Digital Amps - Your opinions and why so few?

Hi, I'm in the market for new amps for Maggie 3.6r's and just wondered what your experiences/opinions are on digital amps.
The technology seems well developed, and the advantages seem very tangible 'on paper'. I spoke with a tech guy at Tact Audio concerning their S2150 amp, and the 'specs' are very impressive. They amps also provide the facility to replace the speaker x-over. In a 2-way speaker, you can use two digital amps and program each amp with the associated crossover parameters.
I also spoke yesterday with a real gentleman, Henry, the designer/founder of H2O digital amps. I found him by following a buzz on the apogee audio website, where people using the difficult to drive apogees are dumping off their big Krells and Pass amps, and getting in the queue for the H2O. The few people already using the H20's are raving about them.
Then of course there are the Spectron amps, though I read somewhere recently that they may be going out of business?

The point is, if this technology has matured, and these amps can compete with convential amps, and they are cheaper, lighter, give off less heat, generate higher watts from a smaller/lighter chasis, and.....wait for it....may actually sound better dollar for dollar, why don't we see more of them around?

PS - I'm considering dropping big $$$$$ on a pair of new S2150 Tact digitals, please, please talk me out of it, and tell me these amps are crap....
Probably because they are a new technology?
There are more and more popping up, but i wouldnt expect every manufacturer to jump on the craze and immediatly have a full line of digital amps out.

Give it some time. They will probably be more common than analog Solid-state
A lot of Audiogoners are going back to vinyl...does this give you a hint?
I own a Musician II and 3.6's. I have been very pleased with it's performance. I considered running two but decided to stay with one. As far as going out of business. John never made any indication to me that he was headed that way. I liked the amp so much I purchased the model 10 pre to go with it. I too spin the black circle. The digital gear mates very very well with my VPI table. Changes and advancement in technology can blend with yesterdays gear too...........
Digital amps will dominate the mid fi market and will make significant inroads in the audiophile area. It's simply a different way to design an amplifier and it has some advantages as well as disadvantages when compared to alternative designs. I suspect you'll be very happy if you go with the TACTs.
As a TacT owner you'll be very pleased with the TacT amps if you feed them directly with a low jitter digital source. Doing this, you can also eliminate the need for your upsampler(the amps upsample to 384K) and preamp. The x-over function takes some study time, but there's lots of support
on the Yahoo TacT users forum.
Just my personal experience with a good digital amp:

I owned, for awhile, a Bel Canto EVO 200.2. It was an absolutely wonderful amp for the money, with firm bass control and an amazing degree of refinement versus the Musical Fidelity Amp I had before it (a bottom of the line MF piece, the A3.2 CR). The Bel Canto was easy on the power bill and ran incredibly cool. It also was very well built and kept a very low profile in my rack.

I decided to sell the Bel Canto and go in an entirely different direction. I bought a Pass Labs X-250.
Lots of heat, chews through electricity like a fiend, weighs 100 lbs, and fills a huge portion of my Particular Basis rack. The Pass however, has proven to be the best audio purchase I've ever made, and was a major improvement over the Bel Canto in every area EXCEPT energy efficiency.

In all fairness the Pass costs multiples of the Evo's cost, and in retrospect the Bel Canto Evo 200.2 still conjures up warm listening memories. It showed my ears that digital amps can sound very good.
I have Accoustic Reality digital amps they are wonderful,very sweet sounding.They can easily compete with the large amps.
Hi Ramy, I'm glad you like the Acoustic Reality. It was a revelation to me, as well. BTW, my amp journey took me through the Pass X600 to the eAR. Now, I have moved to a new best amp ever, the H2O, another ICE powered amp, but one that is all together different, with much more power.
I will put in my usual plug for CarverPro ZR1600...about $800. Put the extra kilobucks into better speakers, and audiophile discs.
Check out the Ice Technology in the Rowland 201 and 501 amps also for another high power amazing sounding amp. If you can go with the 501 at 500watt into 8ohm and 1000watts into 4ohm. I owned MGIIIa's and 1.6, both love as much current as you can give them and lots of space off the back wall.
rowland 201 has a purer sound & darker background compare to pass X150.5. Pass however has a touch more warmth and piano note is more weighty but less details. Both goood.
ZR1600 is a good choice for planar speakers. There are several mods available for it. I compared it head-to-head with JC-1 monoblocks and it controls bass better than any amp I have heard, including the JC-1's. Here is a recent shootout:
I'll second what Ramy said about the Acoustic Reality eAR amplifier. I hate to use adjectives like "analog" or "un-digital" to describe its sound because I don't believe in these terms. But I will say that it sounds "right" and "natural", and that's about the highest compliment I can give to a piece of audio gear.

