Not sure I completely understand.
There is still another plate that sits beneath mesh.
Purple wire is electrostatic screen.
Please tell me your concern
first - that hole is not burred good enough for that task (I had few of them in hands)
second - even if that wire is just for e-static shield , never put sole wire through any metal plate hole - always put natural wire pairs (rail and return)
I know nothing will happen in this exact case , but that's just decent engineering praxis
route that wire to the front , then down
https://youtu.be/kFZTko2TXNY
second - even if that wire is just for e-static shield , never put sole wire through any metal plate hole - always put natural wire pairs (rail and return)
I know nothing will happen in this exact case , but that's just decent engineering praxis
route that wire to the front , then down
https://youtu.be/kFZTko2TXNY
Ok. Just want to understand your thinking.
What if I use a braided aluminium/copper sheath around cable to protect insulation from damage?
What if I use a braided aluminium/copper sheath around cable to protect insulation from damage?
Would that reduce the gain by a factor of 2? Reason I ask is my F6 is a little dark sounding also, it has IRFP240 and .47 and .57 resistors. This sound is compared to my Aleph J. Although the F6 has deeper and more pronounced bass for sure, the mids and highs don't seem as clear and bright as the Aleph.
Gain goes from about 5V/V (stock) to about 3V/V.
It's definitely worth trying, it's an opportunity to gain some insight in various effects.
Edit: Alternatively you could keep feedback resistor network same and change IRFP240 with Higher Transconductance (maybe 4S) SiC devices
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Well, I have read a few reviews of the F6 and there is no mention of dark or dull. I am presuming these are Nelson's production IRFP240 versions. I wonder what Nelson has done differently if anything? One thing with mine I just thought of, I didn't use the Silmic caps I used Nichicon type KA. They are said by them to be high quality "audio" type with prodigious bass capability. I can attest to the bass statement. Could these caps play that much of a role in shaping the F6's sound?
hi oreo, don´t know about how the cap is involved soundwise, but my F6 seems to developed to a little more bright/right side for me. Wait at least two days. Maybe it´s my woodoo thinking and because of tweaking the speakers a little i lost reference somehow.
for the resistors, i changed the feedback (a second 100 ohm to make it 50 ohm) what made it a bit more foreward but also a little more tight, less lush. i went back to the original.
For the source R´s, i changed R2 from .56 to .47 and one could say it was clearer, but for me the soundstage, depth, was more flattend. So i went back to original too.
i like it better now 🙂
st.
for the resistors, i changed the feedback (a second 100 ohm to make it 50 ohm) what made it a bit more foreward but also a little more tight, less lush. i went back to the original.
For the source R´s, i changed R2 from .56 to .47 and one could say it was clearer, but for me the soundstage, depth, was more flattend. So i went back to original too.
i like it better now 🙂
st.
Thanks for the reply. One thing I should mention is my bias is 1.3 A. I think Nelson's was 1.5. I do have a bit of room to bump mine up to that level so I may try that and report back.
Biasing up for first time on lab power supply.
Easily achieved less than 1mV dc offset.
Just letting it get up to temperature before making final tweaks to bias.
Used 5.6V Zeners instead of original 5.1V Zener with 7.5k instead of 10k. Works beautifully.
(Note to self: counter clockwise to bias up (memory like a sieve)) Hahahaha
Easily achieved less than 1mV dc offset.
Just letting it get up to temperature before making final tweaks to bias.
Used 5.6V Zeners instead of original 5.1V Zener with 7.5k instead of 10k. Works beautifully.
(Note to self: counter clockwise to bias up (memory like a sieve)) Hahahaha
Well it doesn't get hot at 1.3A with 5U heat sinks so its not a concern in that regard.
I hope at some point they revise the pcb though, it's sought of messing with my head, these sought of things irritate me. Hahahahahaha
I wouldn't let it stop you from building it. It won't affect the performance of the amp.
I don't understand why they haven't produced a revised pcb though, F6 has been out for a long time. Very easy to fix this.
More to the point, does that lab supply really need a cushion for a hat? Maybe it's running too cool? 🙂
(I know you probably just wanted to shade the meters for a better photo)
(I know you probably just wanted to shade the meters for a better photo)
