Gain / Amplification
Ok, dumb question maybe….maybe the more troll-like members could chill on this one. I was just wondering, is there likely a quality-of-sound difference between utilizing maximum gain (say, out of a CD player, to keep it a simple scenario) and needing much less amplification from your amp, or is it in any way different to set your CD gain/output volume at a lower level and let your amp do its job? Let’s say balanced connections, so that’s added gain as well.
Question just kind of occurred to me when I fired up my Oppo for first time in awhile and it was **LOUD**. Which is not an issue, I was just wondering, circuit design-wise and engineering-wise, should one or the other provide a better sound ?
JH
itsjustme thanks that’s exactly what I think I was looking for. Yes, it’s an Oppo 205 with great ESS chips, and I run it thru a Parasound Halo Pre to a Parasound A21+. Despite the ESS chipset, if analog volume control (at the preamp) is [circuit design/engineering wise] “better” than how it’s done in the digital domain, that’s what I was trying to confirm. Obviously everyone’s situation will be a little different depending on their specific gear and other variables.
Thanks all. |
Given what you just said, i took a look at the parasound. Apparently it uses a relatively new B-B (TI) chip based resistor pair volume control. I have a bunch of experience with such chips, but NOT the BB. They are very good, but my experience drove me to design my own discrete equivalent. Maybe the BB unit is better than the several i designed with. So.... if the ESS let’s you do volume control via digital math without the "truncation problem" - i would tend to use the ESS volume. On the other hand the BB chip in your Prasound is basically a bunch of chip resistor pairs with chip switches selecting one pair vs another which is also pretty darn good. So i don't think you have a clear cut winner either way. If you want to learn more about digital volume control and its norml issues and why ESS is different they have a good PDF slide presentation on it available publiucly. Warning: math. Further thought (edit/add): the downsides of these "digitally controlled analog volume array chips" (what a mouthful) are the basic material used, and the fact that 90% of them depend on the inclusion of a chip opamp gain/buffer stage. Its one reason i ruled out many of them. here’s the point that’s relevant to you: those distortions exist whether you employ the volume in the Parasound or not. Its not like by setting it to full volume, the opamp is eliminated. Its still there as a buffer. I am not criticizing the design BTW - there are convenience / cost / sound / tade-offs everywhere. |
Interesting.... @jhajeski , I’ve played about with pre v. gain for awhile, settled down to 50~80% pre for volume control, and leave the amps running @ 75~80. Unless running a ’stress test’ on a diy...then I unleash it. *L* Room is louder than the system, so I keep that in ear.... Yak se mas? |
