Zchopper - basically, there isn’t any alternative that would work for that.
Be careful and dutiful, double check your work, and relax a little because the Jfets are pretty durable at these voltages. Lots of people build these amps, few kill the Jfets. 😀
Be careful and dutiful, double check your work, and relax a little because the Jfets are pretty durable at these voltages. Lots of people build these amps, few kill the Jfets. 😀
What do I want
A month or so ago I dove into my first DIY project. Turns out to be an F6 with a BA-3 pre amp. Working my way along and then I asked myself what do I want to get out of this besides a great learning experience and something that sounds great. So. I thought I would thow it out to the crowd. Like everyone else I want it musical, warm, accurate, detailed and no noise. but, it has to be great at producing Led Zeppelin. This is going to get judged on how Zepp sounds and to be specific "When The Levee Breaks" has to be off the charts good. I don't care if I am headed in the wrong direction it's where I end up that counts. Pleas let me know what you think. Thanks,
Don
A month or so ago I dove into my first DIY project. Turns out to be an F6 with a BA-3 pre amp. Working my way along and then I asked myself what do I want to get out of this besides a great learning experience and something that sounds great. So. I thought I would thow it out to the crowd. Like everyone else I want it musical, warm, accurate, detailed and no noise. but, it has to be great at producing Led Zeppelin. This is going to get judged on how Zepp sounds and to be specific "When The Levee Breaks" has to be off the charts good. I don't care if I am headed in the wrong direction it's where I end up that counts. Pleas let me know what you think. Thanks,
Don
@ Donhughes111
Congrats on your preamp and amp builds. Two very nice pieces of gear.
Music recordings are a funny thing. A recording might sound one way on one system; it will sound different on another audio system. Nailing a system that reproduces Led Zepp perfectly for you on first try is a tall order. Some days your system might not sound like it did the day before and you will have no idea why. Might be you or it might be the system.
What happens if your builds don't reproduce When the Levee Breaks as you'd hoped? Here's what I think you should do. Go through your entire library of music and look for music that does sound good to you or "off the charts".
You will be surprised at what does and doesn't sound good.
You might also find music that you thought was the bomb turns out to be just OK and music genres or recordings you didn't give a second chance before turn out to be stunning.
It's a journey, not a gimme when building good gear. Be the Seeker! 🙂
Just my two cents!
Good luck!
Vince
Congrats on your preamp and amp builds. Two very nice pieces of gear.
Music recordings are a funny thing. A recording might sound one way on one system; it will sound different on another audio system. Nailing a system that reproduces Led Zepp perfectly for you on first try is a tall order. Some days your system might not sound like it did the day before and you will have no idea why. Might be you or it might be the system.
What happens if your builds don't reproduce When the Levee Breaks as you'd hoped? Here's what I think you should do. Go through your entire library of music and look for music that does sound good to you or "off the charts".
You will be surprised at what does and doesn't sound good.
You might also find music that you thought was the bomb turns out to be just OK and music genres or recordings you didn't give a second chance before turn out to be stunning.
It's a journey, not a gimme when building good gear. Be the Seeker! 🙂
Just my two cents!
Good luck!
Vince
Seeker could be damn lucky bztrd from first (base? 
) if clever enough to mate that amplification with huge enough and sensitive enough speakers
beware , sensitive and efficient can be the same , but more often it isn't
both Altec 511 and modern JBL are efficient 15" drivers , but 511 is way more sensitive than other one...
) if clever enough to mate that amplification with huge enough and sensitive enough speakers beware , sensitive and efficient can be the same , but more often it isn't
both Altec 511 and modern JBL are efficient 15" drivers , but 511 is way more sensitive than other one...
I know about back loaded.
Fostex BK-20 Folded Horn Kit - Pair
I'm talking about horns.
Avantgarde Acoustic Uno Series Two loudspeaker | Stereophile.com
Oswalds Mill Audio - Imperia | OMA Loudspeakers
Amazing soeakers | Audio room, Audiophile speakers, Hifi audio
I would rather a pair of these...
A25 Loudspeaker
https://www.madisoundspeakerstore.c...6-10-2-way-kit-pair-based-on-the-classic-a25/
Fostex BK-20 Folded Horn Kit - Pair
I'm talking about horns.
Avantgarde Acoustic Uno Series Two loudspeaker | Stereophile.com
Oswalds Mill Audio - Imperia | OMA Loudspeakers
Amazing soeakers | Audio room, Audiophile speakers, Hifi audio
I would rather a pair of these...
A25 Loudspeaker
https://www.madisoundspeakerstore.c...6-10-2-way-kit-pair-based-on-the-classic-a25/
A really detailed question. The heatsinks I am using (and the ones from the BOM) are a fairly tight fit to the MOSFETS so two questions.
1. if the heatsink is not touching anything other than the MOSFET does it make a difference?
2. I have been trimming the keratherm tight to the MOSFET. Should I leave it "long" on the edges and let it wrap around the MOSFET to insure they don't touch.
Lots of ways to go wrong with the details when you're trying to get electrons to do what you want.
Don
1) As you suspect, the heatsink should touch nothing but the Mosfet.
2) You don't need an insulator. Since the heatsink touches nothing, there is no need to insulate it. A little heatsink goop would be somewhat helpful, but not necessary. Save the Keratherm for the output MOSFETs on a power amp.
2) You don't need an insulator. Since the heatsink touches nothing, there is no need to insulate it. A little heatsink goop would be somewhat helpful, but not necessary. Save the Keratherm for the output MOSFETs on a power amp.
Conventional wisdom is "no, it won't make a difference".
But I don't like the practice anyway. I'd say "it won't make a difference until you stick a screwdriver/wirecutters/whatever into the case and bump it...."
Cheers,
Jeff.
One other note: when the heatsinks are left floating it's common practice to not have any ground-plane under the heatsink on the board. That way you're not relying on the solder mask for insulation....