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

[Real Soon]

All I know is, my 450W-at-8-ohms (class D) Quilter BB800 has never been remotely challenged to be set above about a 6 on the gain and volume controls each (with very mild EQ, no big boosts) with a well-gainstaged signal from basses never far from "average" hotness of output. This is thru a 1x12 cabinet, for reference on speaker surface area. That's less than 60% of the amp's overall output power (haven't measured the RMS of it at various settings, so this is very fluffy) at that setting, and that's in settings where I'm playing with not IEMs, but straight-up ear plugs.

I know there's "tube watts" and "T.C. Electronic watts" heh, but class D watts are in line with the power amp designs of all manner of solid-state builds. The preamp can be a different story as it's a separate circuit, be it a clean-yet-dirty-when-pushed transformer thing like Quilter amps or a straight-up tube preamp (I gigged and did enjoy a GK Fusion 500 hybrid amp).

And as noted before, amp wattage is one of several components of a given rig's total output. Class D amps don't intrinsically lack in what they contribute to that overall output by any means.

 

[Grinderman]

On the tube thing, I can't argue. But this depth thing with records…balderdash and poppycock.

One great audio experience I'll never forget, from about 30 years ago, is listening to Metal Box on a tube McIntosh system at a small hangout. I don't recall what turn table and speakers the host was running, if I even noticed because it was a dark room and it sounded so good I just wanted kick back and enjoy.

 

[Ethereal Thorn]

I know, but for lack of a stickie or a really good answer to this and the "heft" comparison here we go again.



Wasnex, can you compare/contrast your amps with regards to transient delivery? And, is there a standard measurement for this that amps can be contrasted with? I see these threads (and others) and for me, still can't really get the answers I'm looking for but I think I know better what the question is: how do amps handle transients, and you hit on this in your post above.

For example, I a/b tested a Mesa Subway D-800 with a GK Backline 600. Since I was in a store I couldn't unleash a volume war, but, using the same speaker I noticed that even at lower volumes the GK seemed to produce louder transients, while the Mesa felt compressed. I haven't seen this explained as of yet.

As for the "a watt is a watt" statement - good grief. HP is HP, but it's torque that gets you moving, and there's a reason why a v12 is in a Lambo and a straight six is in a Peterbuilt. My point is, different amps deliver that power in different ways - so it's not so much the wattage delivered, but how it's delivered, if that makes sense.

Much thanks to you and Agedhorse and Passinwind and many others who tolerate ignoramuses like me who struggle to articulate themselves about this.

Raz

Different taper on the gk amps they tend to have less travel before reaching max values on their pots in my experience

 

[JimmyM]

One great audio experience I'll never forget, from about 30 years ago, is listening to Metal Box on a tube McIntosh system at a small hangout. I don't recall what turn table and speakers the host was running, if I even noticed because it was a dark room and it sounded so good I just wanted kick back and enjoy.

I think it's just because Johnny Rotten has such a soothing voice

 

[Grinderman]

I think it's just because Johnny Rotten has such a soothing voice

At face value it does seem weird. I'm pretty sure it was more about what the warmth of the McIntosh did for the sounds of Levene and Wobble and how the sound filed the space.

 

[agedhorse]

I would argue that. I made some digital copies of a vinyl record and found that those that profess to have golden ears couldn't differentiate between the original and the digital copy.

Don't let facts get in the way of an industry's passion and pizzazz

No it doesn't. Digital means that the "information" (or "signal") is represented by numbers. The numbers don't have to be 1s and 0s. Of course in practice if the numbers are going to be transmitted or stored electronically they will end up as a series of on and off states, but digital audio processors are operating at a numeric level, not an on/off level. Given enough paper and ink you could take the digital data from an audio CD and print it out on paper as a series of base 10 numbers, transport the paper copy somewhere, and then scan the data back into a computer, and at all points in that process the audio data would still be digital.

If you read farther, you will see that he's addressing that the series of 1's and 0's (level states) are directly visible as an analog signal without the need for any computational mechanism.

 

[logdrum]

Well - the threads were not so hot for a while. We are back in business.

A watt is nut a wut

 

[teemuk]

It's funny that now that class-D is becoming the new norm of amplification people start to attribute traits to nostalgic class-AB amps that they allegebly didn't possess before popularity of class-D.

Formerly it was the nostalgic tube amps only but now it seems also class-AB amps have this musical clipping and more "muscle" than other equally rated amps. So times change...