With respect to the key topic of this thread, I think that that digital amps have already grown to dominate the low-end. Just look at the plethora of receivers from the likes of Sony, Panasonic, JVC and others, and you'll be hard pressed to find one that doesn't use a switching amplifer circuit. This is not meant as knock against the technology, but it's merely a reflection of its potential for lower cost which plays into the busines model for affordable consumer gear.

The high-end market is a different ballgame altogether where demand is low, margins are high, and the consumers (though few in number) can be demanding, superstitious, and fickle. For this reason, I think there will always be a market for diversity in the high-end so that digital, linear SS amps, and tubes will continue to co-exist for the foreseeable future. As to the question of why there are so few currently, that's certianly not true in the low-end consumer market. Digital amps are only relatively scarce in the high-end, for now, because of its newness, yet I don't expect it to dominate this end of the market like it has in the low-end for the simple matter of what I noted earlier about how demanding and superstitious this market can be. To wit, the term "digital" still carries a stigma to this day that's hard to shake, whether it's wholly deserved or not.
Thanks for comments offered so far. I want to believe that a pair Carverpro zr1600 can sound better than a pair of Pass X600's, it's just difficult to digest, given their retail price difference. I'm not a hifi 'snob' and have no 'issues' with Carver amps, or Bob Carver, as some people on AG seem to have. I just don't want to go through another round of buying and selling.
Vince, I know you've been flying the flag for the H2O's, I'm sure the amp is every bit as good as you suggest. I'm worried however about buying into something that doesn't have a real track record. Also, the fit/finish looked a bit unprofessional on the photo's that Henry sent, so resale value and reliability is also a concern, that and his price has gone up $1000 on the monos, not to mention the 3 week leadtime.

I wish someone could do a head-to-head between Tact and Pass, or Carver and Pass etc. mentioned bass performance when comparing the ZR and JC1's. Were the ZR's stock or modified?...what other insights can you offer about the two amps, beyond the bass performance? I read the shootout you listed and it seemed inconclusive. Clearly one of the people was a tube fan, and didn't respond well to the presentation of the ZR, the other people seemed undecided on the relative merits of each of the two modified Carvers.

Anyone else with digital experience that could offer a side by side comparison with high end analogSS?


I have an Acoustic Reality digital amp. These amps have a conventional toriod for the power supply & ICE modules for the digital section. This amp sounds very good to me, so did the Spectron I borrowed from a friend.
I do have a Debussy CD that has some very low level room noises in the performance. I now use this as my reference resolution test CD.
The AR amp clearly re-produces the louder of the 2 backround noise incidents. Any of my Pass Aleph amps makes both easily heard.

I am a dealer for the new Flying Mole digital amps. Shown at Cedia a few weeks ago, their is a review in the current edition of Widescreen Review by Gary Altunian. For addt'l comments see and search for the review of the Von Schweikert dB99 high efficiency speakers. The writer comments on the DAD-M100 pro here as well. Affordably priced, compact in design, efficient and generating little heat, these 100watt giant killers have attracted lots of attention lately for 2ch and HT application.
See the site at or for more info
Rooze, the pics you saw must have been of his very first hand made prototype. My amps have perfect fit and finish. All the ones I've seen pictures of coming off the line are the same. I hear you on the sales lag time. There is a waiting list. As for resale, I know several people that would pay full price for my used monos.

Oxia knows I owned an Acoustic Reality, and the Pass X600. There is no doubt for anyone hearing all three, the H2O is the finest al-rounder. There are several items separating the H2O from the Acoustic Reality. For one, the H2O has an independent power supply, not borrowed from winds on the output transformer. The H2O transformer is a kilowatt.

A thousand dollar increase was necessary. The H2Oo amps are substantial amps that do not cut corners anywhere. The $4k price is way under some competitors, and equal to others. Henry offers a free trial for prospective buyers.

Perhaps I can expand a bit. A bit over a month ago I drove up to visit Henry and listen to his H20 monoblocks on his Apogee Scintilla's after hearing much of the buzz on the Apogee user forum.

