That sounds like a job for a well set up compressor rather than any particular amp topology.
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Class D vs Class A or A/B
- Thread starter MichiganMadDog
- Start date
That sounds like a job for a well set up compressor rather than any particular amp topology.
Example:
Bass guitar with battery driven on board electronic.
The battery provides full headroom with 9 Volt.
The signal transients are free from clipping.
The battery is exhausted and provides only 3 Volt.
The signal is heavy distorted. The signal sounds louder to the ears.
Translated into average amp power it is 1/10.
My opinion.
It is never possible to point out a general rule/formula for all situations.
Each scenario to be explained needs it's own consideration.
Some folks are trying to divide in black or white.
There are a thousand of different gray colors out there.
Bass guitar with battery driven on board electronic.
The battery provides full headroom with 9 Volt.
The signal transients are free from clipping.
The battery is exhausted and provides only 3 Volt.
The signal is heavy distorted. The signal sounds louder to the ears.
Translated into average amp power it is 1/10.
My opinion.
It is never possible to point out a general rule/formula for all situations.
Each scenario to be explained needs it's own consideration.
Some folks are trying to divide in black or white.
There are a thousand of different gray colors out there.
ThisBass, one of the claims that you seem to be making is that Class D amplifiers are not capable of continuously supplying their RMS rated output power, whilst high quality AB amplifiers have no problem doing this. Is this a correct interpretation of what you are saying? A recent BGM test of the Class D GK MB800 showed that it was capable of producing its rated output power.
I am unsure how to interpret the statement that "Class D sounds more detailed with more clearness". That would imply that Class D has less distortion than AB. Is that correct?
FWIW, I am hesitant to make broad generalizations about the sound and performance of amplifier classes (A/AB/D), rather than specific implementations of each class of amplifier. What I mean is that not all Class AB amps or all Class D amps are the same. Some are better/worse than others.
I am unsure how to interpret the statement that "Class D sounds more detailed with more clearness". That would imply that Class D has less distortion than AB. Is that correct?
FWIW, I am hesitant to make broad generalizations about the sound and performance of amplifier classes (A/AB/D), rather than specific implementations of each class of amplifier. What I mean is that not all Class AB amps or all Class D amps are the same. Some are better/worse than others.
There's also another issue here that the class D, class A/B conversations never seem to touch upon, and that is the power supply topology. When are talking about class D, as it applies to the modern micro bass heads, we are generally talking about an off the shelf class D amp that has been mated to a SMPS. On the other hand, most people talking about class A/B are typically referring to a class A/B amplifier that is mated to a more traditional transformer based power supply.
So really, IMO, these threads debating the merits of either topology also need to include a discussion on how the various types of power supplies affect the overall feel and tone of your amplifier. We did some experimenting using a few different switch mode power supplies in the Valkyrie and I can say that in my experience, there is definitely a difference in how the amplifier behaves and sounds based on the power supply method used to feed the amplifier section. In the end, we stuck with a heavy toroidal transformer, not because it was "better", but because I preferred the amp, as a whole, with that type of power supply. It's kinda of like comparing stainless strings to nickel strings. Sure they both do the same thing and your bass still sounds like your bass, but there are differences there that are easy to perceive and people will logically choose one over the other based on personal preferences.
So really, IMO, these threads debating the merits of either topology also need to include a discussion on how the various types of power supplies affect the overall feel and tone of your amplifier. We did some experimenting using a few different switch mode power supplies in the Valkyrie and I can say that in my experience, there is definitely a difference in how the amplifier behaves and sounds based on the power supply method used to feed the amplifier section. In the end, we stuck with a heavy toroidal transformer, not because it was "better", but because I preferred the amp, as a whole, with that type of power supply. It's kinda of like comparing stainless strings to nickel strings. Sure they both do the same thing and your bass still sounds like your bass, but there are differences there that are easy to perceive and people will logically choose one over the other based on personal preferences.
Maybe but even a under-sized line frequency power supply will sound bad compared to a properly spec'ed SMPS.
Sorry, but I decided to hang out from the discussion.
There are two reasons to do it.
1) My weak English.
2) I don't know each Class D amplifier. I know only my own Powersoft very well, and I have some information I discussed with sound engineers and Class D amp users .
Normally the amplifier's ability to provide the rated power for a time duration of many seconds or minutes is treated as a quality criteria.
Folks normally argue, I want the "continuous" watts I paid for.
Another example.
An imaginary amplifier can provide the rated power for 3 seconds.
Try to imagine the way how you will arrange this demand with your bass guitar exhausting the full rated power for 3 seconds.
Try to imagine if there is a possible way to exhaust full rated power from conventional class AB for a duration of 10 seconds.
