No, an iPod can drive an F5 quite loudly
That's what I was afraid of.
Also, replacing R3 & 4 with a 3.3k resistor brought the bias voltage closer to .59, but not close enough. It gets up to about .50, then drifts downward. Still no DC at output. Might try 4.7k resistors just for fun.
Thanks,
V~
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Can I use the same test gig to test P-Channel jefets as showing in post #15?
Thanks,
Vince
Not exactly, got to flip things around.
Check this one out.
http://www.diamondstar.de/transistor_matching_jfet.html
Found the problem
The schematic Fig 6 shows Q3 as a IRFP9240 and Q4 as a IRFP240.
The article says, "The output MOSFETs are the IRF240 N channel type (Q3) and the IRD9240 P channel type (Q4).
I'm probably the only fool that followed the article instead of the schematic.
Can someone verify this for me?
I'm using IRFP140s and IRFP9140s.
Thanks,
Vince
The schematic Fig 6 shows Q3 as a IRFP9240 and Q4 as a IRFP240.
The article says, "The output MOSFETs are the IRF240 N channel type (Q3) and the IRD9240 P channel type (Q4).
I'm probably the only fool that followed the article instead of the schematic.
Can someone verify this for me?
I'm using IRFP140s and IRFP9140s.
Thanks,
Vince
Finally!
I think I have it working! Got .60 across R12 and .078 DC at the output.
Approximately the same on both channel.
For a second I thought I let out the smoke out of this build!! It was just the alligator clip rubber jacket that got too close to a 3w resistor!!
This build was done on Peter Daniel's F5 amp board.
Won't check this one off as done until I hear some music out of it.
Thanks everyone.
I think I have it working! Got .60 across R12 and .078 DC at the output.
Approximately the same on both channel.
For a second I thought I let out the smoke out of this build!! It was just the alligator clip rubber jacket that got too close to a 3w resistor!!
This build was done on Peter Daniel's F5 amp board.
Won't check this one off as done until I hear some music out of it.
Thanks everyone.
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Pics
I agree.
Some Pics...
http://i145.photobucket.com/albums/r216/vdinenna/Audio Projects/F5_1_Fin.jpg
http://i145.photobucket.com/albums/r216/vdinenna/Audio Projects/F5_2_Fin.jpg
http://i145.photobucket.com/albums/r216/vdinenna/Audio Projects/F5_4_Fin.jpg
you will find that the efforts you put in will be well worth it. Very fine amp indeed.
I agree.
Some Pics...
http://i145.photobucket.com/albums/r216/vdinenna/Audio Projects/F5_1_Fin.jpg
http://i145.photobucket.com/albums/r216/vdinenna/Audio Projects/F5_2_Fin.jpg
http://i145.photobucket.com/albums/r216/vdinenna/Audio Projects/F5_4_Fin.jpg
F5 Problems
Thanks Tea-Bag and Vdi-Nenna. I have been through two PD amp boards and not able to get past the very first testing step with a veriac. And the reason...there may be others, that's for sure...is I did exactly what vdi-Nenna did. Swapping the output transistors. Thanks
Jan
Thanks Tea-Bag and Vdi-Nenna. I have been through two PD amp boards and not able to get past the very first testing step with a veriac. And the reason...there may be others, that's for sure...is I did exactly what vdi-Nenna did. Swapping the output transistors. Thanks
Jan
I did exactly what vdi-Nenna did. Swapping the output transistors.
The first build is still a mystery. The build that worked was a different set of amp boards. Once I understood what was correct (schem or article) I saw that I had the FETs correctly installed.
Increasing the 2.2k resistors didn't help either.
I'm listening to the F5 and B1 right now. It's hard to describe. I can say nothing seems hidden. I've actually heard a few songs where before the lyrics were indistinguishable. Not anymore. It's like untying a musical knot.
V~
F5
Hi
I can't wait to get home to see if I can get this up and going. I got a hold of PD's gainclone kit after two tries on the F5. My hope to was to have the B1 and F5 drive my KJKing open baffles. With and Adom 555 2 and the B1, I am hearing somthing like what you are describing. I hope the F5 takes to that level. Thanks
Jan
Hi
I can't wait to get home to see if I can get this up and going. I got a hold of PD's gainclone kit after two tries on the F5. My hope to was to have the B1 and F5 drive my KJKing open baffles. With and Adom 555 2 and the B1, I am hearing somthing like what you are describing. I hope the F5 takes to that level. Thanks
Jan
Right now I am running F5 on top, F5 on bottom, with Open Baffles.
Lowther on top, 2 EM Alpha 15A's on bottom like mjk stuff.
I also put T-bass on the bottom end, and this brought down extension real well.
Sound is pretty pinpoint on the F5s even on the low end. Good times!
Lowther on top, 2 EM Alpha 15A's on bottom like mjk stuff.
I also put T-bass on the bottom end, and this brought down extension real well.
Sound is pretty pinpoint on the F5s even on the low end. Good times!
Lowther on top, 2 EM Alpha 15A's on bottom like mjk stuff.
I use the same 15 in woofers and only drem of Lowther. I have 6.5 inch Fostex 166esr for the high end. It is better than the 103's that MJK used first. Which lowther are you using? Like MJK?
Jan
I have DX4 lowthers with a notch filter on them. I have had them for some time. I have not heard the fostex speakers.
I hear the PM6A is not quite as detailed, but very magical and doesn't need as much or no filtering in OB.
There seems to be lots of options now for full range drivers. I am not the right person to ask.
I hear the PM6A is not quite as detailed, but very magical and doesn't need as much or no filtering in OB.
There seems to be lots of options now for full range drivers. I am not the right person to ask.
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