OK, I see you did reverse them. Try powering the Preamp with two 9V batteries in series to get 18V.
EDIT: " 2SK117GR via Aliexpress" - may be issue, I have a pile of fake 2SK117 / 2SK170 from ebay...there is one guy on the bay that does sell legit 2SK170...but before replacing them, try the battery...
EDIT: " 2SK117GR via Aliexpress" - may be issue, I have a pile of fake 2SK117 / 2SK170 from ebay...there is one guy on the bay that does sell legit 2SK170...but before replacing them, try the battery...
I only get my 2SK170 / 2SJ74 from ebay - he is legit.
https://www.ebay.com/itm/254361776756?hash=item3b3924b274:g:ynEAAOSwQeha7eV6
But you DO NOT need matched (but does not hurt) - send him an email asking for four unmatched and he should be able to give you a better price...
https://www.ebay.com/itm/254361776756?hash=item3b3924b274:g:ynEAAOSwQeha7eV6
But you DO NOT need matched (but does not hurt) - send him an email asking for four unmatched and he should be able to give you a better price...
Switched to series 9v… and success! Mostly! Is there supposed to be this much background noise? Took another video. Starts off with me muting the strings, then letting go and obviously the buzz/hum gets worse.
https://streamable.com/munin0
I may order some trusted FETs from ebay to swap and see if the buzz improves.
https://streamable.com/munin0
I may order some trusted FETs from ebay to swap and see if the buzz improves.
The pre has a lot of gain too.
You can take a resistor at the pre input across the Signal to ground (right at the jack). Start out with 470k and raise closer to 47k and it should quiet down and lose a little gain - pick one that sounds best...
Also, see original schematic. With Hi input has 33k in series, but with low input, 33k in series with 68k to ground for voltage divider to drop signal level. You may want to play with a resistor to ground there. I just put a resistor to ground right at jack and worked fine.
Also, my fake 2SK-117 worked, but did not sound as good with real 2SK-117 / 2SK-170
You can take a resistor at the pre input across the Signal to ground (right at the jack). Start out with 470k and raise closer to 47k and it should quiet down and lose a little gain - pick one that sounds best...
Also, see original schematic. With Hi input has 33k in series, but with low input, 33k in series with 68k to ground for voltage divider to drop signal level. You may want to play with a resistor to ground there. I just put a resistor to ground right at jack and worked fine.
Also, my fake 2SK-117 worked, but did not sound as good with real 2SK-117 / 2SK-170
Attachments
Perfect! If it sounds great, I would just keep the JFETs you have installed...its all about what sounds best...
I actually compared the 2SK-117 to the 2SK-170 and definitely prefer the 2SK-170 JFET better...2SK-117 sounded noisier and not as dynamic...I guess these could be better - fake 2SK-117 too...
hi! are there any pcbs left? I´d like to buy one, also, where did you guys get the dale rn55 resistors? I found a seller on ebay, but just sells some of the values required, not all of them, is there any hearable difference if I use regular film resistors? thanks!
All parts were purchased from Digikey in states. You should be ok going to a different type - stay within values tho...PM me for details on teh PCB...have a few left.
Thanks
Thanks
Would Linear Systems LSK170B sub for 2SK170?
https://www.mouser.com/ProductDetai...70B-TO-92-3L-BK?qs=T%2BzbugeAwjjZsjTzJGs9IA==
https://www.mouser.com/ProductDetai...70B-TO-92-3L-BK?qs=T%2BzbugeAwjjZsjTzJGs9IA==
the forum is not letting me send you a private mesage cause my account is new, but I don´t have really nothing to post about to get it verified, could you please send me a pm to start the conversation about the pcbs John? thanks a lot 🙂
