Technical specifications
Dimensions 
Weight 
Battery type 
Battery life 
Ext. mic./Aux in connector 
MicroSet
TM
/headphones conn. 
Volume control 
Tone control 
Power switch 
Mic and T-mode 
Ext. mic / Aux in accessories
MicroSet
TM 
accessory
R/L-channel balance setting
Maximum volume setting
Dynamic compressor
Dynamic noise reduction
Feedback cancellation
Digital signal processing
Acoustic specifications
Output level with BE9122
Ref. test gain
Output level
 with BE9125
Ref. test gain
Electrical specifications
Output power 
Distortion 
SNR 
Frequency response
Aux in sensitivity (max input lvl.)
140 x 45 x 27 mm (L x W x T) 
133 g (including batteries) 
Two ”AA”-size alkaline cells 
Up to 150 h
2.5 mm stereo telejack 
3.5 mm stereo telejack 
9 steps (5 dB/step) 
5 pre-set steps, push-buttons 
on-off toggle button 
Separate mode select buttons 
Automatically selects Aux in or 
ext. mic. when plugged in 
Automatically selects MicroSet™ 
accessory 
when plugged in
0-20 dB programmable attenua
-
tion (in steps of 5 dB) 
0-21 dB programmable attenua
-
tion (in steps of 3 dB) 
10 channels
Dynamic gain range:  0-35 dB 
Compression:  3:1 
Expansion:   1:1.5 
Attack time:    25 ms 
Release time:    250 ms
10 channels Adaptive frequency 
domain noise reduction
Adaptive time domain feedback 
cancellation
19.948 kHz sampling frequency 
16-bit resolution in stereo
IEC 118-0
117.67 dB @ 1 kHz (SPL90)
119.52 dB (HF Ave. SPL90)
29.21 dB (SPL70)
134.85 dB @ 1 kHz (SPL90)
130.89 dB (HF Ave. SPL90)
38.9 dB (SPL70)
125 mW/channel (@ 16 Ohm load)
0.559 % THD 
82 dB 
40 Hz – 10 kHz
Tone, high: +10dB@3.15 kHz
-6dB@250Hz Tone, mid: flat 
Tone, low: -10dB@3.15 kHz 
No bass boost
+6 dBV
Features
 Digital signal processing
 Omni-directional electret condenser microphone
 Telecoil pickup for inductive loops 
 10 channel dynamic range compressor
 10 channel dynamic noise suppression
 Adaptive feed-back manager
 Intuitive user interface 
 ▪ LED lightbar for excellent readability 
 ▪ 9 step volume control (5 dB/step) 
 ▪ 5 step tone control 
 ▪ Mic and T-mode indicator 
 ▪ Low battery warning indicator
 Auxiliary stereo signal input (2.5 mm telejack)
 Headphones stereo output (3.5 mm telejack)
 Push-To-Listen mode (Int. mic and Aux in mixed)
 Soft-mute when switching between signal sources
 Advanced settings 
 ▪ L/R channel balance control (5 dB/step) 
 ▪ Maximum volume control (3 dB/step) 
 ▪ T-coil selector lock (on/off)
 Requires no individual fitting
 Powered by two AA-size alkaline batteries
 Transparent belt clip
Noise cancellation
Noise cancellation operates in frequency-domain and uses ten channels to continuously analyse and attenuate stationary noise.
The noise cancellation dynamically adjusts the gain for each frequency band to give an optimal dynamic range, thus suppressing noise 
without affecting speech or other interesting information.
Noise is suppressed with 5 dB without sacrificing resolution or intro
-
ducing sound artefacts, which increases the listening comfort.
Dynamic range compression
The dynamic range compressor operates in the frequency-domain 
and is implemented as 10 channels, logarithmically. 
Each channel has individual attack/decay, expansion, compression 
and saturation distance parameters, which have been trimmed to 
reduce microphone noise, emphasise speech or other interesting 
information and still offer a natural sound.
The personal amplifier should not need individual fitting nor user 
selectable programs, which means that the parameter settings have 
been preset from factory.
Feedback cancellation
The feedback cancellation operates in the time-domain by continuously analysing the signal to detect pure tone within a certain fre
-
quency range, since they may indicate a build-up of feedback.
The adaptive algorithm estimates the feedback potential (path) of 
the amplifier and can accurately (in magnitude and phase) eliminate 
the feedback cause even before the whistling occurs. 
The algorithm reacts quickly to any change in the feedback path caused by moving. Feedback cancellation works for different posi
-
tions of the headphones (near the amplifier as well as away from it).
The feedback cancellation provides the user with 10 dB additional 
gain, which is beneficial when using open type headphones (or other 
open fitting transducers).
Battery level supervision
The supervision of the battery voltage level is continuously operating in the background, making one measurement every 10th second. 
The result of the measurement is presented to the user by means of 
the Low Battery indicator (Amber LED).
The battery supervision indicates a Battery Low condition when the 
estimated remaining battery time is around 10 hours.
When the battery is almost depleted the battery supervision shuts 
down the amplifier in an controlled manner, to avoid unpleasant 
sounds or malfunction due to abrupt power loss. The amplifier noti
fies the user about this action by three quick consecutive flashes of 
the Low Battery indicator before it shuts down.
Frequency response/tone control
BE2020_008DAS_001_EN © Bellman & Symfon AB 2008