Jensen 4 pole advantage cannot be used in coupling application, so no traces need to be cut; just install it as any other cap, the amp board is ready for it 😉
Flecko said:
You can use any value for C1 as long as it won't be acting as a high pass filter.
For instance, with my 4 ohm FAL drivers, I'm using presently BG N 330/100 and a cut off frequency is approx 120Hz.
With 8 ohm drivers and 2200uF cap (for C1) the cut off frequency is approx 9Hz. It will double for 4 ohm.
So 15000 uF is basically overkill for most applications ?
What about in terms of DC blocking capabilities ? Would too small a coupling capacitor pose any threat to the speakers ?
What about in terms of DC blocking capabilities ? Would too small a coupling capacitor pose any threat to the speakers ?
The capacitance value is not critical for coupling safety: I'm using a single 6.8uF in a tweeter network. The voltage rating is important though, and with this amp should be at least 63V.
Peter,
Boards arrived - excellent quality, as usual - thanks for adding the updated Cct diagram with the good packing, and also for all the efforts to make these boards available, Many thanks - much appreciated.
James
Boards arrived - excellent quality, as usual - thanks for adding the updated Cct diagram with the good packing, and also for all the efforts to make these boards available, Many thanks - much appreciated.
James
Hi Peter,
thanks for the explanation.
With two parts I am still not sure what typ I should use.
I like to use IXYS-diodes in ps-board but I don't know where to get them and wich typ maches best.
There is the advice in the ZV9 manual to adjust the voltage on the J-fet with a powerpotentiometer (It was R3 I think). What type is suitable and where can I buy it? I just found very expensiv potis for 20w.
Has anbody experiences?
Greetings Adrian
thanks for the explanation.
With two parts I am still not sure what typ I should use.
I like to use IXYS-diodes in ps-board but I don't know where to get them and wich typ maches best.
There is the advice in the ZV9 manual to adjust the voltage on the J-fet with a powerpotentiometer (It was R3 I think). What type is suitable and where can I buy it? I just found very expensiv potis for 20w.
Has anbody experiences?
Greetings Adrian
I'm not familiar with IXYS, in my F3 amp I used those bridges: http://www.diyaudio.com/forums/attachment.php?s=&postid=326435&stamp=1076894979 (bought years ago through Forum).
As to the pot, use a regular trimpot (not a power unit); later you can put fixed resistor in its place.
BTW, the pics of my Zv9 using older boards, have been posted here: http://www.diyaudio.com/forums/showthread.php?postid=1254948#post1254948
As to the pot, use a regular trimpot (not a power unit); later you can put fixed resistor in its place.
BTW, the pics of my Zv9 using older boards, have been posted here: http://www.diyaudio.com/forums/showthread.php?postid=1254948#post1254948
The schematic shows R5 as being 2.7R. Would this be sufficient to get the 1.1V on the JFet, or is fine tuning this value a real neccessity ?
Peter Daniel said:
I have to correct my previous statement: I actually didn't use any pot here, but calculated the resistor value using info in Zv9 article: http://www.passdiy.com/pdf/ZV9.pdf
It was the other trimpot that I replaced with fixed resistor.
Boards still available?
To Peter:
Hi, I put my name in the Wiki for the group buy but have been so busy that I've lost track of things... I'm still interested in a set for a stereo F3, do I need 2 PSU boards or just one?
Will one PSU board be able to supply the two audio channels?
Will it be better to use one PSU board for each audio channel in a dual mono configuration?
Could you please let me know of the shipping costs to Portugal?
Thanks,
Luis
To Peter:
Hi, I put my name in the Wiki for the group buy but have been so busy that I've lost track of things... I'm still interested in a set for a stereo F3, do I need 2 PSU boards or just one?
Will one PSU board be able to supply the two audio channels?
Will it be better to use one PSU board for each audio channel in a dual mono configuration?
Could you please let me know of the shipping costs to Portugal?
Thanks,
Luis
I have at least 10 more amp boards available. For a stereo set you would need one PS board. For dual mono, PS board breaks in half (along scoring line). Depending on capacitors type, you may install up to 2 x 22,000uf per each side of PS board, which should work fine.
The PCB prices include international shipping (insurance is optional, at $7 extra).
The PCB prices include international shipping (insurance is optional, at $7 extra).
Hi peter,
Boards F3 and F4 are arrived on saturday
Everything is perfect
You've done a great job
Domo arigato
Thanks
😀 🙂
Boards F3 and F4 are arrived on saturday
Everything is perfect
You've done a great job
Domo arigato
Thanks
😀 🙂
Did I just fry my Jfet ?
Hey all.
Tonight I was planning to measure the Vds of my jfets, using the circuit described in the ZenV9 pdf.
I bought a desktop power supply capable of 1.5A, with selectable voltages from 3V to 12V (seemed suitable). I up the fet, turned on the power supply, and noticed it putting out 4.7V rather than 3V, and the jfet was getting VERY hot. I killed the power right away, but could I have fried the fet ?
Do these things need any heatsinking while measuring the Vds ?
Hey all.
Tonight I was planning to measure the Vds of my jfets, using the circuit described in the ZenV9 pdf.
I bought a desktop power supply capable of 1.5A, with selectable voltages from 3V to 12V (seemed suitable). I up the fet, turned on the power supply, and noticed it putting out 4.7V rather than 3V, and the jfet was getting VERY hot. I killed the power right away, but could I have fried the fet ?
Do these things need any heatsinking while measuring the Vds ?
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