For example, this "imaginary" conventional AB provides full power for 5 minutes or even longer...
[Invalid or Expired Link Removed]
Still to come, transients.
Does anybody know the EIAJ recommendation?
My Powersoft amp output ratings are specified for EIAJ
EIAJ
As far as I know the letter "J" indicates Japan.
EIAJ - Electronic Industries Association of Japan
Funny thing:
The Italian engineers speced my amplifier by Japanese recommendations ....
My Powersoft amp output ratings are specified for EIAJ
EIAJ
As far as I know the letter "J" indicates Japan.
EIAJ - Electronic Industries Association of Japan
Funny thing:
The Italian engineers speced my amplifier by Japanese recommendations ....
switch mode power, will keep landfills in business.
class d is efficient and keeps down heat and overall size.
the built in thermal protection on most off the shelf chips, seems to be annoying. Having a amp shut down in the middle of a show is just crap stupid. Its happened to me so im biased.
It has alot to do with the engineering and manufactures keeping things low cost. And low cost designs haunting end users in the end.
There is a thermal limit to the actual chips, and thinking that we should have progressed since the 70's. I owned plenty of 2ohm stable amps. which use ancient cheap heatsinks and ancient output transistors. And lasted many times over these horror storys read here about brand new amps dying within the first 3 months of there lifetime.
A class AB amp Using modern high power transistors, with a generous heatsink and a well designed ventilated case. Coupled with a beefy iron power supply.
Will blow the crap out of some lightweight classD amp, being 2ohm stable and ready to last for ages without filling landfills.
im sorry life less noisy preamps with bells and whistles, and thermal failures at 4ohms just seems like a joke to me.
actually they are a joke, and the jokes on you when that red light comes on and no sound comes out your amp.
......
class d is efficient and keeps down heat and overall size.
the built in thermal protection on most off the shelf chips, seems to be annoying. Having a amp shut down in the middle of a show is just crap stupid. Its happened to me so im biased.
It has alot to do with the engineering and manufactures keeping things low cost. And low cost designs haunting end users in the end.
There is a thermal limit to the actual chips, and thinking that we should have progressed since the 70's. I owned plenty of 2ohm stable amps. which use ancient cheap heatsinks and ancient output transistors. And lasted many times over these horror storys read here about brand new amps dying within the first 3 months of there lifetime.
A class AB amp Using modern high power transistors, with a generous heatsink and a well designed ventilated case. Coupled with a beefy iron power supply.
Will blow the crap out of some lightweight classD amp, being 2ohm stable and ready to last for ages without filling landfills.
im sorry life less noisy preamps with bells and whistles, and thermal failures at 4ohms just seems like a joke to me.
actually they are a joke, and the jokes on you when that red light comes on and no sound comes out your amp.
......
switch mode power, will keep landfills in business.
class d is efficient and keeps down heat and overall size.
the built in thermal protection on most off the shelf chips, seems to be annoying. Having a amp shut down in the middle of a show is just crap stupid. Its happened to me so im biased.
It has alot to do with the engineering and manufactures keeping things low cost. And low cost designs haunting end users in the end.
There is a thermal limit to the actual chips, and thinking that we should have progressed since the 70's. I owned plenty of 2ohm stable amps. which use ancient cheap heatsinks and ancient output transistors. And lasted many times over these horror storys read here about brand new amps dying within the first 3 months of there lifetime.
A class AB amp Using modern high power transistors, with a generous heatsink and a well designed ventilated case. Coupled with a beefy iron power supply.
Will blow the crap out of some lightweight classD amp, being 2ohm stable and ready to last for ages without filling landfills.
im sorry life less noisy preamps with bells and whistles, and thermal failures at 4ohms just seems like a joke to me.
actually they are a joke, and the jokes on you when that red light comes on and no sound comes out your amp.
At age 56, I sure like the idea of a lightweight amp, and as much as I like that idea, I choose to schlep a 50 pound Crest CA9 power amp. And guess what my backup power amp is? It's another Crest CA9 (even though I have never had to use the backup....I like knowing it's there just in case).
Yeah, it's heavier gear, but I like the feeling of having a high confidence level that the gear will perform continuously throughout the entire gig. I like that feeling more than the feeling of carrying a lightweight amp. Personal choice, of course!
switch mode power, will keep landfills in business.
class d is efficient and keeps down heat and overall size.
the built in thermal protection on most off the shelf chips, seems to be annoying. Having a amp shut down in the middle of a show is just crap stupid. Its happened to me so im biased.
It has alot to do with the engineering and manufactures keeping things low cost. And low cost designs haunting end users in the end.
