I did that with fan blowing on the mosfets, increaing resistance across 2 solder points of pots from 50 ohm to 200 ohm, but the voltage across R11 and R12 remain 0mv. Any idea?cviller said:Now try to crank up the resistance on P1 and P2 - this should give you some current through R11 and R12, but be careful... to my understanding you have no heat sink attached!
It almost doesn't matter how you orient Peter's boards for the F4 as the outputs are so gobbed together.
But for the F5 with only two MOSFETS, one on each side probably IS pretty optimal...
I'm thinking I could make one of my Burning Amp cases into a four channel F4 to use balanced for two channels, then convert my current F4 towers into the F5's with cultures' boards that would just bolt on.
Good marketing feature culture! And the board looks lovely to me, but I haven't traced it out. I'd order a pair if they were made available..
Variac said:
Hi Variac
Since ordering 10 sets is as expansive as 2 sets i think it should be possible to make a few sets available.... it might take a while before they are finished because this PCB designing thing is a new adventure to me. Still have to figure out if i didn't make stupid mistakes (non existing hole sizes or what ever) and where to order (looking at pcbcart.com at the moment) what specs the boards should have (thickness, surface finish...).
And one more thing, i'll be going on an other new adventure tomorrow.. riding waves in Morocco
never done that before btw, this is what the pcb looks like right now, moved most traces to the bottom and a few other minor changes
Attachments
labjr said:
I'm still open for doing a small GB of my layout (including a little cleanup).
http://www.diyaudio.com/forums/showthread.php?postid=1672336#post1672336
blessing. Maybe commercial F5 isn't sold out. So we need to wait - or Papa wants to publish boards still to monitor our greedy behavior.
Please place posts related to group buy here:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=134554
http://www.diyaudio.com/forums/showthread.php?s=&threadid=134554
labjr said:
Hi labjr,
My guess is that if six fets in an F4 on the same size board works fine this shouldn't be a problem either, i could be wrong though...
In post #2136 you can see a picture of the sinks i use and i think the fet placement isn't that bad this way. I also have a few heatsinks witch are more stretched out, i might use a few extension wires to place them further apart (if i decide to build an other F5).
cheers,
c.
speaker efficiency...is it critical?
Reading the Pass Labs forums has me jazzed!
Build on my B1 has been slow since the birth of my soon a few weeks ago, but I'm almost there.
I'm confused about the discussions regarding speaker efficiency and I'm not sure if the F5 will be adequate to drive my Spica TC-50s. They were rated at 84 dB/W/m at nominal 4 ohm impedance. This doesn't sound like a whole lotta efficiency.
The F5 sounds tantalizing to build, but will my Spicas sound pfffft with the F5 powering them?
Reading the Pass Labs forums has me jazzed!
Build on my B1 has been slow since the birth of my soon a few weeks ago, but I'm almost there.
I'm confused about the discussions regarding speaker efficiency and I'm not sure if the F5 will be adequate to drive my Spica TC-50s. They were rated at 84 dB/W/m at nominal 4 ohm impedance. This doesn't sound like a whole lotta efficiency.
The F5 sounds tantalizing to build, but will my Spicas sound pfffft with the F5 powering them?
Re: speaker efficiency...is it critical?
That's about the least efficient speaker I've ever seen. I almost bought a pair of them once. I would think you'd need more power.
However, some amplifiers sound surprisingly louder than their ratings would have you believe. I'm not sure if the F5 is one of them.
sonidos said:Reading the Pass Labs forums has me jazzed!
Build on my B1 has been slow since the birth of my soon a few weeks ago, but I'm almost there.
I'm confused about the discussions regarding speaker efficiency and I'm not sure if the F5 will be adequate to drive my Spica TC-50s. They were rated at 84 dB/W/m at nominal 4 ohm impedance. This doesn't sound like a whole lotta efficiency.
The F5 sounds tantalizing to build, but will my Spicas sound pfffft with the F5 powering them?
That's about the least efficient speaker I've ever seen. I almost bought a pair of them once. I would think you'd need more power.
However, some amplifiers sound surprisingly louder than their ratings would have you believe. I'm not sure if the F5 is one of them.
hi.. i have 2x20 volts 250watts(i think it is not very quality)ac transformer..is it possible to supply f5 with this transformer?.what is the max dc value of the amp?.i think i will put 1ohm 10watts resistor between bridge diode and transformer..what do you think about this?does it reduce the supply noise too?thanks