Are Class D amps really 5 times less powerful than A/B?

[Father Gino]

I'm always amazed at how many amps some of you guys have gone through. I've had five in 40 years. The only tube amp I had was a Musicman HD 130 which had solid state pre and a tube power. Meh, but better that what it replaced. Had one of the early SWRs, Meh. Needed an hpf on that bad boy. Had an Alembic f1x hooked up to a Stewart World. That sounded great but I was too ignorant about hpfs and maybe Alembic's own superfilter. Now I've got a Streamliner that's great. Simple to use and reminds me of the f1x in a good way but with more tone control. I think I'll just keep that until one of us breaks down. I think the Streamliner will out live me.

 

[agedhorse]

Well here goes my hat into the ring.I bought a Katana 210 sight unseen from Sweetwater because of what I read about it being class ab and having a different tone/sound from the typical class d combo..I just got done using a Mesa Bass 400+ for more than 20 years and as Im well into my 60s I thought I would downsize a bit and simplify my setup.After playing tube bass amps for well over 40 years the Katana 210 is the 1st small combo amp I have found that comes closest to that tube vibe/tone that I like.As for the claim that class ab watts are equal to class d watts 4 to 5 times as much I can only say it kinda sounds something that way to me but thats my ear,let your own ears be the judge.The Katana 210s 160 ab watts are a lot louder than you think they would be and will stand toe to toe with most 210 combos I can think of say 350 to 500 watts class d.As for you those of you doubting the engineering skills/prowess of Roland/Boss corporation.They could have chosen a variety of brown bag class d modules from various manufacturers that had more power and saved weight,were cheaper,made them more $ but they didnt.They chose tone first and felt the class ab output gave them that.Even their Katana and Nextone guitar amps are class ab.Can anyone on this site tell me of any amp companies out there that claim their amp has that great class d sound.There are a lot of them though striving to get their class d amps to sound more tube/class ab like though.The Mesa WD 800 and TT800 are a few that come to mind.

I've designed both class AB and class D models, I don't make my class D amps sound any different than my class AB models. They sound exactly the way I intend them to sound.

 

[byacey]

I'm always amazed at how many amps some of you guys have gone through. I've had five in 40 years. The only tube amp I had was a Musicman HD 130 which had solid state pre and a tube power. Meh, but better that what it replaced. Had one of the early SWRs, Meh. Needed an hpf on that bad boy. Had an Alembic f1x hooked up to a Stewart World. That sounded great but I was too ignorant about hpfs and maybe Alembic's own superfilter. Now I've got a Streamliner that's great. Simple to use and reminds me of the f1x in a good way but with more tone control. I think I'll just keep that until one of us breaks down. I think the Streamliner will out live me.

For me, it's two amps in forty years, and I still have both of them. I suppose I could have been trying to find the holy grail of bass amps, but I believe it's easier just to adjust the amp for what I want to hear. Besides, I bank the gig pay rather than constantly re-investing in new gear.

 

[mbell75]

I've designed both class AB and class D models, I don't make my class D amps sound any different than my class AB models. They sound exactly the way I intend them to sound.

Ok so if Class D power sections are lighter, cheaper to make, just as powerful and sound just as good, why would any company go with an A/B power section? Especially Boss, who's relatively new to amps and has never made a bass amp before. From listening to the President of Boss, sounds to me it was intentional and they felt they could make a better sounding amp with an A/B power section.

 

[DJ Bebop]

Ok so if Class D power sections are lighter, cheaper to make, just as powerful and sound just as good, why would any company go with an A/B power section? Especially Boss, who's relatively new to amps and has never made a bass amp before. From listening to the President of Boss, sounds to me it was intentional and they felt they could make a better sounding amp with an A/B power section.

That's a choice they made and it happens to be a choice you like the results of. It doesn't make it better or worse, it just makes it the choice you like.

 

[agedhorse]

Two reasons companies choose different approaches can relate to both a lack of experience and skill developing the technology, or for perceived marketing reasons.

Sometimes it comes down to personal preferences.

 

[rodl2005]

Hit pre amp distortion, back it up til distortion stops. Set.

While I LIKE my tube amps the best, I don't agree with you re class D not sounding good until they're turned up etc. And while my memory may be fading, I think I found the PRO series Ampegs more in line with that. More so than the PF and other class D amps
Again memory and simply, my experience is naturally affecting my view here. But I certainly found the class D amps I've used to sound good at pretty much all volume levels
As always ymmv

 

[rodl2005]

Well, because streaming sounds like absolute garbage unless you have a very nice quality DAC to run Hi-Res streaming. Even then, I'll still take vinyl. To me, its like the difference between a good old fashion tube amp and something like a Kemper modeling amp. Sure, the stream/Kemper is technically superior quality to vinyl or tube amp, but we dont hear technicalities like that. Just like a tube amp, vinyl has a depth, warmth and presence that no digital audio file can touch.

That's right... and the pertinent piece here is "to me". That's your view and you're entitled to it.
I agree in that I like all tube amps better than anything else I've heard/ used..... but that doesn't mean that it's "better", or for everyone.
I love my class D amps, wouldn't give em up for quids, same for my tube amps.
I also love playing records. They sound great. Doesn't mean that I don't like streaming music tho.

