Journey Into Mystery: Building a Sound System on my Back Deck

If you know me, then you probably know that I go through phases. I get obsessive and maniacal about stuff on a rotating basis. My most recent phase is high fidelity (HiFi) sound on a budget, and it's been perfect for me in the sense that it's intensely, endlessly complicated with no obvious end-point in sight.

Our back deck canopy

It turns out that like Triathlon, HiFi is a journey, not a destination.

This all started innocently enough. I wanted to improve the sound quality on our upstairs TV by hooking it into the bookshelf speakers that we have connected to our record player. As a stretch goal, I also wanted to add a subwoofer, if possible.

The upstairs speakers are Edifier powered speakers (R1700BT) that I got in lieu of a gold watch for 20 years of faithful service to my current employer. They're not bad. They're Bluetooth speakers, but they also have two sets of RCA inputs, so I was able to run lines from both the record player and the TV at the same time without a separate receiver.

I didn't really appreciate this until I got into this project, but the fact that they're powered speakers -- meaning they have their own internal amplifiers -- made the dual RCA inputs a lot more important. This initial project would've been way simpler if these were passive speakers, i.e. speakers that need an amp. I could've bought a one-piece amp-receiver with a subwoofer output, and that would have been that. 

The fact that this was impossible launched this little science project.

It turns out that upgrading the sound in a meaningful way from these already decent $200 speakers looked like quite an expensive proposition. Indeed, if we were gonna spend that money, the first thing we needed to do was to consider the way we'd set up our room. Because speakers have directionality and what we might think of as a natural Engagement Area and Beaten Zone. 

This figure shows the impact area -- the beaten zone -- of an M2 machine gun.

We're talking about literal sound waves here, so yeah. Obviously. Having furniture in the way also matters quite a bit, as does the speakers' isolation from the dampening effects of being on a floor or book shelf. You can test all of this at home to appreciate the kinds of impacts room design can have. I did, and it was noticeable to the point that I could not unhear it afterwards.

With that in mind, this whole HiFi thing reminds me a lot of buying wine. A donkey can spend $200 on a bottle of wine, but if they don't know anything about what they're drinking, can they appreciate it? Will they even know if their wine was worth that money? 

A lot of times, when you buy expensive wine, what you're really buying is the shelf-space to age it so that it mellows. This can impact the price astronomically, but past a certain point, the flavor variations become quite subtle. If you're into wine, then maybe experiencing those subtle variations makes sense. For most of us, though, we're better served buying something similar but less extravagant. If a $17 bottle tastes 90% as good as a $200 bottle, then you have to be a serious enthusiast to appreciate the $183 opportunity cost of that last 10% taste differential.

For me, I've long since passed ten thousand hours as a competitive swimmer. I can feel and appreciate very subtle differences in the way I swim from day-to-day. With all that time in the water, a 2% change in performance feels like a legit step-change in my personal experience. So $183 for a 10% change makes total sense for me... when I'm in the pool. 

Alas, I don't think there are all that many other spaces in which those kinds of subtle variations make nearly as much difference to my personal experience.

What makes expensive speakers so expensive, anyway?

Von Schweikert Audio Unifield 2 Mk III Loudspeakers ($11K)

It's like anything else. You're paying for the engineering. 

Super-genius sound engineers spend inordinate amounts of time trying to figure out how to shape the speaker bodies to best mold sound across a wide range of dynamic frequencies. However, basic speaker tech has been around forever, so we're talking about incremental improvements, especially past a certain point. The speakers themselves -- woofers, tweeters, etc. -- matter some, but mostly what matters is the housing body material -- its density, composition, and shape -- and, as noted, the way you have your room set up. You also want to make sure that you isolate your speakers sonically from the dampening impacts of being on the floor. Hence speaker stands, which can get quite expensive in their own right.

I got this far into my project and realized that the easiest thing I could do was to improve my existing speakers' sonic isolation. As noted in a previous post, this turned out to be both cheap and easy using some small silicon feet I got from Amazon.

For $9.95, I got enough feet to isolate my bookshelf speakers and both our sound bars.

This, along with a slight rearrangment of the furniture in our living room, made enough of a difference that I soon realized that we didn't actually need a separate subwoofer. We might still upgrade this space at some point, but if we do, it will be with a set of passive speakers connected to an amp with an eARC HDMI connection. But that's hardly pressing. 

Nor is there any reason to connect a receiver/music streamer to these powered speakers that already require their own seperate volume control. First, because we mostly play records through those speakers, and also, because we can already stream Spotify to the speakers through our TV via an Ethernet cable connection, if necessary.