It's like class-A vs. AB, SS vs. tube, analog versus digital or whatever again. Why not realize that this all is revealed in a video that is really just thinly veiled marketing of someone's newest product? Of course there will be any kind of pseudoscientific technobabble to emphasize it's superioty in order to make people BUY this new stuff.

There are known reasons why such and such amps have more gradual clipping characteristics than others, a certain "tone", certain dynamics, more loudness at given power ratings and et cetera. Unfortunately the video practically discussed none of that as the technical aspects would be over the top for average potentional customer and would not show any superiority in favour of certain types of devices or operating classes. And that WOULD NOT SELL.

 

[Topkat13]

I think it's more like 4.97 times.

 

[nnnnnn]

If you read farther, you will see that he's addressing that the series of 1's and 0's (level states) are directly visible as an analog signal without the need for any computational mechanism.

I read his whole post, but was responding just to his definition of "digital". I realise there is additional context in the post, but nevertheless given "digital" is pretty much universally presented as the alternative to "analogue" I would still say that that definition is incorrect.

 

[prowla]

In summary:
1. Switching is not digital.
2. A Watt is not a measure of volume.

 

[gazzatriumph]

Remember all the fuss about TC Electronic power ratings, I've had my RH750 and two RS210 now for 7 years gigged many times, no GAS for anything else, it's loud, sounds great never turned up above half volume and very easy to carry about, I don't care what the Watts are it does its job.

 

[baxter_x]

When done well, few if any can tell the difference in double-blind testing.

To me it's impossible to tell the difference and I simply can't believe those who say they can hear it.

 

[baxter_x]

What sucks about that, is that Class D amps don't start to open up til you're over halfway on the master. They're weak and frail sounding til then. So, there's that sweet spot on Class D amps, just like everything else, where you get the best product the amp can give you. Little more, bad. Little less, frail.

That's because the earth is flat.

....so much BS in a single thread deserves a reward

 

[5StringBlues]

Hi I'm troy McClure! You may remember me from such driver's educational films as Alice's adventures through the windshield glass and the decapitation of Larry Leadfoot.

 

[baxter_x]

This thread is a laff riot! We've been exposed to these types of amps for decades now and still the myths persist.

That drives me crazy!

 

[drumvsbass]

Ask yourself which is louder, an Ampeg PF-350, or an Ampeg SVT? By how much, is your answer.

 

[teemuk]

Ask yourself which is louder, an Ampeg PF-350, or an Ampeg SVT? By how much, is your answer.

Through same 8x10" cab both are sufficiently loud that folks find no need to test their headroom limits under any practical circumstance.

 

[BassyBill]

Almost all modern music studios record audio digitally rather than to tape. Unless you're only listening to records recorded at least 20 years ago, you're probably listening to a record whose audio has gone through at least one A/D - D/A conversion. So it really comes down to sample rate and bit depth staying above the Nyquist frequency, and compression/reduction of the final product (FLAC vs MP3, etc.).

Note that I prefer vinyl, and have a nice setup and a sizable record collection. But I mostly do it for the large format physical aspect of the media and the intent to browse the artwork, lyrics, credits, etc., while listening to the entire record in one sitting. As the meme goes, I enjoy both the expense and inconvenience. It doesn't actually sound better than well mastered lossless digital audio.

It's so refreshing to see some plain common sense comments about vinyl, in contrast to the usual "audiophile" mysticism BS about how much greater it sounds than digital media. Personally, I don't miss listening to scratched, noisy, warped, dusty or plain worn out LPs at all, or shellac 78s / wax cylinders. Gimme HQ streaming played through modern high quality gear every single time.

 

[teemuk]

Oh, and when asked about the differences the Roland representative could have also stated the only truthful fact, which is that class-AB and class-D merely describe how output devices operate, which by itself indicates nothing specific about the amplifier's performance or overall characteristics... but where's the fun of that?

And for the parallel topic, I also agree that preference for vinyl is - at least for me - related to other factors than its supposed quality and warm analog tone. Cover art, physical feel of the recording as a material object, the "ritual" of putting the record on plate and dropping the needle, and so on. The supposed downgrade of this "digital" media just reflects modern attitude towards music. It's just disposable, pretentious, calculated, overproduced product for ADHD generation that enjoys it's fifteen minutes of fame at some streamed media platform only to be obsoleted the following day by another similar pile of unmemorable turd. Why even care about audio quality?