Per MindsMirror's suggestion, the Magni would go after the STX and in turn, would directly drive the speakers and phones:
PC --> Essence STX RCA --> Magni 2U (Pre Out) --> Sub --> Speakers
|
Essence STX 6.4 mm --> Magni 2U (Phones) --> Headphones
I assume I would run to the sub first in this setup (depending on cable lengths available) but the A5 still only has that 3.5 mm for an input. The STX would only be used as a DAC and for DSP in this setup.
That won't work. At least not very well. You'll be relying on y-splitters or what-have-you; there's no crossover, and there's no good way to "loop" the sub and the speakers. Sure the Magni could work as a preamp, just like any other device, but why spend all that extra money when the STX already has a headphone amp and you can have the same-size SYS for less money? Of course if you just want the Magni then so be it - it will also be perfectly functional, but it won't replace the need for a crossover to properly connect the sub.
How can you have a digital input without requiring a DAC? It has to be converted to analog at some point in the chain.
Exactly right - sorry if that was statement was unclear. My point was that a lot of newer devices only accept digital (e.g. USB, S/PDIF, etc) just because that's the trend, and price-wise it may be no different than an analog solution. Basically don't limit your options until you have to.
Ah OK, now I understand. So I don't have 2.1. That makes sense, since I can hear mids coming out of the sub. I always wondered why that was. So I would need another connection from the source (the STX) to the sub for it to be 2.1, right? I couldn't run the signal to the sub first and then the TRS on the speakers and have 2.1? The STX only has one stereo RCA out, plus the phones 6.4 mm. The only other output is the SPDIF. What is meant by "20-20?" The sub says it has crossover. It's marked "crossover" on the back of the sub. I think even the manual describes it as a crossover circuit. I have a switch that I can flick to bypass it. I'll try this out and see if there's a difference, but you said this isn't a crossover, so I anticipate it won't.
They can call it a crossover all they want, but its taking in a single full-range signal and driving its amplifier thru a lowpass filter. That isn't a crossover. And that's exactly why you hear mids through the sub - that's "wrong" because that driver/box isn't going to be voiced up that high, so its going to sound like mud and you've got it putting out a lot of distortion (even if its being masked by the speakers). This is why you need a crossover.
A separate connection from the STX would not, in and of itself, fix this - it would be another full-range 20-20 signal. I'm not aware of any soundcard that actually can do 2.1 bass management; many can do 5.1 but for whatever reason nobody takes that working crossover configuration and turns it into a working 4.1/2.1/n.1 configuration (by contrast, basically any AV receiver/surround sound processor/etc can do n.1).
Definitions:
"20-20" refers to 20Hz to 20kHz - the general range of human hearing. A lot of people can't actually hear all the way up to 20kHz (and even those who can, it's heavily attenuated; see "equal loudness contour") - there's not a lot of musical/etc content up that high either. Used here to specify "full range audio" - you're taking a 20-20k signal out of the DAC (or STX, or CD player, or whatever) and then you need to split it into the appropriate pass-bands for the various speakers (that's where a crossover comes in) so that the appropriate speaker plays its appropriate reproduction range (because the speakers aren't actually able to reproduce 20-20k - they'll reproduce some subset thereof).
This is what I considered before. Then I decided to consult you guys, the experts, cause I'm an audio newb. MindsMirror advises against this.
Well I don't understand his/her objection but hopefully in the below post its explained.
And indeed it does. Using the SYS (or any other passive preamp) is absolutely fine into an amplifier (which is what I'm suggesting) and MindsMirror isn't diasgreeing with that. What MindsMirror *is* diasgreeing with is hooking SYS up between a headphone amplifier's output and a pair of headphones, which I'd agree with, because SYS isn't designed for that. I don't want to start a big fight but "damping factor" is just marketing run amok, and while it was largely put to bed in the 1970s for speaker systems, it's come back around again with headphones because like the saying goes, everything old is new again. I completely agree with using a software/digital volume control where possible, because its usually more accurate (there are quality pots that can get good channel tracking and such, but they cost $$), but if you want that tactile control there's nothing wrong with an in-line volume control - there's no loss of "control" on the amplifier's side, and there's measurement data floating around the web showing OEM solutions that work this way (e.g. Creative ZxR) have almost no appreciable difference with or without the in-line pot.
