Nah, he just regurgitates what everybody else says.
He's a member now? Does he play flats?
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Does this mean Class D amps are in fact digital ?
- Thread starter Thegreatzambini
- Start date
If I say, "yes" can I run for something?
With infinite wattage comes infinite responsibility.
- Feb 12, 2006
- 60,986
- 5
- 220,768
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Is there such thing as spiritually pure monks? Sounds a little like unobtanium...
What about Class G for "gagsters"?
A quick google brings up the manual for the Genz Benz Shuttlemax 9.2.So are you gonna tell us the manual you quoted?
A post from Mr. Agedhorse.
Is it just me or are newer lighter rigs just lacking 'balls'?
I hate to break the bad news to you, but class AB amps also switch on and off, the positive going waveform devices shut off and hand off to the negative going waveform devices which turn on and then switch off as they hand the signal off to the positive going devices as the waveform becomes positive again. This happens at all frequencies simultaneously, at twice each signal's audio frequency component.
For all the snake oil discussions about class AB being continuous and class D being a switching amp, most neglect to mention that class AB/G/H are also switching amps of sorts. Managing the crossover artifacts at the hand-off points can be a bit of a challenge since they vary with temperature too.
I've designed both class AB/G/H amps and class D amps, each have their benefits and drawbacks, both can be difficult to design if looking for good, reliable results.
Here's what the current waveform looks like on a class B amp:
Class AB overlaps the dead zones by slightly forward biasing each half of the output stage, it's close but not perfect. This shows each half conducting with a slight bit of overlap:
Class D doesn't suffer from signal crossover issues, it's all based on differentiation and integration which results in a continuous signal from top to bottom and bottom to top. The switching occurs at roughly 350kHz, much faster than a typical analog to digital converter:
Here's a class G/H amp which has the same signal crossover issues as above plus additional switching of the high and low rails in and out at audio frequencies. The venerable and often worshiped CA-9 has 4 rail switches plus the signal crossover switching. If you look on a scope, the switching artifacts are visible, but like with class D, it's not audible in well executed designs.
Just remember those friendly words of advice on the front cover…”Don’t Panic!”
More bad news.
I asked Bard, the storyteller, and it said:
Are recifiers switches?
Yes, rectifiers are switches. They are devices that convert alternating current (AC) to direct current (DC). Rectifiers use switches to allow current to flow in only one direction.
...
Yada yada yada
...
Therefore, old time Line frequency power supplies are actually:
"Very Low Frequency Switch Mode Power Supplies"
That's right, no matter what they're called, power supplies use switching to convert AC to DC.
Most every SMPS starts with a line frequency switching diodes.
Modern supplies are a mix of old century and new technology
Change is hard.
I asked Bard, the storyteller, and it said:
Are recifiers switches?
Yes, rectifiers are switches. They are devices that convert alternating current (AC) to direct current (DC). Rectifiers use switches to allow current to flow in only one direction.
...
Yada yada yada
...
Therefore, old time Line frequency power supplies are actually:
"Very Low Frequency Switch Mode Power Supplies"
That's right, no matter what they're called, power supplies use switching to convert AC to DC.
Most every SMPS starts with a line frequency switching diodes.
Modern supplies are a mix of old century and new technology
Change is hard.
Mine is digital in the sense that I use my fingers to turn it on and twist the knobs...
The output of a Class D amplifier is never truly off. It switches between the negative and positive rails, but the switching is done so rapidly that the output signal appears to be smooth and continuous to the human ear. It cannot be considered a digital. Digital signals are represented by a series of bits, which can be either 0 or 1. In contrast, the output of a Class D amplifier is a continuous signal, meaning that it can take on any value within a certain range contained in a period of time.