You mentioned the fit and finish to look a bit unprofessional. I would respectfully disagree. Seeing them in person they are superb in fit and finish. They are not "exotic or industrial engineering state of the art" in form. Form follows function. With that being said, I can't recall off the top of my head ANY manufacturer out there that uses 3/8" thick aluminum plates on ALL sides of the unit, top, and bottom. It is a very refined and subtle look.

I was also aware of the price increase being imminent. As I understood from reading the Apogee forums, these amps were being produced for forum members at near cost as a "gift" to forum members that had interest and wanted to try them before the retail pricing was set forth. I can honestly say these monoblocks at a retail of $4K are still quite the deal. I don't say that lightly. However, I did hear the amps driving a 1 ohm load Apogee Scintilla. There is something to be said about system/speaker matching. If these monoblocks perform with other speakers equally as well as they did on the Scintilla's then it will not be long before the H20 name is common in audiophile circles. I would also go so far as to predict when a review site such as or get a listen with these monoblocks there will be much more than a 6 week wait time. Again, IF - they perform sonically with other speakers as I have heard them on the Scintillas - they will be nothing short of an amplification leader at their price point, not to mention their stout fit and finish.

As for the wait time... you may have seen the "Preamp deal of the century" thread about Supratek preamps. There is a reason there is a 6 month plus wait. Both of these designers want to manufacture a product to their exacting specifications, by hand, with their own eye. Then they test them for some hours before shipping to ensure they are as they should be. I personally wish more audio companies took this stance.
No matter how many reviews you read you will not really know how an amp would sound with your speakers, room, and source. The real virtue of the CarverPro ZR1600 (which by the way has no connection to Bob Carver) is that the cost is so low that most anyone can afford to buy one and give it a real try. Few can afford to take a flyer on a 6-grand item.
I agree with Eldartford and the AudioEngr...the Carver ZR series amplifiers are the ShizNit! LOL
Eldartford & Gmood1,

How well would the Carver match up with the Hyperion
HPS 938's (If you have ever heard them). And also, what
would you recommend for a pre amp? Do you need the use
balanced ic''s or does it need special adaptors??
Telescope_trade I haven't heard the Hyperions. I need to go up to PeteWhitleys and listen to them. I believe he bought a pair not long ago.You can use adapters. I picked up some from Radioshack for 8 bucks to use between the Carver and MiniMax tube preamp. This amplifier is just so easy to listen too. It seems to bring out the virtues of the MiniMax. I imagine it would work well with just about any decent preamp though. The amplifier doesn't suppress the music at all. If the preamp and source can keep up with the dynamic swings in the recordings. The Carver will let you hear it! The bite of the horns and the strums of string instruments are vivid and full of colour.It doesn't add artificiality. It just puts out front whatever the recording engineer wanted you to hear at that moment.Whether the singers voice or separate instruments jumping out when they are suppose to.

It is such a surprise and delite to hear something that doesn't cost an arm and a leg that performs this well.

I am using a Panasonic 45 till I decide on what I want to do with my frontend. It is a steal for the $$ with only changing the shaver PC on it.

I do feel there are drawbacks to the Hi-Freq's,but considering the price and not getting the sterile,hard presentation which is often associted with Japanwse based amps I can see how these things shall promote satisfactory sonics for an affordable price for those not having the $$ to buy anything more expensive. Speaker matching is a must as I feel they are more up to the task of driving my monitors than the 3-ways. Luckily I find the monitors just as good to listen to as the 3-ways.

Another thing to mention is that these Digital Amp modules are not expensive to manufacture which makes me wary of investing to much for them. Take away the faceplate and there is not much in the way of expense.

Just my opinion!
Telescope_trade... I, also, haven't heard the Hyperions. As Gmood1 says, the ZR1600 input is balanced (remember this is a Prosound amp) but it works fine single ended using the Radio Shack phono/rca adapter. With regard to preamps, the ZR1600 input sensitivity is adjustable.
Choices range from 0.316 to 2.45 vrms for full output (600 watts into 4 ohms) so it would be easy to match up with source electronics if you want to use a passive preamp. The ZR1600 also has volume controls, separate for both channels, which can be bypassed if you think they degrade the sound.

The only drawback is that the amp does use a fan, which makes some noise. The best solution (the one I use) is to hide the amp away in the cellar or a closet. There is also a simple mod to change the fan to a very quiet model, and, for home audio use, it's been reported that the amp does not overheat with the fan disconnected.

