Audimax Bookshelf RD   Shelf speaker as in Hobby Hifi 3/2019

Technical data
  • impedance: 12 Ohm
  • sensivity (2,83V/1m): 81 dB
  • size (HxWxD): 440 x 220 x 340 mm
  • frequency range (-8dB): 33 - 30000 Hz
  • crossover frequency(s): 1700 Hz
  • speaker type: bass reflex

Audimax Bookshelf RD is a two way compact speaker.

Audimax Bookshelf RD is a bass-reflex cabinet loudspeaker with drivers of SB Acoustics and Hobby HiFi (Made by SEAS).

The kit is delivered with the following drivers:
- a SB Acoustics TW29R tweeter
- a Hobby-HiFi 18MW12T (Made by SEAS) woofer

The loudspeaker has been developed by Bernd Timmermanns.

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

The frequency response of this speaker is nearly linear.

The decay spectrum is perfect.

At medium volume, i.e. 90 dB at 1 m, the nonlinear distortions are below 1% above 100 Hz.

Our kit consists of

  • SB Acoustics tweeter SATORI-TW29R
  • Hobby-HiFi woofer 18MW12T, produced by SEAS
  • Jetset 70AT, bass reflex tube system, outer part
  • Jetset 70IT, bass reflex tube system, inner part
  • 0,5x Jetset 70MR, bass reflex tube system, middle
  • Jetset 70WR (angle tube)
  • 0,5x Damping Sonofil 100 x 35 cm for 20 litres
  • 0,5x Audaphon Damping 10, 970 x 470 mm, adhesive
  • Binding Post PK31, gold plated (one pair, red and black)
  • 2m Speaker cable 2x2.5 mm2, transparent
  • 1,5x Pan screws 4x20 black, torx, 8 pieces
  • Plan for DIY kit

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

  • Mundorf MCAP EVO Oil 0.22 uF / 450 V
  • Mundorf MCAP EVO Oil 2.2 uF / 450 V
  • Mundorf MCAP EVO Oil 3.3 uF / 450 V
  • Mundorf MCAP EVO Oil 4.7 uF / 450 V
  • Mundorf MCAP EVO Oil 10 uF / 450 V
  • Mundorf baked varnish air core coil BL71, 0.47 mH/0.57 Ohm
  • Mundorf baked varnish air core coil BL71, 0.68 mH/0.71 Ohm
  • Mundorf baked varnish air core coil BL140, 4.7 mH/0.83 Ohm
  • Metal-oxide resistor, 10W 10 Ohm (brown-black-black)
  • 2x Metal-oxide resistor, 5W 1.0 Ohm (brown-black-gold)

Kit without cabinet, price per speaker   EUR 738,00 excl. VAT: € 620.17 / $ 694.59

Kit with high-end crossover

The high-end kit is delivered with baked varnish air core coils or copper foil 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 SB Acoustics TW29R are of type polypropylen (MKP) Clarity-Cap CSA 630V.

Kit with high-end-crossover without cabinet, price per speaker   EUR 833,00 excl. VAT: € 700.00 / $ 784.00

Kit with other tweeters

We also offer the Audimax Bookshelf RD kit with three different alternative tweeters suggested in Hobby HiFi. The quality of the crossover parts is in all kits the same like the RD version. Only the crossover values in the kit with the Wavecor TW030WA10 are a little different.

Kit with SB Acoustics SATORI TW29B (Beryllium) without cabinet, price per speaker   EUR 891,00 excl. VAT: € 748.74 / $ 838.59

Kit with SB Acoustics SATORI TW29B (Beryllium) with high-end-crossover without cabinet, price per speaker   EUR 986,00 excl. VAT: € 828.57 / $ 928.00

Kit with Scan Speak D3004/662000 without cabinet, price per speaker   EUR 815,00 excl. VAT: € 684.87 / $ 767.06

Kit with Scan Speak D3004/662000 with high-end-crossover without cabinet, price per speaker   EUR 910,00 excl. VAT: € 764.71 / $ 856.47

Kit with Wavecor TW030WA10 without cabinet, price per speaker   EUR 673,00 excl. VAT: € 565.55 / $ 633.41

Kit with Wavecor TW030WA10 with high-end-crossover without cabinet, price per speaker   EUR 777,00 excl. VAT: € 652.94 / $ 731.29

Impedance correction

If you want to use a valve amplifier with this speaker an impedance correction should be employed. In this case the component quality is less important; therefore, we offer only one kit (upon request higher quality components are available).


Price per impedance correction for one speaker, to be mounted on a small wooden board.     EUR 34,45 excl. VAT: € 28.95 / $ 32.42

universal PCB

If you prefer to mount the crossover components on a 159 x 127 mm universal PCB instead on wood:
Universal PCB RA160, order no.. I-2766, price per unit:   EUR 5,10 excl. VAT: € 4.29 / $ 4.80
We recommend two boards per kit (four boards for a speaker pair)


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