Is my DAC my weakest link?

Hi everyone,

I'm new to this sort of thing. I recently bought the following system used:

Thiel CS2
Rotel RC-1070
Audionics BK-ST 140 (BT-2)
NAD 5000
Music Player II DAC

It sounds great and I am very happy with it. I am wondering, though, whether the Music Player II might be outdated. I know everything is old (hopefully some of it in a classic sense), but I have been wondering whether more recent technology might have greatly improved DACs. Would it be worth it to invest in a more recent DAC, and if so, what price point would be roughly commensurate with the system? (i.e. no need to improve the DAC beyond the capability of everything else).

I stream Tidal HiFi through Audirvarna Plus to the DAC.

Thank you for your insights!
mate, i looked but cannot ID your DAC... can you post a link to the product?
The issue with DACs is that modern one's (< 10 years old) do much better with Redbook (44 kHz / 16 bit) playback than old DACs.

If you can hear a big jump in sound quality when you go to high resolution, that goes away with most DACs today.

I like Mytek, Schiit is also an inexpensive option which works really well. Topping is an absolute bargain if they fit your budget better.
I recommend the Chord Mojo. There is one currently listed for less than $400 on Agon. It's not mine. I use the Mojo as a headphone DAC when traveling. I know that others on this site use the Mojo as the primary DAC in their home systems.   
FYI, the link the OP provided is to a review of his DAC:

HRT Music Streamer II

High Resolution Technologies Music Streamer II USB DAC

Based on that component list I would have to say your weakest link is the lack of power cords, interconnects, and speaker cable. Power line conditioner? My guess is you are still using the factory fuses. Cables laying right on the floor. As Kurtz says in Apocalypse Now, "The horror. The horror."
Thanks to everyone for your input! I will definitely check those out.

millercarbon, I don't know what interconnects and power line conditioners are. I do have some cables in midair and some on the floor, you're right--I should avoid that, I take it? I will ask whether they are the factory fuses. Some cables are monster and some are audioquest, but I don't know what kind exactly. The speaker cables are probably original I am guessing.

If you are looking for a good, inexpensive power conditioner, I recommend Furman with SMP and LiFT. The least expensive unit is still pretty good and a relative bargain compared to pricier brands:.

The biggest drawback of this unit is the lack of multiple filter banks. For that you need to move up the ladder in Furman units, or Shunyata or what have you, but given how expensive they get, it's cheaper to buy several Furmans. :D
@ryunosuke13 - What amp do you have? You say "Audionics BK-ST 140 (BT-2)". However, that doesn't seem to be correct. 

Audionics made a pre-amp model BT-2 and B&K made an amp model ST-140. I'm guessing your amp is a B&K ST-140, correct?
I second the suggestion to try Chord Mojo. Compared to old dacs it may already be staggeringly good. I have a Bricasti M1 SE but Chord is very very good indeed at a fraction of the price. 

Some manufacturers of high quality dacs such as Benchmark also allow in-home trial with free returns (minus shipping costs, which are moderate).
+1 @erik_squires on the Furman recommendation for your system. A power conditioner basically does what it sounds like it does. It makes sure the power your system sees is, in easy terms, "clean and steady." The electricity coming into your house has audible noise in it and it doesn't always (or ever) come through the lines in a uniform, steady flow--electricity surges--and a power conditioner helps harness this attribute and provide your equipment with a steady diet of cleaner and steadier power. I've oversimplified but hopefully the explanation helps you. BTW there are many folks on this site who don't use any power conditioning because they do not think it adds significant value. I have run previous systems without power conditioning. However, I am now a strong proponent of using power conditioning. FWIW the Chord Mojo will probably provide you a more discernible audible improvement in your sound than an entry level Furman. But that doesn't mean the Furman isn't a good idea for you. 
There is nothing wrong with the AC power coming out of your outlets! Don't fall for all this "power conditioner" B.S. Same for interconnects! Use what you have and enjoy the music! There is NO benefit to raising speaker wire off the floor! Enjoy your system and don't become a neurotic and gullible audiophile!
Concentrate on source and output (speakers). You got fine speakers. A bluesound node2i will give you good streaming and dac with subbass output if (when) you need more in the lows. Make it simple. Try to find out what sound you like. Move the speakers around in the room. Don't take your time and wallet comparing cables. Have fun!
I have a Marantz SA-10A CD player and DAC. It is as good as any source I have including Vinyl. CDs are superior to almost streaming service when played on top rate equipment. 
Since you are streaming Tidal Hi-FI through Audirvana I would recommend a DAC that can handle MQA. The Mytek Brooklyn is probably the best overall (for the price) but if you just want to get your feet wet you could try an Audioquest Dragonfly Red or Meridian Explorer2 DAC and either return them or keep one for travel or a smaller system (I have the Explorer2 hooked to a MacBook Air and powered speakers in a secondary office). 

If you like the sound but want to move up you could try the Project Pre Box S2 Digital or the new NAD C658. 
OK, so you bought an existing, older system. Most all of the components were of good quality, mid-priced at their time (except the DAC that was a budget item). Some of the components, such as the power amp, may be old enough that they need service (especially replacement of the capacitors). The real winner in your components is the speakers. If they are in good working order, the are worthy of upgrades to the electronics.

I agree with @towertone - A Pro-Ject Pre-Box S2 pre-amp/DAC could replace both your Rotel pre-amp and your HRT DAC. It has gotten really good reviews, it unfolds MQA from Tidal and it is really inexpensive at $399 MSRP. You can use it for your Tidal streaming setup and as a DAC to improve the SQ from your CD player. Buy it from a local dealer (if you have one) or a vendor that offers returns, such as Audio Advisor. Try it and keep it if you believe it provides an improvement in sound quality. If not, return it during the return period.

Past that, you amp (I'm assuming it is a B&K ST-140) might need service (capacitor replacement). You could also replace the amp with something like the  NuForce STA 200. There is a Demo unit on sale at Audio Advisor right now for $430.

Enjoy the journey. Enjoy the music. Don't get too caught up in the equipment, unless you have deep pockets. If you are enjoying what you have, don't buy anything unless you have the available funds. Spend time and effort on speaker placement and room acoustics. It's free (unless you buy room tuning devices) and can provide good improvements in sound quality.
This is really wonderful advice. Thank you. It's a lot easier to think about laying out money for a DAC, if it gets me an upgrade on the pre-amp too! 
BTW Chord Mojo will also drive the power amp. It is also a great portable solution for travel ---which is my main use.
Chord Mojo looks awesome but looks like it doesn't support MQA.

Would the Pro-Ject Pre-Box S2 take input from a CD player? Looks like it has optical and USB in, plus a single coaxial input.
If CD player has optical or coax SPDIF output then you would be good to go using the Pre-box as DAC and preamp.
The DAC is the most important part as it will convert the lossy digital data to analog. Jump to chord dac and you will see
 Eddie,   Buy a real nice power cord for the DAC  be done with it.   also same for the server  
Up to a point I agree with reubent but... big but. With digital stuff it is different. Digital is a whole different ball game. Since the human ear is extraordinarily sensitive to anything that sounds un-musical, it can react to seemingly very minor shortcomings which sort of bug you until you either just throw your whole digital rig in the trash and go back to analog, or upgrade.