Yes - it really doesn’t address about matching stages between the pre amp and power amp. It talks a lot about digital volume control - which is quite common now in high definition DACs… however that is about the Controller - not the pre-amp per se.
So it’s a good sales marketing description above - I think however if it was instead technical it would become clearer and cause less confusion for those who don’t have an electronic engineering background.
Not all preamps have to have controllers or variable gain controls.
Kind of in my opinion - from an electronic engineering perspective an audio power amplifier is generally considered to include the following simplified building blocks… going back to some of my foundation under graduate memories…
In hifi amplifiers - the tonality control is usually dispensed with.
How the pre amplifier and power amplifier are implemented is up to product designs, such as integrated, separate, part of a specific source component etc - but the pre-amplifier has an essential role in the performance of an overall audio power amplifier - not least its frequency band matches the power amplifier frequency band to minimise distortion, impedance matching as well as the gains levels being matched.
So yes a pre-amp can’t create detail - but without it detail could be lost and distortion added for certain parts of the signal.
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If i could get away with just digital then i would certainly have just an amp.
Maybe in the future as more phono stages go digital like linn, and it doesn’t all sound the same then maybe, but i certainly don’t want my turntable to sound like my digital but w8th pop’s and crackles, i like how it’s different to my digital.
As said this is before the Apex board upgrade, and things certainly moved on and got much better with it.
As said what ever they do certainly works, and i guess most other manufacturers haven’t been able to pull it off as yet.
But certainly any thing you put in the way will 100% do something to that single, and 100% it will not inpove it. It may help your amp work, and so sound better. But if you can do away with a separate pre amp and get better sound in doing so, then why wouldn’t you.
I wish i could, and even now i still try and work out how i could do it, and not effect the sound quality off my turntable.
But my vitus sia030 has certainly eased the worry about it all, but would still do it if i could.
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Dunc, this looks like a cut and paste from a manufacturers promotional material. Please paraphrase with your own opinion using limited quotes where absolutely necessary. Thanks.
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It was a reply on a different forum, but i did just copy it.
It’s not from any promotional material, it was just an answer given.
But fine if you feel it needs to be removed, plus i won’t be responding as no real point.
That in itself is problematic with regard to forum rules and importing discussion from other forums…
So i guess the diagram above that simon has also copied is also against the rules then ?
Is it taken from a post on another forum?
Well, it’s obviously come from somewhere other than what simon has done, just like mine.
But as i have said, i am not bothered.
But lot’s off stuff on here gets copied and posted up, it’s just a shame that some gets deleted for some reason and other’s don’t.
I guess that’s life, as they say.
Anyway cheers.
The diagrammatic snip is from a thesis published in the public domain by the University of Gävle, Faculty of Engineering and Sustainable Development as it matches my foundation undergraduate scrawlings but looks neater 
Its a fairly stock simplified representation of an audio amplifier block diagram - kind of 101 electronic engineering.
I think you’ll find copying from other web forums/social media or even referring to some of their specific threads as well as copying commercial web links or marketing collateral text from other companies is against the AUP here.
This discussion takes me back to the last setup I ran before I got bitten by Naim. The front end consisted of three Meridian 500 series boxes with Musical Fidelity monoblock power amps in a rather unusual configuration.
The source was CDs played through a separate transport and DAC. But unconventionally I also had what Meridian called a Digital Audio Processor (518) and this was connected between the transport and DAC with the latter connected directly to the power amps. I guess you could call the 518 a preamp. It certainly controlled the volume, but it was entirely digital and not wired directly to the power amps. It was certainly no conventional analogue preamp and this was nearly 30 years ago. Plus ça change!
Roger
I’m afraid I don’t know either - and it would be quite useful to get a look at other people’s thinking on what to do when presented with an array of sampling frequencies. I have no idea what one is supposed to do with what comes out of a 384kHz sample rate. Obviously there’s zero information (that’s kind of a descendant of acoustic probability) and there’s the likelihood of quite a lot that’s spurious. Then again it’s crazy to go filtering below that frequency, when most of the point was to make the filter design easier and they think it’s carrying something useful. Personally, I think I’d want to slice it off - and probably not just rely on one of your main filters either.
Incidentally, I can tell you what the inherent bandwidth of most of these discrete preamps is, because I’ve been looking at a number of them lately from people like Neve, Naim, Graham Slee and Quad, and also seeing what I can do myself. Ignoring input and maybe output filtering, the gain sections have a bandwidth of about 4 to 10 MHz, and possibly higher since we don’t need so much gain these days. I don’t actually know where the modern Naim one falls as I don’t know what direction they’ve taken, except that nowadays you can set the level on all inputs, so they could have done anything they pleased.
Remember AM frequencies cover upto microwave…and beyond… modulation type has no bearing on carrier frequency.
Anyway the bandwidth of the complete amplifier will be typically designed to approximate the pass band…
Clearly there is no issue in designing analogue electronics upto microwave and beyond… but your circuit componentry and layout will appear quite different in physical appearance to the electronic circuitry and appearance of audio amplifiers… yes I am involved with RF engineering personally.
The output section similar to one of my RF power amplifiers (1.5 to 60 MHz)
But back to your point good audio circuitry will include safe guards to ground very high frequencies, such as parasitic oscillations and also bleed of gain etc… however induced very high frequency currents can interact with active componentry designed for significantly lesser frequencies typically in a none linear way (which I believe is what you may be referring to) causing inter modulation artefacts as well as affecting circuit feedback (increase in amp feedback increases amp bandwidth) and this is what can detract from the audio performance of an audio frequency amp.
I personally favour high frequency terminations in audio interconnects… because of the nature of them I believe are prone to RF induction (as opposed to RF break through) … to me the differences can be rather worthwhile… kind of difference of hearing a recorded voice from your speakers compared to wondering who is calling you… obviously subject to the components being used.
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I’m perpetually in awe of RF engineers and have often thought that AF designers should ideally have it, and the raft of useful techniques they have up their sleeves, as their background. Funnily enough, as I was writing that bit on the b/w of the gain sections I wondered, not for the first time, why Naim don’t put 100pf caps to ground at the inputs. I suppose that having optimised their cables (something they have an exemplary record in) you probably don’t want to add another metre’s worth of capacitance to them. They can reasonably counter that they do a fair bit of filtering of inputs but there’s a lot to be said for keeping it out of the box. My personal favourite example is what comes in through the speaker cables. Ever since Bob Cordell first wrote about it, and showed a mountainous looking graph of what he measured at the speaker end, I’ve done what I can about it and have always borne it in mind. This signal (noise) is essentially just one resistor away from the input LTP, and I often imagine the multiplicity of choices it has when it looks from the position between the output transistors and decides which way it would like to go. Interestingly, there may not actually be any path at all to a physical Earth, though I expect some capacitance to the casework will likely do the trick. These are the sort of things I had in mind, covered, quite impactfully I thought, when Martin Colloms said to me “They run around the amplifier like water.”. It’s like a new playground for them.
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Indeed… so many don’t get this… the optimum path to earth depends on wavelength… for my RF work I’m almost embarrassed to describe my ground sink… with electrodes at different quarter or 3/4 wavelengths around a central electrode around a band pass of RF frequencies… 
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Wonderful! And a lovely example of why I’m not going to be an RF engineer anytime soon. 
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