Author Topic: High Efficeintcy Drivers and Amps  (Read 2181 times)

Offline rollo

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High Efficeintcy Drivers and Amps
« on: February 07, 2018, 10:58:36 AM »
   Over the years it has been the rule of thumb to use SET with these type drivers. hen came along Nelson Pass with Current source amps the F7.
  According to Pass there are so many good reasons to use such a design over SET, PP ,etc. Enter class "D" a current source. Class "D" may be a contender.
  Does anyone here have experience with using current source in lieu of SET for HED ?


charles
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Offline Emil

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Re: High Efficeintcy Drivers and Amps
« Reply #1 on: February 07, 2018, 11:27:17 AM »
I gave the First Watt M2 a try with my horns and was disappointed considering the M2 was designed to mimic an SET amp.
The M2 just didnt have the "bloom" of a good SET. Sounded flat IMHO
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Offline steve

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Re: High Efficeintcy Drivers and Amps
« Reply #2 on: February 08, 2018, 08:10:40 PM »
   Over the years it has been the rule of thumb to use SET with these type drivers. hen came along Nelson Pass with Current source amps the F7.
  According to Pass there are so many good reasons to use such a design over SET, PP ,etc. Enter class "D" a current source. Class "D" may be a contender.
  Does anyone here have experience with using current source in lieu of SET for HED ?

charles

I often have a problem with generalizations, by whoever, concerning the quality of different amplifiers. The reason is because not all designs are the same, or even work the same, even though the design may look similar. The principles can be quite different. It is important to understand the unique designs that some bring, or don't bring. Nelson could not possibly see all the designs.

I see very few excellent designs. Nearly all designs that I have seen have inherent flaws that are easily recognizable upon seeing a simple schematic. No listening testing necessary.

So what is a designer/manufacturer suppose to do? The above comment from Nelson makes me look like a second class designer and a  little disgruntled because I know the statement is not true.

For instance, I used to design PP triode amplifiers that, upon lengthy, specialized listening tests using a great many source selections, was truly accurate to the input of the said amplifiers. Special listening tests, not measurements. The only considerations I have to worry about were how the amplifier output mated to the speakers, which included the speaker cables (I prefer to use the term wires), the accuracy of the speakers themselves, and the room etc. But the PP amplifier itself was truly accurate, and of course very naturally musical.

Part of the achievement was due to the perfection of the preamplifier, its stage. Once that was achieved, the knowledge gained was very advantageous to designing other stages, including the output stage, because I understood the correct design parameters. Just needed to work on my personal speakers.

The advantage of PP triode amplifier was not only the sonic accuracy that could be achieved, but the power output, as class AB1 is fine for many if not most applications. If 120db is necessary, your ears won't be good enough to tell the difference anyway. 

The problem I think Nelson is referring to is the lack of credible designers/engineers with descent designs. From the schematics I have seen, virtually none. Maybe some class D will be an improvement.

I suspect his comment is formulated by all the average designs he has also seen.

My .02 rant.

steve
« Last Edit: February 08, 2018, 08:12:23 PM by steve »
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Offline mikeeastman

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Re: High Efficeintcy Drivers and Amps
« Reply #3 on: February 11, 2018, 01:53:34 PM »
I have Serenity Acoustic Super 7s which are 97 db and I was driving them with a modded duel mono Ncore 400 and they sounded great. I just replace the Ncore with the new Icepower amp from Mivera audio and they sound even better and the amp is not fully burned in yet.
Mivera PureMusic,  Serenity Acoustics Super 7s w/ upgraded xover and Neotech gold/silver wire for tweet and mids. DIY Neotech gold/silver wire speaker cables. PI UberPuerto