yippee!
Ok, I swapped out the 2 jfets - one I noticed was a GR grade. Anyways, I put in two BL grade jfets and was able to set the bias within ten to twelve turns of the trimmers.
I let it cook for about an hour, adjusting the trimmers at the 1/2hr mark. My numbers for the right side of my amp are .593v & .594v offset was +/- 0v.
I'll double check my left side, haven't seen those numbers in a while and let that cook too.
I'll be moving it into my audio rack today.
Ok, I swapped out the 2 jfets - one I noticed was a GR grade. Anyways, I put in two BL grade jfets and was able to set the bias within ten to twelve turns of the trimmers.
I let it cook for about an hour, adjusting the trimmers at the 1/2hr mark. My numbers for the right side of my amp are .593v & .594v offset was +/- 0v.
I'll double check my left side, haven't seen those numbers in a while and let that cook too.
I'll be moving it into my audio rack today.
muffled speaker?
Hmm, I racked my F5 and plugged it in to give it a listen to. The results are good with my optimus (Radioshack) speakers. The Wharfedale Diamond speakers (they were the rear channel pair in my HT) I hooked up were not so great. One speaker gave me a muffled sound, there a dent in the tweeter cones - other than that I'm not sure what up with them?
I'll be shopping for a new pair of speakers - I'm not sure if I can repair these speakers.
Any speaker suggestions out there?
F5 amp
B1 buffer / dcb1 -lightspeed
Hmm, I racked my F5 and plugged it in to give it a listen to. The results are good with my optimus (Radioshack) speakers. The Wharfedale Diamond speakers (they were the rear channel pair in my HT) I hooked up were not so great. One speaker gave me a muffled sound, there a dent in the tweeter cones - other than that I'm not sure what up with them?
I'll be shopping for a new pair of speakers - I'm not sure if I can repair these speakers.
Any speaker suggestions out there?
F5 amp
B1 buffer / dcb1 -lightspeed
Buy what makes you happy. Audition as many as you can, there must be some places in Toronto where you can buy/audition speakers.
I personally like the various Canadian brands, Paradigm, PSB, Energy, etc...
Conversely, there are neat kit options out there, from Madisound, Parts Express, and such.
I personally like the various Canadian brands, Paradigm, PSB, Energy, etc...
Conversely, there are neat kit options out there, from Madisound, Parts Express, and such.
yes , for us working mortals , the speakers are the weak point . good speakers cost $ even for diy'ers .
that said i was very disappointed with my F5 ( sorry guys ) , but i spent a ton of money and time and found it "lacking" to say the least .
my Peter Daniels gainclone blows my f5 out of the water .
my speakers are psb , b&w , braun and mark audio depending on the moment . my preamps are nad and yamaha . my other amps are b&o 4000 , phase linear 400 , yamaha & marantz av .
thing is merlin , some love the F5 , some don't . me i'm not going to love something , just because someone tells me that i should .
cheers Woody
that said i was very disappointed with my F5 ( sorry guys ) , but i spent a ton of money and time and found it "lacking" to say the least .
my Peter Daniels gainclone blows my f5 out of the water .
my speakers are psb , b&w , braun and mark audio depending on the moment . my preamps are nad and yamaha . my other amps are b&o 4000 , phase linear 400 , yamaha & marantz av .
thing is merlin , some love the F5 , some don't . me i'm not going to love something , just because someone tells me that i should .
cheers Woody
and in reply to speakers you might want to think about these if you have the room .
http://www.diyaudio.com/forums/multi-way/97043-elsinore-project-thread.html
http://www.diyaudio.com/forums/multi-way/97043-elsinore-project-thread.html
While everyone is entitled to an opinion, I would suggest something is very wrong with your F-5....?
Russellc
Could very well be since most F5 users think the amp is a step up above what else they've owned, me included.
That said, I haven't tried the F5 on anything other than efiicient speakers. I was seeing 2w. output to Altec drivers at high db levels.
Didn't bother to check the draw on the Fostex BLH's because, who cares? I thought the F5 really made some magic with the BLH's (actually turned up flaws), the sound was so crystal in the midrange but with no glare, just sweet and even delicate on some passages.
As to the OP's speaker needs, I'd aim for a speaker system that is efficient and can keep up to the quality of the F5. To me, this is best accomplished by DIY. There are a lot of vintage and new woofers that, combined with a CD/horn, planar, or ribbon could meet the challenge. Domes not excluded.
You might want to seal it with something more forgiving, more resiliant (like the original rubber seal), and less permanent (in case you need to tinker more). I'd recommend an RTV clear silicone--lots of choices in your local hardware store, solid as clear silicone caulk in a tube.
Duct tape, solder wick, and RTV silicone--you can never have enough, of any of these.....!
Hi
After reading all this , I just want to ask before I place order for heatsink is that if I build F5 using Conrad Heatsink MF35-75 is that enough or too hot , I will try to spread two power FET as far apart as possible ( aprox 130 -160 mm apart ) to help about the heat , thanks everyone in this thread , very helpfull .
Edit : because space limited so I have to go slim .
Regards
After reading all this , I just want to ask before I place order for heatsink is that if I build F5 using Conrad Heatsink MF35-75 is that enough or too hot , I will try to spread two power FET as far apart as possible ( aprox 130 -160 mm apart ) to help about the heat , thanks everyone in this thread , very helpfull .
Edit : because space limited so I have to go slim .
Regards
Whole bunch of factors to consider--ambient temp, ambient airflow, heatsink orientation (vertical/horizontal), heatsink exposure to the airflow, MOSFET bias voltage/current (and therefore heat generation).
The most dominant question--how does the heat dissipation specification for the MF35-75 compare to the requirements specified in the F5 manual (available on-line, at the First Watt website).....?
The Peter Daniel boards are cunningly and conveniently available from Peter himself.
Audisector.com (although you will find no information or mention on the PCBs on that website...)
so it's better to contact him directly via email -- phdaniel@sympatico.ca
He is a great guy to deal with and his product is very nice indeed!
Audisector.com (although you will find no information or mention on the PCBs on that website...)
so it's better to contact him directly via email -- phdaniel@sympatico.ca
He is a great guy to deal with and his product is very nice indeed!
The Peter Daniel boards are cunningly and conveniently available from Peter himself.
Audisector.com (although you will find no information or mention on the PCBs on that website...)
so it's better to contact him directly via email -- phdaniel@sympatico.ca
He is a great guy to deal with and his product is very nice indeed!
Search in the group buy forum, the thread is much smaller than the gigantic F-5 thread, and is specific to the Daniels boards.
Russellc
I have a silicon chip 20W class A amp running at +/-22V and 1.1 amps using the 30-75 heat sink it runs at 52 degrees celcius (natural convection) in a room at around 24 degrees C. So if you want it to be touchable I would strongly suggets the heat sink you refer to is just a bit to small. I am currently building an F5 and I have decided to use much bigger geat sinks to keep the temperature down, I hope to get it to about 35 degrees but the heat sinks I have each weigh 5 Kgs.