Visaton GF 200

[Helmuth]

Originally posted by Inductor


That is very good to know, Helmuth. Thanks. There is a lot of defective parts in the market. (Some factories/shops are not in business any more). And I guess they come to the market as new items, (in this case) a sample is never tested and/or their manufacture quality is poor. Sometimes it pays to have a shop around the corner.

Precise Inductor,

The Monacor are assembled in Taiwan the materials are O.K only by poor quality control every thing can go wrong.

Till I used the Monacor I always had Visaton. I can say with visaton no quality problems a very good firm.


Regards, Helmuth

[Bill poster]

Question about this woofer -
if using one voice coil (4ohms)
Fs 34hz
qts 0.77
vas 62L
when I model it on winisd in a sealed 45 litre it gives some interesting results, a slight hump (+2db@ 60-80hz) and an F3 of a very respectable 38hz before dropping quite quickly. More importantly, the qtc is 1.18, and 40 litres is 1.22. Any issues with stuffing a high qtc/vas driver in a smaller enclosure?

[Dissi]

The peak can somewhat be corrected by an appropriate serial capacitor. In this case it's a large 2200uF. The result in a 42 liter box without baffle step:
VisatonGF200InfiniteBaffle.jpg
The red curve should be close to your simulation. And now with baffle step simulation switched on:
VisatonGF200Baffle.jpg

[mondogenerator]

a while ago i posted my 1st sub thread. I was trying to decide on a subwoofer and both visaton TIW200XS, 250XS and GF200 were on the choices amongst others. In WinISD the TIW drivers disappoint me a little so I looked at the GF200 due to the dual voicecoil providing Qts 'tuning'. Running a single voicecoil makes for an interesting sealed box speaker. Resistive adjustment of Q could be done with the other coil, which could improve the concept further. Nice looking driver and i trust the company quality.

[Bill poster]

65813.jpg

Hmmm, would make a possible isobaric candidate, being able to reduce that sealed area.. would the above work?

[mondogenerator]

Indeed Bill, the 2 ohm parallel impedance is what stopped me persuing isobaric designs, since 4 ohm is the lowest id be happy running with my amp. For others it may be less of an issue. I should really do the math for using a resistor on the 2nd coil. If i can lower Qts, even to 0.6 then that would make the driver a little easier to work with.