Desktop Speaker Amps: Is Class AB becoming obsolete?

I write this post as an open question to the community: has Class A and Class AB speaker amps taken a backseat to Class D and Class T in the desktop environment?

Recently I contemplated buying the Emotiva BasX A-100 to power a to-be-determined set of speakers on my desktop (considering the ugly Monoliths) and I had to ask the serious question to myself if paying more for Class AB was worth it. Class D and Class T amplifiers have come a long way in sounding great, and now ‘smol’ things like the SMSL SA100 appear to have an edge in the price to performance arena. Not only does it seem like a better value for the price standpoint alone, but it also has features and conveniences like Bluetooth 5.0.

Despite this, I’m still somewhat biased and want to go with the Class AB amp. I’m not sure if I’m alone but I feel like I am stuck with yesterday’s differences between Class AB vs Class D even though I acknowledge the gap is closing or may even be non-existent for a desktop application. If I am not going to the limits of the amp, then is there really a difference any more besides one costing more while containing less features? Would there be a difference in a near field environment like a desktop?

Because I am thinking about doing it, I might have to buy a SMSL DA-8 (because I’ve heard good things about ICEpower Class D amps) and ask if Zeos would be kind enough to compare it to his Emotiva BasX to get an apples to may-as-well-be-an-apple scenario. A large part of me is also thinking that maybe I could get away with a Topping PA3 or even the SMSL SA 100 to get even more features and not miss anything.

Anyways, is Class AB becoming obsolete? I am spending too much time thinking about this because I’m obsolete? Is Class D or Class T the way to go for a desktop, near field setup? Please let me know your thoughts.

I don’t think class A/B amplification is becoming obsolete per se, but I think that miniature class D amps are gaining market share because their sound quality is catching up (if not already equalling or surpassing A/B in some cases), they do offer a strong price/performance ratio, and they simply fit better on a desk. Classes D and/or T may be what most audio amplifiers of any type are made of down the road but I think it’s too early to say A/B is obsolete.

Also, I don’t think the near-field question applies to amplification. How close you are to your speakers matters more when you’re talking about speakers. If a speaker doesn’t do near-field well, it won’t make much difference if it’s driven by A, A/B, D,… Full disclosure, I use an older Onkyo HT receiver with A/B amps in it as my desktop stereo amp because its HDMI output failed so it could no longer anchor my home theater. I also have a Micca Origain (one of those little Class D amps) that I use in my office at work. When I compared the two they sounded a little different, but it was really hard to say that either was ‘better’. The Onkyo has more power so I keep it at my home desk so that I can crank it to have room music when I’m not sitting at the desk. When I’m at work though, I still marvel at what that tiny Origain can do.

Bottom line, the choice you make should depend on what differences you perceive. Do you prefer the sound of Class A/B or Class D? That’s only a question you can answer. Then, consider things like price/performance ratio and how much physical room you have on your desk setup.

Hope this helps. Happy amp hunting!

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Thank you for the reply.

I only said near-field as I just wanted to qualify that I do not intend to cause myself further hearing loss at my desk and should not need an astounding amount of power to say go to the limits of an amp.

The title is a bit hyperbolic, but I’ve long held the bias against Class D and T. In the current day, I don’t think I can justify that bias.

I can’t compare the different classes of amps as I am a little inexperienced with amps, but I went from a 90W/channel Sony receiver to the 50W/channel Emotiva A-100 and heard a noticeable difference in sound. My music sounded “fuller”. Not sure how else to explain that, but I felt a gain in performance. It is a very heavy, well built amp and fits perfectly on a desk although a lot bigger than most desktop amps.

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I have the A-100 paired with the Elac UB5’S I’m using the schiit modi Multibitbit for a DAC when
Playing Flac files or streaming. iMO AB amps are here to stay.

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I have the monolith K-Bas as my desktop speakers mated with BIC America V1220 sub. First of all let me say I absolutely love these speakers Used nearfield. I don’t know how extreme your tastes are but these speakers satisfy my listening desires. I have used them with both an Emotiva Bas-X and the PA-1 monoblocks. In my opinion i feel i get more output and volume with the class D monoblocks. I enjoy the quality of sound through both set-ups but there is just more volume with the more powerful monoblocks. Your DAC and source material will also affect sound quality and volume. There is something to be said about component synergy. I have gone through hundreds of dollars worth of components to find the sound i like most and even then every few weeks i swap out components simply to enjoy a different sound signature. Good luck in your adventure.

Well, were the monoblocks more powerful then the basx? Then it would make sense that the more power would lead to more output and volume, regardless of the class of the amp

So I made a different post that sort of is my first step in answering this question:

I am using fairly efficient (96 dBW, 8 ohm) Klipsch towers with a Class D SMSL AD-18 and am happy with the results. Because they are efficient, I do not need to go into massive power amps to get a good volume and sound out of the towers.

But I still intend to make some changes to see what changes. Over the holidays I may build a Class A amp I have had my eyes on for a bit now to hear the differences. Will report back if I do this.


Building amps can be pretty fun if everything goes cleanly, hope it turns out great :+1:

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Thank you, looking forward to it actually. Will try to document what I am doing as DIY stuff is fun and can always use more exposure/interest in the hobby.

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That’s awesome, I have been researching different DIY projects and setting up a small work area for electronics work. Looking forward to seeing what you decide to build. A, A/B, D, none of them going away any time soon especially with so many people coming into the hobby and wanting to experience all the different sound flavors. Good luck on your build!

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