When I look at the price of Vacuum Tube's , JFETs look inexpensive . I am looking at a matched quad of LSK170 / LSJ74 at the Diystore for $39 . Yes compared to what they cost years ago they are expensive now. Thanks to Linear Systems and the Diy Store , we can build those wonderful Nelson Pass designs. It's a great time to be a DIYer.
I understand that but are there drop in equivalents like there is for the whammy for example you can use IRF610 and IRF9610 instead of the more expensive counterparts.
Why not redesign the circuit yourself, to use other components that you believe are cheap and plentiful? You may not get the Nelson Pass sound but you certainly will get the Gaz2613 sound, which I suspect will please you even moreso. And then you can write a big long article about it, maybe a 2-part or 3-part series, for your audiosy website. It would definitely be a win-win.
If I wanted a patronising answer I would have just asked for one. Don't assume we are all electrical engineers because we aren't. Some of us just like to build but are also aware that some components can be substituted in some cases.
I am obviously not going to find the answer I am looking for here so I'll find something else to build instead.
The simple answer is no, there is not a replacement for the K170/J74. There are some SMD N-channel jets that are sorta close, but nothing remotely similar for the P-channel.
That Linear Systems even makes their K170/J74 is a small miracle in and by itself. Although it may seem expensive, it's still a bit cheaper than the only known source of genuine Toshibas, "Punkydawgs" on eBay. https://ebay.us/VdQqju
The circuit is incredible, I'm sure you'll like it.
That Linear Systems even makes their K170/J74 is a small miracle in and by itself. Although it may seem expensive, it's still a bit cheaper than the only known source of genuine Toshibas, "Punkydawgs" on eBay. https://ebay.us/VdQqju
The circuit is incredible, I'm sure you'll like it.
you got your answer, but spoon-feed is so lucrative .......
there is also sticky thread - Replacement For Toshiba 2SK170/2SJ74
btw. don't assume that we all are electrical engineers because we aren't
I wasn't asking to be spoon fed just if there were drop in replacements like there is with the Whammy so I thought my question was valid.
Thank you for the link I'll have a good read through it.
A big thanks to Linear Systems and the diy store for making and selling a low demand part. Those JFET designs and parts do have a unique sound that I love. The ACP+ is truly a really good preamp/ headphone amp and is well worth the price of the FETs. I have spent more money on tweaks that did not work. There is always someone willing to take your money for some tweak. I think money is better spent on the amplifying device .
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There are a half dozen diyAudio members who offer their services doing PCB layout at reasonable hourly rates. Among them: Prasi, jhofland, JPS64 and several others whose names I don't seem to recall at the moment. Why not pay them to lay out a board right now rather than waiting? Then you get your ACP+ immediately, and you also have the option, but not the obligation!, to donate those Gerber CAD files to all other diyAudio members, so everybody can get their own ACP+ boards fabbed too. You also have the option to organize a committee of like-minded people, who all agree to split the PCB layout cost. Then the expense to you falls by a factor of N. The greater the committee size (N), the less the expense.
Somewhat different from the original design in terms of layout (and I don't normally advertise my own design), but I've posted one here a while ago
Project files: The ACP+ clone… | theslowdiyer
Project files: The ACP+ clone… | theslowdiyer
For a quick test, I downloaded the Gerber CAD files from Nisbeth's web page. They appear to be correct. My free, in-browser Gerber Viewer software ( at www.pcbxprt.com ) reads them without trouble. See 2nd attached image below.
I visited PCBShopper – A Price Comparison Site for Printed Circuit Boards to get price quotes, including shipping to Sweden. Price for ten copies of the PCB, delivered to Sweden, ranged from 100 SEK to 350 SEK depending on which fab and which shipping option (speed) you select. Remember, each PCB is one (mono) channel. You need two PCBs to make a stereo headphone amp / preamp.
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I visited PCBShopper – A Price Comparison Site for Printed Circuit Boards to get price quotes, including shipping to Sweden. Price for ten copies of the PCB, delivered to Sweden, ranged from 100 SEK to 350 SEK depending on which fab and which shipping option (speed) you select. Remember, each PCB is one (mono) channel. You need two PCBs to make a stereo headphone amp / preamp.
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Attachments
Sov, I should have a couple of spare sets. I need to dig them out first, but send me a PM if you are interested and we'll take it from there.
Mark: Thanks. Gerbers are generated from Eagle with the SeeedStudio CAM-job which is also where I mostly get my prototypes made, but yes they should be readable without issues by any other manufacturer.
Mark: Thanks. Gerbers are generated from Eagle with the SeeedStudio CAM-job which is also where I mostly get my prototypes made, but yes they should be readable without issues by any other manufacturer.