ScanSpeak-Soundbar

DIY Loudspeakers: HOME INDEX UPDATES RESPONSE WHAT'S NEW

ScanSpeak Soundbar
Copyright 2024 © Troels Gravesen

Go to on this page:

DRIVERS CROSSOVER CABINET WORKSHOP PICS MEASUREMENTS SPEAKER-KIT CROSSOVER LAYOUT

Jann Evers, Director of Sales, ScanSpeak, asked me to do a soundbar for their exhibition at Soundsociety 2024 in Copenhagen. A task well received, as I had for long wanted to improve the sound from our own TV. Jann had tested the ARYLIC B50 amplifier at home and found it to deliver excellent sound - not least taking the price into consideration; I mean 140 EUR here in Europe...

Now, soundbars usually require fairly small speaker drivers, thus I picked the 12W drivers from the ScanSpeak Discovery line. I've used these drivers before and was always impressed by the magnificent midrange reproduction. Here we use 2 pcs 12W/8524G00 in parallel and we can manage a system sensitivity around 89 dB, quite nice for such small speaker. And even at this tuning they do some bass, F3 = 65 Hz. Two times 12W makes some 118 cm^2 membrane area, equivalent to an SBA MW16 driver, so not so small after all.

For treble, well, the choice was obvious having tested the new Illuminator tweeter D3004/602200. Maybe a little expensive here, but actually the only one having a suitable small faceplate. I can only say that I'll be using the tweeter some other time in more conventional hifi speakers, that's how good it is.

A friend came by having Qubuz on his iPhone and we made the bluetooth connection - really some enjoyable moments, suggesting a small stereo setup with some impressive bass performance coming from the small 4" midbass drivers.

Basics:
3-driver speaker.
Dimensions: 112 x 20 x 16.5 cm, WxDxH.
System sensitivity: ~89 dB/2.8V/1 meter.
Impedance: 4-8 Ohms.
Power requirement: 20+ watts/channel.

Useful links (Please follow all links before e-mailing!):
http://www.troelsgravesen.dk/tips.htm
http://www.troelsgravesen.dk/tips.htm#CONSTRUCTION_OF_CROSSOVERS
http://www.troelsgravesen.dk/crossovers.htm
http://www.troelsgravesen.dk/LCR-RC.htm
http://www.troelsgravesen.dk/Inverted-Polarity.htm
http://www.troelsgravesen.dk/choices.htm

DRIVERS
BACK TO INDEX

Download specs here: 12W/8524G00 D3004/602200

CROSSOVER
BACK TO INDEX

The crossover features an LR4 topology at around 2.5 kHz.

CABINET
BACK TO INDEX

Cabinets were made from 15 and 19 mm black MDF (HDF/Valchromat), 19 mm for top and bottom. Front panel may be tilted ~10^o, if so, keep 200 mm depth of middle of cabinet. This makes 185 at top and 215 at bottom.
Ports are 145 x Ø50 mm.

Workshop pics
BACK TO INDEX

Soundbar seen from front with center placement of Arylic amplifier.
I sanded the cabinet and polished with beeswax.

Soundbar seen from rear with rear panels removed.

Place crossovers on rear panel and connect to terminals.

Connect 12W drivers and parallel.

Stuff cabinet with 60 grams of sheeps wool.

The ARYLIC blue-tooth amplifier.

https://www.arylic.com/products/b50-bluetooth-stereo-amplifier

This amp pretty much does everything...even MM phono input.

Download app by scanning the code found in the instruction following the amp and you have it all in the palm of your hand.

Using the line-in from my EAR-868PL, I have to say this amp sounds surprisingly good. I'm impressed.
The midrange driven from my EAR-861 was so good I was thinking of using two of the same in a classic 3-way, why not 2 x 12W mated with the 6022 tweeter and a suitable 10" bass driver?

MEASUREMENTS
BACK TO INDEX

A few comments on MEASUREMENTS before you start interpreting the readings below.
First of all, if we think measurements will tell us how a speaker sounds, we're wrong. The perception of sound is way too subjective to be reflected in any measurements we can perform. A loudspeaker system is meant to give us a satisfying idea of an acoustic event and for some people a pair of 5 USD ear-plugs are enough, others spend 200 kUSD on a truly full-range pair of speakers - and the latter may not be happier than the former.
Measurements may give us an idea of tonal balance of a system, i.e. too much or too little energy in certain areas, although dispersion characteristics play a vital role here. A two-way 7+1 and a three-way 7+4+1 may display similar horizontal dispersion, yet sound very different. Measurements may tell us about bass extension if far-field measurements are merged with near-field measurements. In addition to this, ports may contribute to bass extension. Most of we diy'ers do not have access to an anechoic room for full-range measurements from 20-20000 Hz.
What cannot be seen is what kind of bass performance we get in a given room. Bass performance is highly dependent on in-room placement of your speaker and the same speaker can be boomy in one place and lean in another. Actual SPL level at 1 meter distance and 2.8V input is useful for en estimate of system sensitivity and combined with the impedance profile may give an idea of how powerful an amplifier is needed to drive the speaker to adequate levels.
What measurements do not tell is the very sound of the speaker unless displaying serious linear distortion. The level of transparency, the ability to resolve micro-details, the "speed" of the bass, etc., cannot be derived from these data. Distortion measurements rarely tell much unless seriously bad, and most modern drivers display low distortion within their specified operating range.
Many people put way too much into these graphs and my comments here are only meant as warning against over-interpretation. There are more to good sound than what can be extracted from a few graphs. Every graph needs interpretation in terms of what it means sonically and how it impacts our choice of mating drivers, cabinet and crossover design.
What measurements certainly do not tell is the sonic signature of the speaker, because speaker cones made from polypropylene, aluminum, Kevlar, paper, glass fiber, carbon fiber, magnesium, ceramics or even diamonds all have their way of adding spices to the stew. Nor do measurements tell what impact the quality of the crossover components add to the sound, from state of the art components to the cheapest of coils and caps, they all measure the same if values are correct, yet sound very different.

SPL at 0.5 meter normalised for 2.8V/1 meter.
I left the slight increase in upper octave unattended, adds a bit of airiness to the sound. The 6022 tweeter has an inherent increase in response towards 20 kHz.
Actually we have some 89 dB sensitivity.