P-6.5 Passive radiator 17,5 cm / 6.5 "with variable weights   

The main advantages are:
1. No space problem with reflex tubes in compact housings and no flow losses
2. No tube / breathing noise
3. No midrange audible outside
4. The P-6.5 is tunable by 3 removable weight plates

The hard anodized aluminum membrane weights of 20 g. The 3 discs weigh 20 g each and can be removed. To do this, turn the rear nut to the left with a pair of long flat-nose pliers.

Attention:
The screw at the front and the nut directly at the back of the membrane are firmly glued - please do not remove!
The effective membrane weight can now be adjusted with the 3 discs. For special fine tuning you can cut use smaller disk or screw or other weights.
When tuning by ear, firstly test with 3 discs, which fits our D-165 subwoofer speaker chassis in below HiFi ULTRA-SUB. For further improvement with DSP we recommend our DSP-6mini. Its 3 stereo channels can also control the midrange and treble range (link) funktioniert nicht. For lighter and smaller main speakers, reduce the discs until the low bass sounds best.
When tuning according to the measured impedance curve, both impedance maxima should be the same.
10 cm loudspeakers are combined with P-6.5 without disc, 13 cm loudspeakers and lighter 16 cm diaphragms fit 1-2 discs.

Rule of thumb:
Heavy passive membrane = balanced and deep bass - lighter passive membrane = louder, but not so deep bass.
For 2-3 weights, we recommend turning the P-6.5 by 180 ° every year, so that the rubber edge is loaded more evenly