Overall I don't think I'm in disagreement with MindsMirror on anything here.
[rule]Yeah, audio gear is designed with rackmounts in mind, so almost everything is designed with that form factor. If there was something the size of an alarm clock, great, I can handle that on my desk. VCR size is out of the question. If I'm going to have something that big, I want it to have a proper place. I cannot provide that at this time. I could theoretically put something rack sized underneath my monitor, but then that becomes an ergonomic problem, as my chair is at its maximum height. It's also a problem if the thing expels a lot of heat.
The AC500 and similar devices don't expel much heat (most DACs don't draw that much power), but I certainly get the ergnomoic argument.
Is this the AC500?
http://www.crutchfield.com/S-aRQXA2J75Pb/p_133SFDX7/Technics-SA-AX7-SH-AC500-Receiver-decoder-combination-package.html
Definitely too big. I had no idea there were so many options. It's a bit overwhelming. If I start introducing a lot of components, power becomes a concern, as well as available outlets. I think I have three or four available, but I'm not sure of the power draw.
It's the box on top. The box on the bottom (SA-AX7) is a multi-channel amplifier. Power usage is very minimal (measured on mine at around 10W) which is pretty typical of many DACs - they just don't need gobs of power to do what they do (And as a result don't get that hot). Look on ebay - its been discontinued for some years. Last I knew they're around $100.
The SYS/Rolls setup would easily fit the "alarm clock size" form factor as long as you can accommodate the wallpack for the Rolls, but that's easily enough addressed.
Well no, it obviously wouldn't be the encoding, because whatever your files were encoded at is fixed. What isn't, is the downconversion after Windows converts everything to 24/192 KHz from 32-bit floating point. By dynamic range, you mean how far I can turn the volume down from 100% before I lose resolution, right?
Firstly we can't talk about "Windows" in a monolithic sense - there's significant differences between how Windows 9x, NT 5.x, NT 6.x/10 handle audio internally. The NT 6.x/Win10 family (I'll assume that's what you're using since its most common by market share) offers multiple paths for SRC, two of which are very high quality, and one of which uses a more linear filter that can introduce some spurious noise (which is arguably audible) - when and where applications call these different SRC snap-ins is not consistent, but generally applications (including Windows Media Player) are (or should be) calling the higher quality SRC that is more or less transparent. If you're taking a 16/44.1 file and playing it, if the output is set to anything but 16/44.1, SRC is happening (and that may be via Windows, your audio driver, your audio hardware - its happening somewhere) - and it's at that stage (where SRC is happening) that you may get into audible differences due to the filters used (e.g. Windows' "low quality" filter adds distortion, some older Creative cards have problems with SRC and fidelity, etc). My suspicion is that it's more likely you're hearing a difference between SRC filters than "converting 16/44.1 to 24/192 makes it sound better" because the later simply isn't true; if it's done right it sounds the same either way because the SRC should bury its noise below the noise-floor of the equipment/data. HOWEVER, you may be getting more dynamic range out of the DAC if they operate better in 24-bit, thus it would be an overall benefit to do this with clean SRC (which isn't impossible to achieve), and there are plenty of stand-alone DACs that do this internally for that very reason.
More on dynamic range:
https://en.wikipedia.org/wiki/Dynamic_range
No, it isn't "how far you can turn the volume down before you lose resolution" - at least not entirely. Some digital volume controls do drop bits which results in a theoretical loss of resolution, but what's usually absent from those discussions is that the output signal gets quieter, so you're probably losing fidelity (cf equal loudness) and competing with the environmental noise floor before you'll notice the drop from (for example) 24 to 20 bits of resolution. The bigger problem with digital volume controls is if you're artificially "boosting" the signal because you can end up clipping (which sounds nasty) and unfortunately some digital controls, 100% or 0 dB is actually higher-than-100% internally, so you end up with the potential for clipping if the incoming signal is hot enough (which is unfortunately the case with many newer recordings).
Thank you again for your suggestions. It is inconceivable to me that there are so many approaches to this problem.