Re the loudness thingy....

Manufacturers fudge, or B.S. or use their own terminology re power.

I find it funny going to a electronics department store and seeing a bluetooth speaker that's 2 foot high (with flashing lights) with the advertising card on it stating that it's 1000 watts. When, if we're speaking RMS it's probly 25w

 

[agedhorse]

Note that "really good DACs" means absolutely nothing without considering the source material itself, the encoding (ADC and CODEC).
One "great" component does not make a great system, that's the first thing real engineers learn if they plan on remaining an engineer.

 

[rodl2005]

That's right... and the pertinent piece here is "to me". That's your view and you're entitled to it.
I agree in that I like all tube amps better than anything else I've heard/ used..... but that doesn't mean that it's "better", or for everyone.
I love my class D amps, wouldn't give em up for quids, same for my tube amps.
I also love playing records. They sound great. Doesn't mean that I don't like streaming music tho.

Re the loudness thingy....

Manufacturers fudge, or B.S. or use their own terminology re power.

I find it funny going to a electronics department store and seeing a bluetooth speaker that's 2 foot high (with flashing lights) with the advertising card on it stating that it's 1000 watts. When, if we're speaking RMS it's probly 25w

Oh, and I've been to plenty of 'parties' where, above mentioned, bluetooth speakers were the ONLY sound source, and while they weren't particularly loud(or good sounding) they were surely severely damaged way before the end of the party.

The flashing lights still worked tho

 

[bdplaid]

Very few things on Earth more entertaining to me than a snake oil salesperson going full bore on a grift. Especially how they draw (suck in) conspirators. Priceless.

A friend had a great way of handling these guys...

He'd listen to the pitch, then ask for the guy's card. Talking the card, said friend would look at it, then turn it sideways and pick his teeth with it.

 

[Doufuss]

Here's an article on burst power. Draw your own conclusions.

Measuring Burst Power | Bass Gear Magazine

 

[byacey]

While I LIKE my tube amps the best, I don't agree with you re class D not sounding good until they're turned up etc. And while my memory may be fading, I think I found the PRO series Ampegs more in line with that. More so than the PF and other class D amps
Again memory and simply, my experience is naturally affecting my view here. But I certainly found the class D amps I've used to sound good at pretty much all volume levels
As always ymmv

I'm wondering if it's speaker breakup that they find so wonderful, rather than amplifier distortion. A good amp should have relatively low distortion throughout it's dynamic range, until the onset of clipping.

 

[byacey]

For me, it's two amps in forty years, and I still have both of them. I suppose I could have been trying to find the holy grail of bass amps, but I believe it's easier just to adjust the amp for what I want to hear. Besides, I bank the gig pay rather than constantly re-investing in new gear.

Oh, I forgot about the '65 Bassman. I only used it once on a job, and put it away after that, and forgot about it.

 

[prowla]

Didn't read the entire thread, but having grown up listening to the Rolling Stones I thought that watts were a measurement of drum volume.

M. M.

And a bit of Charlie.

 

[paskisti]

Oh, I forgot about the '65 Bassman. I only used it once on a job, and put it away after that, and forgot about it.

My only experience about Fender Bassman was old 50W silver front face tube head and Fender 2x15 silver cloth cabinet. I have never played worse setup because if started to fart early and never got good sound out of it. It was night and day difference when we got Hartke Model 2000 combo for school band back in nineties.

 

[agedhorse]

Here's an article on burst power. Draw your own conclusions.

Measuring Burst Power | Bass Gear Magazine

4 different design philosophies, none of which are better or worse, and none of those examples are categorical of the amp's class, but more of the power supply and intent or byproduct.

 

[byacey]

My only experience about Fender Bassman was old 50W silver front face tube head and Fender 2x15 silver cloth cabinet. I have never played worse setup because if started to fart early and never got good sound out of it. It was night and day difference when we got Hartke Model 2000 combo for school band back in nineties.

This predates the silver faced amps by a few years, but not too much different. The 50W was adequate for some low key jobs, but a properly tuned efficient speaker box goes a long way to making the most out of those 50 watts.

 

[baxter_x]

I wish I was paid everytime someone comes up with all those myths about class D amps......
I'd be the richest man in the world.

 

[teemuk]

Here's an article on burst power. Draw your own conclusions.

Class-D amp has nice squishy sag and warmth from its dynamic clipping distortion? All-tube amp is stiff and sterilely clean?

Ain't the test results showing exactly that? You see, all sorts of conclusions can be drawn.

Personally I'd be vary of drawing too many conclusions from a very small number of samples. Another class-D and tube amp might perform in an entirely different manner, and like agedhorse pointed out, amp operating class alone can't be used to categorize how an amplifier operates under e.g. burst power or continuous loading*.

*That said, a reasonable expectation is that typical class-D audio and musical instrument amps are not designed for continuous loading at excess durations (i.e. > 1 min). Not that it would matter, we don't expect them to drive AC motors with continuous sine wave but to reproduce complex waves with moderately high crest factors.