So yeah. It turns out that there can be  quite a difference -- at least theoretically -- between streaming music directly from the Internet versus via Bluetooth, and for the most part, both of these things carry less resolution than listening via CDs. This mostly comes down to data transfer rates. CDs can transmit something like 1.1 Mbps. Bluetooth hovers closer to 320 kbps at the high end. So at least theoretically, you're losing maybe 2/3 of your sound to compression via Bluetooth. But you can get at least some of that back by listening via direct Internet connection, i.e. Spotify Connect, etc., if you have a smart speaker or music streamer. Apple Music, Tidal, and a few others (not Spotify) offer actual HD-quality sound, though again, you'll probably need to connect via Ethernet cable to actually get all of that, and this assumes your home connection can even go that fast and that you have a good-enough speaker set-up to hear the difference.

You absolutely can hear the impact of music compression, though. SiriusXM uses the most compression of any music streaming service by far. So if you want to hear the actual impact that compression can make, stream any song over SiriusXM to a decent speaker and then stream that same song again via Spotify or Apple Music to that same speaker. You will totally hear the difference, especially if you're using a hard-wired connection.

Among other things, these speakers are seriously waterproof.

With all of this in mind, Sally and I set out to create a speaker system on our back deck. As Sally said, "Bluetooth speakers are fine, but I want something that's just there when we go out." We've been using a JBL Xtreme 2 as our primary back-deck speaker, and it's been entirely decent, so whatever we did next needed it to sound at least that good. 

This turned out to be a pretty serious benchmark.

We read tons of reviews and finally settled on Polk's Atrium 5 outdoor speakers. I was a little surprised to learn that outdoor speakers are mostly passive, but they are, so we also needed an amp. NYT's Wirecutter recommended the Fosi Audio BT20A Pro ($99), though if I had it to do over again, I might well go with the WiiM amp receiver/streamer all-in-one ($299). The Fosi is cheaper, obviously, and for an outdoor component, this seemed like a good trade-off. However, it doesn't have a built-in receiver/streamer, and adding one will cost something like $200, so...  

Still, I'm not sure how badly I want to leave a $300 component outside, even under our canopy. And yet, a receiver/streamer will probably be our next purchase, so maybe it's a moot point. That said, if we don't switch from Spotify to Apple Music, moving from a high-end Bluetooth connection to a direct streamer is probably also a moot point since Spotify and modern Bluetooth both transmit at something like 300 kbps.

Sigh.

I should note here that my friend Matt recommends connecting Fosi amps to the old Echo Dot 3.0 smart speakers via 3.5 mm aux cable. Which, of course, has me wondering what losses come associated with an aux cable, but what can you do? It's an interesting solution but probably not (much) better than just streaming via modern Bluetooth straight to the amp. The good thing about it, though, is that if you have several, you can connect them all wirelessly via your WiFi network. That's what Matt does, and it creates immersive sound across his entire backyard. However, he has a MUCH bigger back yard than we do.

Anyway. I set the Atriums up in the back corner of our canopy, directly over the couch. I didn't want to drill into the canopy, so I hung them with zip ties. 

One of the Polk Atrium 5 speakers hanging in my canopy.

They're perfect when you're inside the canopy, which serves as an ideal audio Engagement Area. However, directionality comes into play if you're sitting outside. You can certainly still hear these speakers, but the sound quality diminishes notably when you're not in line-of-sight of the speakers' output. It's aggravating because we often eat dinner out there but at the table not under the canopy.

Thankfully, the Fosi has a pre-out port if you want to send its output to a pre-amp or powered subwoofer. I've no idea why you'd want to do either -- who uses a dedicated outdoor subwoofer, and what would that even look like? -- but you can also connect that port to a simple aux cord, which we then connected to the JBL by way of reshaping the overall sound area. Doing this dramatically improved sound characteristics outside the canopy even though the JBL itself wasn't particularly loud. The effect was a lot like adding surround sound speakers. It doesn't hurt that this model JBL is known for having a lot of base. I mean, it's not a subwoofer, but it does a lot of the same kind of job here.

So far, we've watched quite a lot of TV and streamed quite a lot of music via Bluetooth through the new speakers. We've yet to connect our record player outside, but we chose this specific amp precisely because it has an RCA input and can connect to a turntable. So that's coming. I also want to try streaming music directly to the amp via the TV and not Bluetooth to see if I can hear the difference, but again, we've not done that yet, and if there is a difference, it ought to be quite subtle.

The one thing I'll do differently next time is to add some padding between the speaker bracket and the canopy itself to give the speakers a little more sonic isolation. I don't care enough right now to take the speakers down and rehang them, but that was an obvious trick that I didn't consider until I'd already gotten everything up and working.

Your thoughts?