Cool.
For the headphone amp I'm able to rather better than that, using modern, high gain silicon devices.
I'll let you know how the scaled up power amp version fares.
Transistorized power amplifiers suitable for driving loud speakers are known. A variety of configurations may be used for such amplifiers, such as complementary symmetry transistors (one PNP and one NPN transistor or one P-channel and one N-channel FET) connected as push-pull emitter followers or push-pull common emitter stages; or like conductivity type transistors (both PNP or NPN transistors or both P-channel or N-channel FETS) may be used in a push-pull configuration, with one of the transistors being operated as an emitter follower and the other of the transistors being operated as a common emitter stage.
While these systems provide a way to power a loud speaker system, several problems are associated with each of the prior art systems. For example, when a common emitter stage is used in a push-pull configuration in conjunction with an emitter follower stage, the gain characteristics of the two stages forming the push-pull circuit are inherently unequal. Consequently, feedback circuitry must be employed to compensate for such differences, and to reduce the distortion caused by such differences. Such feedback circuitry usually takes the form of an external feedback loop, such as collector to base feedback. Similarly, feedback must be employed when two complementary symmetry stages are connected in a common emitter configuration to reduce distortion inherent in common emitter stages. Such feedback increases the complexity of the amplifier, and reduces its stability.
Another problem associated with the prior art transistor amplifiers arises in the coupling of the loud speaker system to the output of the amplifier. Direct coupling to the amplifier is advantageous from a simplicity and low-frequency response standpoint, but such direct coupling results in a direct current path through the loud speaker which can cause excessive direct current to flow through the voice coil of the loud speaker. Such direct current can adversely bias or saturate the voice coil of the loud speaker and result in distortion. Consequently, in order to avoid such a direct current flow, the prior art amplifiers utilize coupling capacitors in series with the loud speaker to block such direct current flow, or employ a split power supply that maintains the potential difference between the terminals of the amplifier to which the loud speaker is connected at substantially the same potential.
The use of capacitor coupling has the disadvantage that unless a very large capacitor is used, an attenuation of low frequencies results. Furthermore, the use of a capacitor in series with the loud speaker can produce a loud pop in the speaker during the time the capacitor is being charged after the unit is turned on. The use of a split power supply requires precise balancing of the amplifier, and usually requires a balance control to maintain the output terminals of the amplifier at the same potential. Furthermore, failure of a component in the output or balancing circuits of the amplifier can cause substantial direct current to flow through the speaker. In addition both solutions significantly increase the cost of the amplifier.
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Oh I get it. Otherwise you couldn't see the forest for the tree?
Now THAT was funny.
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Reproduced music cannot reconstruct truly and fully live music. Agreed.
So?
Is there a design concept for audio amplifiers you offer, or is it hat, according to you, all amplifiers are futile?
Unfortunately, Soundminded, the detailed commentary that I put forth this morning, discussing our differences, has disappeared, and I am reduced to just a few words, that sometimes pass on to be be seen by everyone else. I would have thought you more refined when it came to the Arts, but I must have been wrong.
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This definitely doesn't answer my question.
Here we go again:
Reproduced music cannot reconstruct truly and fully live music. Agreed.
So?
Is there a design concept for audio amplifiers you offer, or is it hat, according to you, all amplifiers are futile?
How many audio amplifier designs exist? 10,000? 20,000? 50,000? 100,000? Why would one more matter when there are so many out there which perform just fine? I built my first audio amplifier when I was 10 years old. Not from a kit but from the schematic in the back of an RCA tube manual. I used old radio parts I found. I didn't even have the right amplifier tube. I needed a 50EH5 but used a 50C5 instead. I bought an aluminum chasis at Lafayette radio for about $3. I found a tool and die set and punched to tube holes, drilled out the screw holes for the tube sockets. I was amazed when I hooked it up to a crystal phono cartridge and a table radio speaker and it worked. I've seen, heard, built, owned countless units. My professor Paul Chirlian wrote the book. One more amplifier or preamplifier won't slove anything. The whole approach needs to be rethought.
As for "Reproduced music cannot reconstruct truly and fully live music" I consider that a temporary situation, a problem that will be eventually solved. But not yet, not by the people working on it now, at least the ones I'm aware of. They aren't up to it, it's beyond their capabilities. A discussion looking for the holy grail in one more preamplifier, one more amplifier, one more speaker system, one more wire or cartridge is proof. You can hit your head against those walls all you want, they won't fall over.
I was a swim team parent for a while, it's amazing how many 8-12 yr olds are embarrased to wear a Speedo in public.
Hi John, indeed, I can tell the audible differences between different amps, both pre-amps and power amps. You know, it is a two-edged sword, since it cost me more money than I dare to think about.
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So, are you saying that all existing amplifiers are equally inadequate?
Or are some of them less inadequate than others?
What should a music lover do (aside attending live concerts) until really good amplifiers will come up?
On second thought, Steves design would have been WONDERFUL for my 1960 auto radio that was in my Renault Dauphine. Their approach was much inferior. It would appear that this approach would have been too expensive, but it would have been better.
Please remember everyone. PNP transistors made of germanium were the ONLY practical devices, besides tubes, at the time. The choke would have been OK in that situation, AND the distortion would have been lower than my SINGLE germanium power output transistor had. Those 6V6's in pp pair, with output transformer, certainly was better, and that I had installed in my previous auto.
Please remember everyone. PNP transistors made of germanium were the ONLY practical devices, besides tubes, at the time. The choke would have been OK in that situation, AND the distortion would have been lower than my SINGLE germanium power output transistor had. Those 6V6's in pp pair, with output transformer, certainly was better, and that I had installed in my previous auto.
The point being made by Soundminded (as I understand it) is that the present total approach to reproduction of acoustic music will never be realistically accurate enough to hoodwink anyone with decent experience of live music.
One outcome of this is the point being argued: That no amount of refinement of the concept and design of a pre-amp (or any other single link in the replay chain) will in any way alter the above fact.
Taken to conclusion the argument would indicate that every single stage of the audio chain from live performance to that which enters the ears is irredeemably flawed because the underlying total concept is of itself irredeemably flawed.
One outcome of this is the point being argued: That no amount of refinement of the concept and design of a pre-amp (or any other single link in the replay chain) will in any way alter the above fact.
Taken to conclusion the argument would indicate that every single stage of the audio chain from live performance to that which enters the ears is irredeemably flawed because the underlying total concept is of itself irredeemably flawed.
That's pretty much how I understand it as well.
Don't see how one can realistically re-create the soundfield from a live event with two speakers in a typical listening room.
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In my way of looking at it there may well be a different as yet undiscovered method by which this requirement could be met. But that is not the business of this site or of this thread in particular. It may well however make for a very interesting thread in the everything else section....but if some of the regular participants of, say, the Pass Pub thread get in there then it is more likely to be amusing than substantive!
In the meantime we can only take the whole matter of sound reproduction as relying on what we have already available - especially regarding stored sound sources.
In the meantime we can only take the whole matter of sound reproduction as relying on what we have already available - especially regarding stored sound sources.
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