Recently I tested the new SB Audience Bianco-15OB350 15" Open Baffle Woofer.
- Proprietary cone paper material made in-house
- Vented back plate for reduced compression
- 2.5" voice coil
- Designed for open baffle applications
I was recently commissioned to build open baffles for a customer who plans to install Kanzen Paladin field coil woofers. So prior to delivery I decided to test the open baffles (No.1549) with the SB Bianco 15OB350 woofers.
Open Baffle No.1549 Construction
The baffle measures 120cm x 120cm and is constructed from a combination of beech, oak, and baltic birch plywood.
Measurements
I conducted measurements outdoors. The following day I conducted measurements indoors in my main level living room. I currently do not have a dedicated listening room due to my business taking over floor space in my home.
Frequency Response (Outdoors)
I began with a frequency sweep at 1m. I was able to get good extension down to 40Hz however there is a dip at 65Hz. I am not sure what this was related to.
Burst Decay Response
Step Response
Distortion
I used a difficult multitone signal for my IMD test shown below. Test level was set to 90dB at 1 meter distance. Testing was done using a dynamic microphone which has lower distortion than my condenser mic. Distortion at 100Hz is -60dB down (0.10%). Distortion rises slightly starting at 1kHz (-50dB). Subjectively this woofer does well even up to 800Hz based on my listening tests.
Moving Indoors
I set the baffles up in my living room which has no acoustical treatment. The stereo pair of baffles were setup 1 meter from the rear wall and about 1.5 meters from the side walls. The microphone was placed at my listening position about 2m away. The response is shown below with no gating and 1/6 octave smoothing.
There is still considerable impact on the response from my room acoustics. Smoothing the response further to 1/1 octave produces the following graph.
The response in-room produces a substantial bass and mid-bass boost in relation to the midrange response. This is pretty close to my own personal preference especially for low listening levels.
Subjective Listening Impressions
I've experimented with open baffle in the past and the sound signature is the same. The only difference here is that these drivers produce the desired response with no equalization. I was able to easily integrate these drivers into a full range system with a simple second order low pass filter.
From the measurements we see that the bass extends down to about 50Hz and this is what it subjectively sounds like. While listening I couldn't help but think that a subwoofer could really help fill in the bottom end. However the overall presentation was large and dynamic completely across the frequency band. The clarity through this region kept up with the clarity of compression driver taking over at 800Hz. So pairing was very good with horns. The bass and mid-bass quality was excellent. Even into the 300Hz-800Hz range the sound was tactile and articulate. I was able to feel the music through my body. This was similar to the large ER electrostatic panels I tested a few months ago. There was also a better sense of soundstage depth through the 300Hz-800Hz region, and closely tied this sense of depth to the midrange and treble.
To summarize, I would highly recommend the SB Audience Bianco-15OB350 15" Open Baffle Woofer!