There is a thermal limit to the actual chips, and thinking that we should have progressed since the 70's. I owned plenty of 2ohm stable amps. which use ancient cheap heatsinks and ancient output transistors. And lasted many times over these horror storys read here about brand new amps dying within the first 3 months of there lifetime.
A class AB amp Using modern high power transistors, with a generous heatsink and a well designed ventilated case. Coupled with a beefy iron power supply.
Will blow the crap out of some lightweight classD amp, being 2ohm stable and ready to last for ages without filling landfills.
im sorry life less noisy preamps with bells and whistles, and thermal failures at 4ohms just seems like a joke to me.
actually they are a joke, and the jokes on you when that red light comes on and no sound comes out your amp.
You don't tell in your profile anything about the actual gear.
But I assume your actual "conventional" amp will clip a very very lot of portion of transients, probably not audible of course.
Be careful to tell anybody you are always at the clean side sounding area with your amp.
Don't tell anybody you have got "Headroom"
Of course I don't know your sound preference ....
full dynamik and clean? sustained? distorted?
"The master is at noon"
"The sound is powerful and clean"
"The Pre Gain is at 11:00"
"I never needed to crank the amp"
"I never needed the full power of the amp"
"... ????"
The CA9 just kills with bass and I can totally understand why you would be willing to cart one around, but while it may be my favorite power amp for bass, I must admit that I sure as heck wouldn't be willing to cart two of them to a gig just to have a backup... Well done, Sir!
Some years ago the landfills were full with iron from transformers.
Separated into iron and copper.
And carry on until all the old inefficient transformers are all gone ...
Can't say that I've ever had an output transformer ever go bad in any amp I've owned in over 30 years of playing. As far as efficiency goes, I'll just say that while a '68 Z28 Camaro may not be as efficient as a 2012 Toyota Prius, it sure is a hell of a lot more fun to drive!
Can't say that I've ever had an output transformer ever go bad in any amp I've owned in over 30 years of playing. As far as efficiency goes, I'll just say that while a '68 Z28 Camaro may not be as efficient as a 2012 Toyota Prius, it sure is a hell of a lot more fun to drive!
I share that sentiment!
Can't say that I've ever had an output transformer ever go bad in any amp I've owned in over 30 years of playing. As far as efficiency goes, I'll just say that while a '68 Z28 Camaro may not be as efficient as a 2012 Toyota Prius, it sure is a hell of a lot more fun to drive!
What I did not explicit told. The old heavy transformers that were used in industry earned a lot of money when these were scraped.
Most of them are replaced in the meanwhile by ....
Output transformers are a very different story.
I hope the transformers (line and output) of my svt will live some more years,
And if not, 10 miles away from home I know a company to fix any problems with transformers.
off topic of course but a interesting story.
I did a gig last night using my svt with my 212 cab.
The room acoustic seemed to be unproblematic.
But I needed to crank the svt a very lot to achieve the desired loudness.
Unfortunately the legendary svt grunge cranked the room acoustic and dashed the bass sound. It all sounded muddy anyway.
All my knowledge about sound adjustments and howto placing the cab in the room (the stage) were meaningless.
I wished this moment to have a class D amp with 1500 watt for clean headroom.
I did a gig last night using my svt with my 212 cab.
The room acoustic seemed to be unproblematic.
But I needed to crank the svt a very lot to achieve the desired loudness.
Unfortunately the legendary svt grunge cranked the room acoustic and dashed the bass sound. It all sounded muddy anyway.
All my knowledge about sound adjustments and howto placing the cab in the room (the stage) were meaningless.
I wished this moment to have a class D amp with 1500 watt for clean headroom.
And how would that have solved your problem? IMO, this has more way more to do with room acoustics and cabinet design, than it does the topology of your amps power section.
- Feb 12, 2006
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- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
All of this bagging on various this and that type of power supplies and power amps without the qualification that there are some very reliable SMPS/class D amps on the market and some very unreliable class AB amps on the market.
I think that before dog-piling on a particular topology, you might consider that the pro audio world at the highest level has shifted almost exclusively to SMPS/class D (with some exceptions) and the reliability is BETTER than with many of the older amps. This is the world that I come from, and I have designed products using both types of amps over the years. I don't dislike class AB, I don't dislike line frequency power transformers (there you go Bob) but I also understand that it's beneficial to many players to shed the size and weight (especially international touring players who fly with their amps).
I think that before dog-piling on a particular topology, you might consider that the pro audio world at the highest level has shifted almost exclusively to SMPS/class D (with some exceptions) and the reliability is BETTER than with many of the older amps. This is the world that I come from, and I have designed products using both types of amps over the years. I don't dislike class AB, I don't dislike line frequency power transformers (there you go Bob
) but I also understand that it's beneficial to many players to shed the size and weight (especially international touring players who fly with their amps).