No problem. And yes, there really are a ton of approaches here, and there's plenty that I'm probably not "seeing" or thinking of - don't consider my alternatives as an exhaustive listing of ways to skin this cat, but more food for thought to get you going in the right direction.
I'm not sure if you really need a crossover. The sub has a variable low pass filter circuit in it, that's what the crossover frequency knob is for. And your speakers response is naturally high pass filtered probably around ~60 Hz, so in theory you could set your sub's crossover to pick up where your speakers leave off without needing a receiver or separate crossover to do it. I guess it depends how you want to use your sub. I don't have experience setting up a sub and it sounds like obobskivich knows more about that than I.
In theory that can sort-of work, but in practice it's less than ideal. The reasoning is:
Neither of those F3 or -10 points are brick walls, but instead represent some sort of roll-off. There's also nothing acting as a high-pass to the speaker amplifiers, so there's inefficiency there when it comes to the amplifier (e.g the amplifier still sees the 20-20k signal and is actually trying to drive that out - just because the cabinet has no usable response at 20Hz doesn't mean you aren't paying for it anyways). So without a complete crossover it's more or less impossible to nail that "zero crossing" where the sub and speakers blend together nicely - the goal isn't just overlap, but overlap where they're both down a certain (and equivalent) amount to allow seamless transition. E.g. if you dialed both in at probably around 80Hz (and I'm gonna bet that 60Hz is probably a -10 for a bookshelf speaker) and the crossover performs roll-off on both sides, ideally both are down say -3 at 80Hz and thus the averaged response is "flat."
It also prevents the whole "mids on the sub" thing.
The other advantage to having a crossover is that you're sending a full-range audio signal into it, and its splitting things up for the outputs. Not only do you get a single point volume control ahead of that (so you only have to worry about one volume dial to turn), but you're also not having the amplifiers on either side taking the full-range signal, thus improving efficiency (you'll pull a lot of distortion off both sides).
Overall the crossover is just a better way to do this.
Maybe you do want to have the sub handle a broader range than just <60Hz, without blending with the sound from the speakers. In that case you would need a crossover. I see no reason why a simple passive stereo crossover could not exist, which takes the line signal from a DAC or preamp, low and high passes it, and sends those signals to a sub and speaker input respectively. The only think resembling that I could find in a quick search is
these inline RCA crossovers. You would need a Y-splitter, one pair of low pass to go to the sub, and one pair of high pass to the speakers, and they're fixed frequency, not variable. Again, I don't know of everything that's available, perhaps a better solution exists.
Fixed solutions are fine except without honest numbers (which most manufacturers won't give) and some sort of way to verify room response, you're kind of shooting in the dark (still way better than nothing). I linked to a stand-alone, simple, variable active crossover that will accomplish this and also provide trims and such that would work too, and give you more flexibility in getting what you want. The Technics DAC I suggested (along with most any AVR) will provide such a crossover digitally - at the most basic they'll generally hover somewhere around the THX design guidelines at 80Hz, and with newer and more sophisticated models they'll provide a lot more programmability (e.g. variable crossover, EQ, etc) owing to their greater DSP power (there's also stand-alone solutions that can do this, like the Velodyne, or with snap-ins for miniDSP).
I wouldn't like the idea of having to use a receiver just for a stereo system. All the receivers I've used consume a ton of power and put out lots of heat. I tried using a receiver once with my computer system, I had it under my desk in a small bedroom and it made it so hot under there that it was impractical for use in the summer. It was great in the winter though, I could keep the doors closed and my room would stay stay warm enough that I never needed to turn on a heater.
AV receivers vary - some absolutely do run very hot and waste a ton of power when idle. Some don't. Usually a lot of the newer whiz-bang models with a ton of digital video processing tend to use a lot of power just to idle (like 100W), because there's so much computer goodies going on there. But somewhat older models can knock that down considerably (e.g. it isn't surprising to see idle at more like 50-60W). In both cases it won't come much up from idle because the amplifiers won't be seeing any loads. Stand-alone AV processors (like the Technics) cut the entire amplification section out, so the power draw is almost nil.
