Celeste Koax   Floorstanding as in Hobby Hifi 3/2020

Technical data
  • impedance: 6 Ohm
  • sensivity (2,83V/1m): 92 dB
  • size (HxWxD): 620 x 440 x 310 mm
  • frequency range (-8dB): 45 - 20000 Hz
  • crossover frequency(s): 2200 Hz
  • speaker type: bass reflex

Celeste Koax is a two way compact speaker.

Celeste Koax is a bass-reflex cabinet loudspeaker with drivers of Celestion .

The kit is delivered with the following drivers:
- a Celestion TF1225CX coaxial driver

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 part of the coax loudspeaker.

The frequency response of this speaker is nearly linear.

The decay spectrum (waterfall spectrum) shows a decelerated swing-out behaviour in the mid-range.

At medium volume, i.e. 90 dB at 1 m, the nonlinear distortions are below 0,9% above 200 Hz.

Our kit consists of

  • Celestion TF1225CX (Coaxial), 97dB, 40Hz-18kHz
  • Damping 30 1100 x 470 mm, adhesive
  • 0,5x PE sealing tape, 5x2 mm, 7.5 m
  • Binding Post PK31, gold plated (one pair, red and black)
  • 2m Speaker cable 2x2.5 mm2, transparent
  • 0,5x Allen wood screws, black, 5x30 mm, 8 pieces
  • Plan for DIY kit

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

  • Audaphon MKP CAP Superior 2.7 μF; / 400 Vdc
  • Audaphon MKP CAP Superior 4.7 μF; / 400 Vdc
  • Audaphon MKP CAP Superior 6.8 μF; / 400 Vdc
  • Mundorf, electrolytic capacitor, etched, 150 uF/63 Vdc
  • Mundorf, electrolytic capacitor, unetched, 22μF / 70 Vdc
  • Mundorf baked varnish air core coil BL71, 0.33 mH/0.48 Ohm
  • Mundorf baked varnish air core coil BL71, 12 mH/3.9 Ohm
  • Mundorf baked varnish air core coil BL140, 1.2 mH/0.34 Ohm
  • Mundorf baked varnish air core coil BL140, 2.7 mH/0.51 Ohm
  • Metal-oxide resistor, 10W 2.2 Ohm (red-red-gold)
  • Metal-oxide resistor, 10W 3.3 Ohm (orange-orange-gold)
  • Metal-oxide resistor, 10W 4.7 Ohm (yellow-violet-gold)
  • Metal-oxide resistor, 10W 6.8 Ohm (blue-grey-gold)
  • Metal-oxide resistor, 10W 10 Ohm (brown-black-black)

Kit without cabinet, price per speaker   EUR 412,34 excl. VAT: € 355.47 / $ 415.89

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 Celestion TF1225CX, where high quality is required, are of type polypropylen (MKP) Mundorf EVO Öl 450 V.

  • Mundorf MCAP EVO Oil 2.7 μF; / 450 V
  • Mundorf MCAP EVO Oil 6.8 μF; / 450 V
  • Mundorf MCAP EVO Oil 27 μF; / 450 V
  • Audaphon MKP CAP Superior 22 μF; / 400 Vdc
  • Mundorf, electrolytic capacitor, etched, 150 uF/63 Vdc
  • Mundorf baked varnish air core coil BL71, 0.33 mH/0.48 Ohm
  • Mundorf baked varnish air core coil BL71, 12 mH/3.9 Ohm
  • Mundorf baked varnish air core coil BL180, 1,2 mH/0.22 Ohm
  • Mundorf baked varnish air core coil BL180, 2.7 mH/0.39 Ohm
  • Mresist Classic 4,7 Ohm / 10 Watt
  • Mresist Classic 6,8 Ohm / 10 Watt
  • Metal-oxide resistor, 10W 2.2 Ohm (red-red-gold)
  • Metal-oxide resistor, 10W 3.3 Ohm (orange-orange-gold)
  • Metal-oxide resistor, 10W 10 Ohm (brown-black-black)

Kit with high-end-crossover without cabinet, price per speaker   EUR 500,07 excl. VAT: € 431.09 / $ 504.38

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).

  • Mundorf, electrolytic capacitor, unetched, 8.2 μF; / 70 Vdc
  • Mundorf, electrolytic capacitor, unetched, 47μF / 70 Vdc
  • Mundorf baked varnish air core coil BL71, 0.33 mH/0.48 Ohm
  • Mundorf baked varnish air core coil BL71, 2.2 mH/1.3 Ohm
  • ceramic resistor 8.2 Ohm/20 Watt
  • ceramic resistor 10 Ohm/20 Watt

Price per impedance correction for one speaker, to be mounted on a small wooden board.     EUR 32,75 excl. VAT: € 28.23 / $ 33.03

universal PCB

If you prefer to mount the crossover components on a 240 x 165 mm universal PCB instead on wood:
Universal PCB RA240, order no.. I-2767, price per unit:   EUR 7,41 excl. VAT: € 6.39 / $ 7.47
We recommend one board per kit (two boards for a speaker pair)

Additionally needed 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 4,97 excl. VAT: € 4.28 / $ 5.01
We recommend a half board per kit (one board for a speaker pair)


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