MOX builder’s thread

[JensRasmussen]

Thank you for the information about the name of the jumper. Webpage and manual are now updated.

\Jens

[jewilson]

Jens

Are these active filters PCB's still available at the web address.
http://www.anidian.com/audio/construct/mox.shtml

Thanks

[JensRasmussen]

HI,

I don’t know how many boards Tyler have left. If there are any left I’m sure you can bye some from Tyler.

\Jens

[tiroth]

Originally posted by jewilson
Are these active filters PCB's still available at the web address.
http://www.anidian.com/audio/construct/mox.shtml

Yes, I still have some left and the order form works. The 2SK389 are marked OOS but I actually got ahold of a few more, so shoot me an email if interested.

[jewilson]

tiroth

Yes I am interested; I also have some friends that will be interested too. I have been considering building an active crossover for while but using discrete amps instead. However, like so may other things I don't have the time. But I have the amps.

[chipco3434]

I'm not willing to kit out all the resistors though. Chipco3434, are you serious about doing this? If so, it would make much more sense to have the caps sent to you.

Sorry to have stepped out of the thread for a while... Sadly, I have been obliged to W*RK. (Moderators...sorry for the four letter word!)

Few people have really bit on this thread. It seems as the most tedius part of this project is typing in the part numbers for ordering!

I would be happy to distribute those surplus caps from Jens ( for the cost of the shipping) to all the audio junkies in North America.

Of course, I would be happy to forward Jens the money for the shipping. (Via Paypal I would assume.)

So, kick it arround.

[BDP]

I have assembled and tested the discrete opamp and all have checked out good. When the first opamp was assembled on the circuit board and power and other leads were breadboarded it oscillated. YIKS? Whats going on??. I regrouped shortened my test leads and now it works. The bandwidth of the follower with 68pF cap for C2 is 5MHz. 100pF was about 4MHz.
I have also used a P-channel MOSFET, a Zetex ZVP3310, in place of PNP MPSA 92. I used a 5K fixed resistor parallel with a 10K pot. at R3 and R4 in order to adjust for zero DC offset. The value of the drain resistance worked out to be 1850 ohms , but this value will vary depending on the ZVP 3310 used, that is if you want a low DC offset. Initially the drain resistance R3 used was 1500 ohms and the DC offset was 230 mV. I also added a 100 ohm gate resistor to the mosfet just for good measure to prevent oscillation.

I have no doubts that the circuits will work when installed in the MOX filter boards.

BDP

[tiroth]

Originally posted by chipco3434
I would be happy to distribute those surplus caps from Jens ( for the cost of the shipping) to all the audio junkies in North America.

Jens sent them out to me just the other day; as soon as they arrive I'd be happy to send them out to anyone who is interested.

[jhead]

I would be interested in a set for the MOX please let me know thanks

[tiroth]

I have the caps. Thanks Jens!

Anyone who wants some, please send me an email and include

• your name
• your address
• the number of caps you need

Thanks.