Nidda Shelf speaker as in K+T 5/2024

Technical data

impedance: 4 Ohm
sensivity (2,83V/1m): 85 dB
size (HxWxD): 260 x 185 x 170 mm
frequency range (-8dB): 48 - 38000 Hz
crossover frequency(s): 95, 2700 Hz
speaker type: bass reflex

Nidda is a three way sub-sat system.

Nidda is a bass-reflex cabinet loudspeaker with drivers of BlieSMa and Accuton.

Dimensions of Nidda subwoofer: (HxWxD): 640 x 260 x 380 mm

Dimensions of Nidda Satellite: (HxWxD): 260 x 185 x 170 mm

The kit is delivered with the following drivers:
- two BlieSMa T25B-6 tweeter
- two Accuton C158-6-851-FG mids drivers
- two Accuton S220-6-224-FG woofers

The loudspeaker has been developed by Dennis Frank and Daniel Gattig.

The crossover consists of:
- a 2nd order high-pass filter (12 dB per octave slope) for the tweeter.
- a band pass consisting of a 2nd order high pass filter (12 dB per octave slope) and a first order low-pass filter (6 dB per octave slope) for the mids-woofer.
- a 3rd order low-pass filter (18 dB per octave slope) for the woofer.

The frequency response of this speaker is nearly linear.

The decay spectrum is nearly perfect.

At low volume, i.e. 85 dB at 1 m, the nonlinear distortions are below 0,5% above 300 Hz and doesn't exceed 0,6% at 95 dB at 1 m between 300 and 15000 Hz.

An excerpt from the Klang+Ton review (Translation of the author into English)

Conclusion of the magazine Klang+Ton:

Our kit consists of

2x Accuton C158-6-851-FG mids/woofer, one unit
2x Accuton S220-6-224-FG woofer, one unit
2x BlieSMa T25B-6
4x Bass reflex tube HP70, 70x220m, black
3x Damping fleece MT Bondum 800 (30 x 50 x 2 cm)
6x Binding Post PK28 I, gold plated (one pair, red and black)
2m Speaker cable 2x1.5 mm2, transparent
2,5x Pan screws 3.5x17 black, torx, 8 pieces
1,5x Allen wood screws, black, 4x25 mm, 8 pieces
Plan for DIY kit

the crossover components (right),
to be mounted on a small wooden board.

2x Audaphon MKP CAP Superior 1.0 μF / 400 Vdc
2x Audaphon MKP CAP Superior 1.8 μF / 400 Vdc
2x Audaphon MKP CAP Superior 22 μF / 400 Vdc
2x Audaphon MKT CAP 2.2 μF / 160 Vdc
4x Audaphon MKT CAP 100 μF / 160 Vdc
2x Mundorf, electrolytic capacitor, etched, 470 μF/63 Vdc
2x Mundorf, electrolytic capacitor, etched, 560 μF/63 Vdc
2x 1.4 mm air core coil, 1.0 mH/0.29 Ohm
2x 0.7 mm air core coil, 0.56 mH/0.55 Ohm
2x 0.7 mm air core coil, 0.68 mH/0.70 Ohm
2x Mundorf bs125 core coil 12 mH/0.51Ohm
2x Mundorf H core coil H71, 4.7 mH/0.46 0hm
2x Mundorf H core coil H71, 10 mH/0.87 0hm
2x Mundorf H core coil H100, 3.3 mH/0.27 0hm
2x ceramic resistor 1.0 Ohm/20 Watt
4x ceramic resistor 18 Ohm/20 Watt
2x Metal-oxide resistor, 10W 2.7 Ohm (red-purple-gold)
2x Metal-oxide resistor, 10W 8.2 Ohm (grey-red-gold)

Kit without cabinet, price per set EUR 4434,00 excl. VAT: € 3726.05 / $ 4098.66

Kit with high-end crossover

The high-end kit is delivered with baked varnish air core coils on important parts of the crossover for minimizing microphonic effects. - The current flow through the coil creates a magnetic field which sets the reel of wire in motion. This motion induces a voltage in the coil which adds itself to the signal. The stiffer the reel of wire is, the less the signal will be altered. The capacitors for the BlieSMa T25B-6 are of type polypropylen (MKP) Clarity-Cap CMR 630 V.

2x ClarityCap CMR capacitor 1.0 μF / 630 Vdc
2x ClarityCap CMR capacitor 1.8 μF / 630 Vdc
2x Mundorf MCAP EVO 220 μF / 250 V
2x Mundorf MKP capacitor 2.2 μF / 400 V
2x Mundorf, electrolytic capacitor, etched, 470 μF/63 Vdc
2x Mundorf, electrolytic capacitor, etched, 560 μF/63 Vdc
2x Mundorf baked varnish air core coil BL71, 0.56 mH/0.64 Ohm
2x Mundorf baked varnish air core coil BL71, 0.68 mH/0.71 Ohm
2x Mundorf baked varnish air core coil BL140, 1.0 mH/0.30 Ohm
2x Mundorf bs125 core coil 12 mH/0.51Ohm
2x Mundorf H core baked varnish coil BH71, 4.7 mH/0.55 0hm
2x Mundorf H core baked varnish coil BH71, 10 mH/0.87 0hm
2x Mundorf H core baked varnish coil BH100, 3.3 mH/0.26 0hm
2x ceramic resistor 1.0 Ohm/20 Watt
4x ceramic resistor 18 Ohm/20 Watt
2x MResist Supreme 8.2 Ohm / 20 Watt
2x Mresist Classic 2,7 Ohm / 10 Watt

Kit with high-end-crossover without cabinet, price per speaker EUR 4964,00 excl. VAT: € 4171.43 / $ 4588.57

universal PCB

If you prefer to mount the crossover components on a universal PCB instead on wood
PCB 220x155 mm, order no. I-8805002, price per unit: EUR 11,80 excl. VAT: € 9.92 / $ 10.91
We recommend two boards per kit
PCB 150x115 mm, tin plated, price per unit: EUR 4,70 excl. VAT: € 3.95 / $ 4.34
We recommend a half board per kit (half per satellite)