SB Acoustics Ara Beryllium Speaker Kit

Introduction

Welcome to Part II of the SB Acoustics Ara Speaker Kit review. This article covers the assembly process of the speaker kit, an upgrade to the Beryllium tweeter, and our very first episode of "Pimp my Speaker" !

Description

A short walk back to the initial article of the SB Acoustics Ara Speaker Kit review would be useful to understand the speaker in depth. For now, let's have a look at the assembly and tweaking process.

Assembly of the speaker kit is quite easy for anyone with some DIY experience. I would not however recommend it for first timers as decent soldering experience is required, and the speaker driver units are quite expensive - one slip of your screwdriver is all it takes to destroy them.

Assembly

My kit came with fully assembled cabinets and crossover boards. The crossover board is wired with their leads terminated in push-on clips for the drivers, and tinned leads for the binding posts. 

The most tedious part of the assembly would be the cutting of the fiberfill pads to size, and pushing / gluing everything into place. The crossover board can be a bit tricky to install though, as you need a short stubby cross head screwdriver to attach the board to the base of the cabinet. In my case, one of the cabinets did not have any pre-drilled guide holes and I had to hammer the screws into the cabinet to make my own guide holes.

The rest of the hook-up process is quite idiot-proof. The push on clips are sized to match the terminals of the speaker drive units, so you can't install them in reversed polarity. I also liked the fact that the holes for the binding post plate and both drivers had metal thread inserts - no more stripped MDF, and you can torque the bolts with confidence (but not gorilla strength please !). The length of the supplied cables were generous and you do not need to be a contortionist or Octopus to attach the wires to either the binding post or the speaker drivers. The binding post leads do need to be soldered though - the only time your soldering iron will get any action. A glue gun is also required to seal the guide holes where the crossover board wires connect to the binding posts, or you could use your imagination to seal them in any other way you deem fit.

Pimp My Speaker

Good Audiophiles like to milk every ounce of performance out of their gear and DIY equipment are a great way to express and showcase your creativity and talent. I installed the crossover board on top of the speaker, and extended the leads using Belden wire and terminals blocks. The speakers were given about 10 hours of run-in time in between each stage of modification unless otherwise indicated.  

Part 1 - Replace the sandcast resistors with Ohmite and Mills resistors

Nothing fancy used here - just wirewound Ohmite and Mills MRA-12 resistors. The latter have non-inductive windings. Despite their specified tolerances, all of the resistors measured very closely, within +/- 0.1 ohms of their stated values.  

The stock resistors are "thoughtfully" glued into place. Brute force is required here to detach the resistors from the board. 

There is a slight but noticeable improvement here, with an uplift in clarity and reduction in grain. 

Part 2 - Replace the plastic capacitors with Auricap XO film capacitors

The stock Jantzen Cross Caps supplied are quite decent, but the Auricaps are well worth the expense. The Auricaps improve clarity and lend an extra level of dimensionality and detail to the speakers. In comparison, the Jantzen sound flatter and drier. 

Stock crossover board in the middle of surgery

All complete except for the wires

Part 3 - Replace the speaker drive unit leads with Neotech OCC cables, and the binding posts with Furutech.

I used 20 AWG Neotech Pure Silver solid core OCC wire for the tweeters, and 16 AWG multi strand copper OCC cable for the woofers. I am not really fond of push-on terminals, and soldered the cables directly to the drive unit terminals.

The initial impressions were quite negative, with the speaker losing both drive and vitality. These cables use Teflon insulation, which have a reputation for long run-in time -  I put in 48 hours of run-in here. Post run-in, the cabling provided a higher level of refinement and micro-detail. The stock wiring has a more forward and incisive sound, but in terms of layering and staging, the Neotech is noticeably better. The Furutech FP-803B(G) binding posts just happened to be lying around - the stock posts would do just fine.  

I would rate the capacitor upgrade as the most effective, followed by the internal wiring upgrade. The resistors and binding posts could be left alone, unless you are the sort that leaves no stone unturned. Actually even with the stock crossover board, the performance level is already very high. 

Comparisons

The Beryllium tweeter is well worth the upgrade in my opinion. In my earlier article, I pointed at a slight discontinuity between the two drive units, and a prominence to the tweeter that called a bit of attention to itself. There were no such issues with my personal build (the version I heard used the silk dome crossover board with some modifications). I would only recommend the fabric dome version if budget is tight, or you have a dislike for extended high-frequencies.

If you felt that the base level kit was great value, this premium version will have the competition running scared - it's that good !