diminishing returns

    Or recognizing the potential of the concept. Similarly, I find there is nothing inherently wrong with digital recordings - the limitations are shaped by the frequency and word size decisions. I find a parallel with switching amplifiers. Getting the filter noise further out a couple of octaves is a logical progression for improving the technology.

    Doubtless it's a good thing that the well-heeled will sponsor the advancement of the state of the art. That is regardless of whether the actual sound difference is huge or slight. For my part, I'm constrained to wait 'till the high rollers have been skimmed and the recent SOTA has tricked down to the masses.
  • 03-17-2012, 08:10 AM
    blackraven
    When I look at what is inside a digital amp and how little they actually weigh, you have to wonder about the cost. For example, the Nuforce Model 9 mono blocks weigh just a few pounds an they cost $5K a pair. I understand about research and development costs but I bet the profit on that is 60-75%. Years ago I worked for a electronics firm that made the computers that do all the graphic's for TV and I saw the mark up on the parts. In some cases it was 1000%.

    And looking at all those fancy cases for the digital amps posted in the pictures of this thread, I would have to say that that is a large portion of the cost. In talking with Frank Van Alstine about his new cases for his new FET Valve gear. He raised the cost $500 for the new silver cases from the old black cases. And the new ones are not that fancy!
  • 03-17-2012, 09:13 AM
    Feanor
    Quote:

    Originally Posted by blackraven View Post
    When I look at what is inside a digital amp and how little they actually weigh, you have to wonder about the cost. For example, the Nuforce Model 9 mono blocks weigh just a few pounds an they cost $5K a pair. I understand about research and development costs but I bet the profit on that is 60-75%. Years ago I worked for a electronics firm that made the computers that do all the graphic's for TV and I saw the mark up on the parts. In some cases it was 1000%.

    And looking at all those fancy cases for the digital amps posted in the pictures of this thread, I would have to say that that is a large portion of the cost. In talking with Frank Van Alstine about his new cases for his new FET Valve gear. He raised the cost $500 for the new silver cases from the old black cases. And the new ones are not that fancy!

    Speaking of mark-up, Frank is a crotchety old guy but he's not stupid. I think Frank feels his equipment has long been a bit under priced relative to competition, (i.e. domestic makers). He feels that the new face plates are good excused to raise prices We established in earlier thread that fancy custom face plates could be purchased by OEMs for about $50.
  • 03-17-2012, 06:27 PM
    frenchmon
    I sat and listened to these for a few hours....Bel Canto REF500M Digital Mono Amplifier at my dealers house. 250 watts each.

    http://www.soundstage.com/equipment/...f500m_854w.jpg

    They where driving the Bel Canto DAC 3.5 VB MKll

    http://www.belcantodesign.com/images/dac3_5.jpg

    With the Bel Canto VBS1 Power Supply

    http://www.belcantodesign.com/images...One_angled.jpg

    And it was connected to a Apple imac with an external hard drive used as his digital music server with what seemed like goo-gobbs of musical selections.

    http://www.productwiki.com/upload/im...le_imac_20.jpg

    And the speakers where Golden Ear Triton Towers

    http://www.thestereoshop.com/assets/...itonPair_1.png

    Now I've listened to this system before, but have never really sat and did some critical listening for such an extended period. Well this time I have a very favorable impression of the speakers. I had already been sold on the Bel Canto and may get one of their DAC's but the speakers really shined this time after really listening to them.

    Oh and the Digital amps??? Unbelievable.
  • 03-18-2012, 08:10 AM
    cackalacky
    Quote:

    Originally Posted by harley .guy07 View Post
    I completely agree, I see no reason for these to cost that much either seeing that the power supply's only need to be a fraction of the size of a class A/B or class A to make the same amount of power do to the efficiency of these designs. I also have a Class D Audio amp and really like what it does in my system. I do think this is a small view into the future of audio and I for one so far have been impressed in the direction it is going for the most part.

    So which manufacturers are out front with bang-for-the-buck Class D amps?
  • 03-18-2012, 08:27 AM
    frenchmon
    Quote:

    Originally Posted by cackalacky View Post
    So which manufacturers are out front with bang-for-the-buck Class D amps?

    Well...I can tell you, the Bel Canto aint cheap! But your performance will be Reference Quailty!
  • 03-18-2012, 10:07 AM
    blackraven
    Quote:

    Originally Posted by cackalacky View Post
    So which manufacturers are out front with bang-for-the-buck Class D amps?

    Class D Audio-

    Class D Audio Home page
  • 03-20-2012, 09:54 PM
    Ajani
    To add to the list:

    Peachtree Audio's flagship Integrated The "Grand Integrated Amplifier" produces 400 watts of Class D for $4,295:
    http://www.peachtreeaudio.com/media/...ated-front.jpg

    Grand Integrated Amplifier - Asynchronous USB DAC | Peachtree Audio

    Also the entire new Peachtree line; Decco65, Nova125 and Nova Power amp now use class D amplifiers.