Hello community, this is my first post how can you see 
I'am planning to build an First Watt F6 amplifer.
First thing that i want that you need to understand, that i beleive in that amplifier.
I mean i personally beleive in that fact, that this amplifer can deliver me performance for their money that i can't get for buying any amplifer that offers a market and big companies like (Onkyo, Cambridge Audio e.t.c).
I'am already buy heavier parts like transformer that is (Antek 400VA + Shield) and Amplifer case from eBay.
It's time to buy smaller parts like PCB, capacitors, wiring, connectors, resistors e.t.c
So i have many questions, if you know an answer, please answer to them, thanks!
1) Buying transistors from diyaudiostore with Grade A for F6 amplifer is waste of money or Grade B is good enough?
2) Which capacitors in power supply originally use Nelson Pass in his F6 amplifer, as i can see on pictures it's Panasonic 15000uF x 25v, but i'am can't find them on online stores, can someone give me link to them?
3) As F6 is power amplifer do i need an pre-amplifer for this power amplifer, or i can use first time my sound card, and then next buy a good DAC?
4) As i can see on picture amplifer do not have speaker protection, so i need this or not!? Just because i worry that in one moment broken transistors can burn my precious speakers.
I'am planning to build an First Watt F6 amplifer.
First thing that i want that you need to understand, that i beleive in that amplifier.
I mean i personally beleive in that fact, that this amplifer can deliver me performance for their money that i can't get for buying any amplifer that offers a market and big companies like (Onkyo, Cambridge Audio e.t.c).
I'am already buy heavier parts like transformer that is (Antek 400VA + Shield) and Amplifer case from eBay.
It's time to buy smaller parts like PCB, capacitors, wiring, connectors, resistors e.t.c
So i have many questions, if you know an answer, please answer to them, thanks!
1) Buying transistors from diyaudiostore with Grade A for F6 amplifer is waste of money or Grade B is good enough?
2) Which capacitors in power supply originally use Nelson Pass in his F6 amplifer, as i can see on pictures it's Panasonic 15000uF x 25v, but i'am can't find them on online stores, can someone give me link to them?
3) As F6 is power amplifer do i need an pre-amplifer for this power amplifer, or i can use first time my sound card, and then next buy a good DAC?
4) As i can see on picture amplifer do not have speaker protection, so i need this or not!? Just because i worry that in one moment broken transistors can burn my precious speakers.
1) Save some bucks, B grade will do.
2) Any brand you can buy from your electronic store close to you will do as long as voltage rating is higher than your rail. It is expensive to order them online as they are bulky/heavy stuff.
3) No need for pre-amplifier as this amp has gain as long as you can get 1-3V input, PC sound card would do. Think about DAC later once you finish amp.
4) Build amp first, listen and speaker protection later. Just don't short outputs means you should know what you're doing.
2) Any brand you can buy from your electronic store close to you will do as long as voltage rating is higher than your rail. It is expensive to order them online as they are bulky/heavy stuff.
3) No need for pre-amplifier as this amp has gain as long as you can get 1-3V input, PC sound card would do. Think about DAC later once you finish amp.
4) Build amp first, listen and speaker protection later. Just don't short outputs means you should know what you're doing.
Thanks for answers.
Few another questions.
1) Any chance to get original PCB or orginal PCB clone that estimate close to 1:1 to original PCB?
I ask because 99% matched amplifer case that i buy recently, already on the way to me. And i want to place blue LED's on front panel (of course blue LED's, since it's a pass amplifer
). Of course i can use glue or something like that, but i think that's dirty...
2) PCB that offer diyaudiostore can be mounted on original amplifer chasis? I mean distance between two output transistor mounting holes are silimar or not? Anyone know?
Few another questions.
1) Any chance to get original PCB or orginal PCB clone that estimate close to 1:1 to original PCB?
I ask because 99% matched amplifer case that i buy recently, already on the way to me. And i want to place blue LED's on front panel (of course blue LED's, since it's a pass amplifer
). Of course i can use glue or something like that, but i think that's dirty...2) PCB that offer diyaudiostore can be mounted on original amplifer chasis? I mean distance between two output transistor mounting holes are silimar or not? Anyone know?
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The case you have looks like one of the Chinese clones that are selling on Ebay. The only boards that I would use would be our Store boards that are proven and work great. You will probably have to drill and tap a few holes. No big deal actually, just another part of the diy journey. Members here will offer any assistance needed with the drilling and tapping of holes.
For the Jfets, you want matched pairs, so this is the one to get:
Linear Systems Matched JFET pairs (Grade B) – diyAudio Store (BETA)
The Panasonics have been discontinued so just anything of the appropriate voltage
and capacitance. If you are using a power supply PCB, make sure the caps aren't
too big for it.
Dennis
Linear Systems Matched JFET pairs (Grade B) – diyAudio Store (BETA)
The Panasonics have been discontinued so just anything of the appropriate voltage
and capacitance. If you are using a power supply PCB, make sure the caps aren't
too big for it.
Dennis
You bought a fake first watt case on eBay, maybe you should ask the seller for boards too. The store boards have Nelson's blessing and those on eBay probably don't...
Gluing LEDs are perfectly OK in my humble opinion. If that is out of the question, you could make an angled bracket from a piece of metal and fix it to the bottom plate with screws. I think I saw two holes [maybe] suitable for that.
This should be able to fix the LED with a suitable pressure towards the front plate cavity. Ahh, and you can get small plastic holders for the LED I believe, so it stays in place.
The wires plus and minus from the PCB to the LED you solder to the legs of the LED and cover the bare metal with heat shrink tubes. One red and one black as a proposal.
This should be able to fix the LED with a suitable pressure towards the front plate cavity. Ahh, and you can get small plastic holders for the LED I believe, so it stays in place.
The wires plus and minus from the PCB to the LED you solder to the legs of the LED and cover the bare metal with heat shrink tubes. One red and one black as a proposal.
R-K Rønningstad
Thanks very much for helping, i have same ideas in my mind about heat glue or LED holder in my mind before reading your posts. Just a nice that people at these forums help each other, thank you.
And probably final two questions.
1) Before placing order at DiyAudioStore.
Transistors with grade A give me increase in something (not to mention their cost), i mean a little addition to sound quality and smaller noise at output?
2) To set up amplifer BIAS and OFFSET i need a multimeter, multimeter that i have currently probably cost 20 bucks, that be enough or i need high resolution multimeter?
Thanks very much for helping, i have same ideas in my mind about heat glue or LED holder in my mind before reading your posts. Just a nice that people at these forums help each other, thank you.
And probably final two questions.
1) Before placing order at DiyAudioStore.
Transistors with grade A give me increase in something (not to mention their cost), i mean a little addition to sound quality and smaller noise at output?
2) To set up amplifer BIAS and OFFSET i need a multimeter, multimeter that i have currently probably cost 20 bucks, that be enough or i need high resolution multimeter?
It makes life simpler to have two digital meters, one for bias and one for offset.
You can pick them up quite cheaply.
You should also use a bulb tester when first switching on.
My adjustment pots worked in reverse, so were set high. The bulb tester allowed me to spot and correct this without the magic smoke escaping.
You can pick them up quite cheaply.
You should also use a bulb tester when first switching on.
My adjustment pots worked in reverse, so were set high. The bulb tester allowed me to spot and correct this without the magic smoke escaping.
That's great, still I would encourage every builder to invest in a variac. The best 100 bucks I ever spent!
I suppose if you were going to build one and be done it wouldn't be an investment, but who can build just one?
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