It is solidly built (for rough Prosound use) and has a 5 year warranty.
Thanks guys for your input! I am thinking on using
a passive pre amp, but am a little worried about using
the rat shack adaptor, and I heard that the Carver also
cannot accept spades, which means I will have to change
my speaker cables also!?
Well I'm still giving it some thought.

Thanks again!
Panny - your XR45 can sound as good as the Carver ZR1600 with the exception of bass control. This is the only edge that the ZR1600 has over it, once they are both modded anyway. This is the only way that I will listen to either one. Before mods, I feel that the XR45 really sucks, but the Carver isn't too bad stock.
The ZR1600 fan noise is easily remedied. It can also sound superb with the right mods. See this recent shootout article:
Eldartford, what was your experience with break-in on these amps? much time do they need and what kind of changes/improvement occur in the first 30 hrs or so?

Also, what do you do with speaker cables, are yours banana terminated or do you use an adaptor?

I picked up a pair of the ZR1600's and have about 5 hrs on them so far.
I'm using a Cardas banana to spade adaptor but it doesn't make a really good contact.

I shouldn't form an opinion with only a few hours on them, but my initial reaction is that these amps are very good for the money, but are not really the 'giant killers' that people are suggesting....perhaps they just need another 20 hrs or so.


Rooze...I understand that you are operating the amps bridged (1600 watts!). You should realize that each channel is operating into 2 ohms, and while the amp is built to withstand this environment, I think that fidelity is somewhat degraded relative to what it will do into 4 or 8 ohms. I suggest that you experiment with using only one stereo amp for the pair of speakers, and compare with bridged results.

In the long run, I think that you might do better to use the amps in a biamp configuration using an electronic crossover. That is what I do. One channel drives a subwoofer system, and the other the associated MG1.6.

I am not a great believer in breakin, and never performed the kind of listening (the same recording over and over again) needed to detect an effect. If they improve with use, hey...that's great. My cables are also nothing special. The sunwoofers and the woofer of the (2-way) MG1.6 are wired with generic #12 wire, with no terminations on either end. Bare wire, clampred into the binding post, which IMHO is the best way to do it unless you need to disconnect and reconnect the speakers frequently. The MG1.6 high end is biwired with deliberately small #24 wire. This gives me a 1 ohm resistance in the wire so that I don't need to use any tweeter padding resistor in the crossover. The MG 1.6 crossover is, by the way, modified with a large aircore inductor and fancy capacitors.

Of course the modification shops claim that this amp can be significantly improved, for a price. Since you have two, and really only need one, why not send one off for a mod, and see what difference it really makes. If you do go to biamp, you could use the modified amp for the high end, and stick with the stock amp for the lows.
Hopefully your running them in the bypass mode.Using the attenuators puts the amplifiers in a protection mode.It degrades the signal quite badly.

Good Luck!
AudioEng:The PC I thought brought up the performance somewhat and the synergy between speakers is paramount to getting exceptional sound.

What area's of modding have the most Impact to changing the characther?
Panny - an improved after-market power cord is beneficial. There is no "synergy" with this amp. If you have good speakers, they will sound good with this amp. This amp will drive any speaker well.

The mods that I do improve:
1)output filtering stages
2) op-amps - by eliminating 8 and replacing with 3
3) power delivery to both the remaining op-amps and Tri-path module

All of these I feel are necessary.

Steve N.
Empirical Audio
I've had two Carver ZR1600's running for about 30+ hrs now and they seemed to have leveled out as far as break-in goes. These are incredible amps for the money, but I don't think they are 'giant killers' as I've heard them referred to. I can imagine that someone with a difficult speaker load and a tight budget would benefit greatly from these amps, however, in stock form they are not SOTA sonically, at least not in my system.
I've posted a bit more information on this thread here Amps for Magnepan 3.6r since it seemed to be a more appropriate venue.
I'll get another 40 hrs on them and probably do a review.
If you are running Magnepans stock ,you will never hear what any amplifier is capable of with these speakers IMHO. You are running great multi thousand dollar gear with 50 dollar crossovers.There's so much more information in the music you aren't hearing with these speakers. There's no way to explain it unless you have experienced it. I hope it works out for you.
Gmood1...I've done the fuse/attenuator bipass mod and have about $1400 worth of caps and alphacore inductors which I'm getting ready to install, along with an internal rewire and relocation of the internal x-over to a new external box. I'm hoping things sound good when it's all over!

That's great!! You should hear a tremendous improvement in depth,bass and transparency.
Good luck with the mods.