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[robertisonline]

I am running MC20 through [missing text] two active Yamaha HS7 studio monitors, and am having trouble understanding the framework or "big picture" of DAC's and preamps.

I have money burning a hole in my pocket, but need some education first. I have done some reading online but seem to find more opinions than answers. That this post is not related to JRiver specifically, my apologies in advance.

Best,

Robert

[JimH]

I'm not the right person to help, but your post had something missing.  I changed it slightly.

A DAC just changes a digital signal to analog.  A pre-amp or amp comes after that.

In general, spend a little before you spend a lot.  There are quite a few excellent inexpensive DAC's, no matter what people may say.

[mwillems]

The main purpose of most hardware marketed as a general purpose "pre-amp" in home audio is to route analog audio from different sources to your speaker.  In that sense calling it a pre-amp is kind of misleading as most of those kinds of boxes don't really add amplification.  They're basically a glorified mixing-board/switch.  Vinyl or RIAA pre-amps are different and apply both amplification and signal shaping to record player output, but many modern record players have those kinds of pre-amps built in.

If all of your audio is computer audio, there's literally no reason to buy a pre-amp. If you have analog sources outside of a computer (a cd or tape player, a blu ray player, a record player without a USB output, etc.) you might find a pre-amp useful.  

As for DACs, many modern pre-amps contain DACs, as do many modern receivers.  Most computers have built in DACs on the motherboard, and some modern active speakers even come with DACs built in.  Any time you have a digital signal turning into an analog one, there's a DAC in the chain.  But I assume you're asking about dedicated external DACs (or sound cards).

As Jim noted, nice stand-alone DACs can be had for relatively cheaply.  You can get stereo DACs with really very impressive measurements for $100 or so, and if you don't mind internal sound cards, you can do pretty well for even less.  Nice Multichannel DACs are more expensive, but even they can be had for a few hundred.  Be wary of DACs that cost many hundreds or thousands of dollars and don't have published measurements (or have measurements that aren't better than the cheap ones).  My advice is to focus on a DAC that does what you need (supports channel counts and sample rates you care about), and that has good electrical specs (lower distortion is better, higher dynamic range is better).

My personal favorite stereo DAC (with a sane price tag) is this one which retails for $150: https://www.jdslabs.com/products/46/standalone-odac/

You'd be hard pressed to find one with better specs anywhere near that price.  

For cheaper, I've also enjoyed this one quite a bit: http://www.amazon.com/Fiio-E07K-Portable-Headphone-Amplifier/dp/B00A9LHLQ6/ref=pd_sim_23_4/178-3590821-5245100?ie=UTF8&refRID=0DFJCNEYEDCWF5TMY738

It doesn't measure as well as the ODAC, but it's half the price has a headphone amplifier built in, and is portable, which are nice features if you want something a little more versatile.  

If you're in the market for multichannel output, I can make some recommendations as well.

[dfortney]

A DAC converts digital to analog.  It usually just puts out a fixed unattenuated line level signal (~2v rca, ~4v balanced, 3.5mm etc.).  The pre-amp just puts a dimmer on this signal essentially acting as the volume control, it could be even a passive component (no amp/power needed, a volume knob and resistor) but quality pre-amps are indeed active meaning they re-amplify the signal at the attenuated level 'decoupling' it from the output impedance of the DAC and giving the power amplifier a more robust signal to amplify.  Nowadays most DACs have the pre-amp built in, either digitally or as a discrete second stage of amplifiers with volume control.  So if your DAC has a volume control then this would be considered a DAC + pre-amp and you don't really need another pre-amp following it.

In general for best sound quality and lowest signal to noise ratio (snr) you want to preserve the full line level output of the DAC as long as possible before knocking it down and feeding it back into a power amp that boosts it back up.  In other words you want to preserve that full-scale full-resolution signal until you absolutely have to change it to satisfy your speakers/headphones.  It would be a mistake for example to use a pre-amp to reduce the DAC output to a very small signal and then get a bigger amplifier to bring that weak signal back to life because amplifiers add noise and distortion to the signal, some better then others. Instead you would want to leave your pre-amp volume control on its near max setting and feed it into an amplifier with less gain (power) which typically introduces less noise and distortion.

[mwillems]

In general for best sound quality and lowest signal to noise ratio (snr) you want to preserve the full line level output of the DAC as long as possible before knocking it down and feeding it back into a power amp that boosts it back up.  In other words you want to preserve that full-scale signal as long as possible.  It would be a mistake for example to use a pre-amp to reduce the DAC output to a very small signal and then get a bigger amplifier to bring that weak signal back to life, instead you would leave your pre-amp volume control on its near max setting and feed it into an amplifier with less gain (power).

Or you can skip the analog volume control altogether.  I have a DAC set to full volume hooked directly into block power amps that are gain matched to my speakers, and use JRiver's 64-bit software volume control.  I have at various times used fixed line-level attenuators between the DAC and the amps for safety, but if you select your amp power outputs to match your speaker tolerances carefully you don't even necessarily need those.  My current amps could not damage my speakers even if driven into clipping.  I wouldn't necessarily want to be in the room for that, but that's a separate issue.

A few years back, I migrated from a previous hardware based solution including a pre-amp and a "crossover in a box," and reducing the number of hardware components in my signal path has reduced my measured system distortion significantly. Admittedly my pre-amp was not the nicest, but any additional hardware in the path will contribute some amount of distortion (especially active components).  In the case of a well-designed passive pre-amp, the amount of distortion should be trivial, but a poorly designed passive volume control can be quite noisy (especially at certain knob positions).

JRiver's software volume has been rock-solid for me and I recommend it highly; in nearly two years of use I've never had a serious "blow through."  I had one or two near-misses, but those were purely user error (since fixed by more careful configuration).  

[pschelbert]

With that speaker you need a DAC with best symmetric output xlr or tr. Asymmetri dac may work as well but may be the output level is too low and you need an adapter csble. Prof DAC like RME work they have xlr and or tr out.