@shark70
like AndrewT said, this particular one MUST be low pinch off voltage type
2SK170 or LSK170 or 2SK117 or 2SK370 will be OK there.
Bad news: mpsh81 is out of order / out of stock with both Digi-key and Farnell (3 left in the US). This thread is to be blamed for that. Where can you get them? Substitutes?
Good news: The Vishay MKP 416 series of 1.1uF/63VDC is back on stock from Digi-key. These caps, specified for high frequency and high stability use, are some of the most transparent caps I found. It costs $1.61 for one. I ordered 100 pieces this morning for $0.91 each. I put some into my power amps to bypass the signal level electrolytic caps (before and at the VA stage, replacing the existing 0.01uF) and they sounded a lot better. I also put them in parallel to the DC feedback cap (each power amp must have one, unless you match all signal devices), did not expect anything but again it sounded a whole lot better. For 5k, 4 x 1.1uF mounted vertically in a string as output cap for one rail (|| 27uF electrolytic), 1 x 1.1uF for the Vref(|| 100uF electrolytic), so for a +/-15V reg, 10 x 1.1uF are required. I use these same caps for Salas v1.2 too. This is giving me the best sound. I also put them into my CD player output to replace the existing electrolytic caps. There are only 615 left at Digikey. If you want them, you have to be quick.
Good news: The Vishay MKP 416 series of 1.1uF/63VDC is back on stock from Digi-key. These caps, specified for high frequency and high stability use, are some of the most transparent caps I found. It costs $1.61 for one. I ordered 100 pieces this morning for $0.91 each. I put some into my power amps to bypass the signal level electrolytic caps (before and at the VA stage, replacing the existing 0.01uF) and they sounded a lot better. I also put them in parallel to the DC feedback cap (each power amp must have one, unless you match all signal devices), did not expect anything but again it sounded a whole lot better. For 5k, 4 x 1.1uF mounted vertically in a string as output cap for one rail (|| 27uF electrolytic), 1 x 1.1uF for the Vref(|| 100uF electrolytic), so for a +/-15V reg, 10 x 1.1uF are required. I use these same caps for Salas v1.2 too. This is giving me the best sound. I also put them into my CD player output to replace the existing electrolytic caps. There are only 615 left at Digikey. If you want them, you have to be quick.
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You must be kidding. Besides you and stormsonic and probably another couple of guys, who else built this regulator?
Anyway, mouser got lots left.
Good tip! You were able to tell the difference between these caps and other polypropylene caps?
I would pay Mouser $2 for the mpsh81 but $30 for shipment to Sydney.
The Vishay's are the only stack film high frequency capacitors I use. However, I did compare them to ICW SA Clarity caps (for Xover), which is highly recommended in Tony's site, and which compares very favourably to the Solen polypropylene caps (my own tests). The Vishay's are a lot better than the ICW SA. I concluded that stack film caps made for PCB especially for high frequency use are much better than those high voltage wound capacitors for Xover use. I also compared them to 1.0uF 240V polystyrene and they sounded possibly at the same level. They compare much favourably to Polyester MKT.
I would go as far as saying, don't bother to build these low impedance regulators unless you get capacitors like these. Even with MKT it is a waste of time. But there is no need to believe in snake oil and paying $$$$$ for those wound capacitors for Xover, a 1uF would cost you $10.
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If you want them cheap send me you address via email and I'll send you some mpsh81, how many do you need? mouser has a smaller shipping charge if you go to checkout and shipping options. By default it shows me $20, but then I can choose at checkout the $8 option. The price mouser shows me is $0.147
My line level XO/EQ circuits require 3 regulators. So 12 are needed.
Back in my mind, I was going to redo my NaO (by famous John K) active circuits, another pair of open baffle speakers I own (with the aim of selling them for a few thousand dollars because I am out of work now) so 1-2 more regulators are needed. 8 more.
Then I must also need a buffer/preamp for doing loudspeaker measurements, 1 more regulator is needed.
So a total of 24 mpsh81 are needed.
For now, I could possibly unsolder the ones from my previous 2c and 5d boards, just enough to get my current project finished. But if I overheat them while removing them (how nice if they have only one leg for removal!) then bad luck. I probably won't have time to do the NaO and other stuff now, but will leave them to the future.
If I run out of options, I will email you for two dozens. When I placed the order from Digikey this morning, the order value of $135 justified $30 shipment. But for a $3 order, I just don't wish to pay $30 for shipment. The e-bay guys can manage to charge $3-5 for shipping to Australia, top quality packaging too. The trouble is that there is no easy way for me to pay you. A postal money order costs $10 here, so I may better directly order from Mouser. I don't think you should fund a diyer's project if you are a designer.
Back in my mind, I was going to redo my NaO (by famous John K) active circuits, another pair of open baffle speakers I own (with the aim of selling them for a few thousand dollars because I am out of work now) so 1-2 more regulators are needed. 8 more.
Then I must also need a buffer/preamp for doing loudspeaker measurements, 1 more regulator is needed.
So a total of 24 mpsh81 are needed.
For now, I could possibly unsolder the ones from my previous 2c and 5d boards, just enough to get my current project finished. But if I overheat them while removing them (how nice if they have only one leg for removal!) then bad luck. I probably won't have time to do the NaO and other stuff now, but will leave them to the future.
If I run out of options, I will email you for two dozens. When I placed the order from Digikey this morning, the order value of $135 justified $30 shipment. But for a $3 order, I just don't wish to pay $30 for shipment. The e-bay guys can manage to charge $3-5 for shipping to Australia, top quality packaging too. The trouble is that there is no easy way for me to pay you. A postal money order costs $10 here, so I may better directly order from Mouser. I don't think you should fund a diyer's project if you are a designer.
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I was going to offer you the parts at the price I get them from mouser and the price of actual shipping, which would be much lower than what you quoted.
On the subject of funding other people's projects; yeah, I don't run a charity but I do help people when possible and have sent parts to some people free of charge in the past. When I can, I help people in need. No strings attached.
On the subject of funding other people's projects; yeah, I don't run a charity but I do help people when possible and have sent parts to some people free of charge in the past. When I can, I help people in need. No strings attached.
You may be right, or may be wrong.
I am sure that there are people who are very keen reading these threads, just don't directly participate in the talks. We don't know the number. There may even be a lot of people building your regulators!
So guys like you freely giving away your time, knowledge and valuable products (designs) to other people are really the guys I admire. You are servicing mankind and bringing a lot of happiness to people. It is better to be a giver than a receiver.
You don't believe in what I say? I posted the news that the Vishay Bluebox 1.1uF / 63VDC is now again available at Digikey at noon. Now a few hours later when I go back to the Digikey site, the stock items have reduced from 615 to 515. It is going fast. I watched that space from time to time since last year, usually they sell much slower than today. It could be somebody who has not read this thread bought them though.
You can't be serious! Here's a test. 
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