2sk170 vs lsk170 which is better in sound quality?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Member
Joined 2002
Paid Member
From where? The guys from LS bend over backwards to help the DIY community, the ones I've measured were very close and the latest batch of SJ74's (the ones that Linear Audio gave a sample of) were close to 2SJ74's as well.

That is very true. We are very fortunately to be able to get these parts
at all since there is such a high demand for them. My understanding is
that (as of BA2015 last fall), the diyaudio shop is basically the only
non-OEM receiving these.

Dennis
 
Right, if it does not make any difference to you, then what good others' opinion do to you.
I had diamond ears once, but now they are downgraded to bronze. I wouldn't hear any difference in sound quality.

Wow, you should have sold your ears when they were diamond, a few oz of diamonds would allow for big heatsinks and toroidals for many amplifiers!
Bronze isn't that valuable, but you could smelt and forge a nice volume knob with it!
 
There was some opinion on this Forum that the lsk was not as quiet as the 2sk.
The datasheet says the opposite.
There was some opinion on this Forum that the quality control of the lsk was not as good as was for the 2sk. The efforts Linear seem to put into getting the "process" to yield good components seems to say otherwise.
 
Disabled Account
Joined 2004
There was some opinion on this Forum that the lsk was not as quiet as the 2sk.

I posted a plot a long time ago that showed genuine Toshiba parts are not immune to having excess noise. Unfortunately I'm not sure I have access to a QuanTech anymore so apples to apples comparisons are difficult. You need to make sure you are operating at the same transconductance for a fair noise comparison. So far as far as I can tell the lsk parts should show theoretical behavior in the flat noise region as do the 2sk parts. I presented some data in my Linear Audio microphone article where they were remarkably close to theoretical.

There seems to be too much emphasis on getting the Idss range, the first date code of lsj74's had highish Vp's so the beta parameter was low and they need more Id to get the same noise.
 
Last edited:
I posted a plot a long time ago that showed genuine Toshiba parts are not immune to having excess noise. Unfortunately I'm not sure I have access to a QuanTech anymore so apples to apples comparisons are difficult. You need to make sure you are operating at the same transconductance for a fair noise comparison. So far as far as I can tell the lsk parts should show theoretical behavior in the flat noise region as do the 2sk parts. I presented some data in my Linear Audio microphone article where they were remarkably close to theoretical.

There seems to be too much emphasis on getting the Idss range, the first date code of lsj74's had highish Vp's so the beta parameter was low and they need more Id to get the same noise.

Measurement wise I agree the fact it might be very close but did anybody compared sonically how is the difference?
 
The sound of the LSK170 has more refulgence, but seems to be a touch obsequious in comparison with the original Toshiba parts. When playing a recording with plucked strings, the Toshiba parts give more of a sense of the guitarist's hangnail, whereas his halitosis is better expressed through the LSK transistors. It's like the difference between pudding and licorice.

This all assumes a 6k8 drain resistor. Change that to an 8k2 and all bets are off.
 
The sound of the LSK170 has more refulgence, but seems to be a touch obsequious in comparison with the original Toshiba parts. When playing a recording with plucked strings, the Toshiba parts give more of a sense of the guitarist's hangnail, whereas his halitosis is better expressed through the LSK transistors. It's like the difference between pudding and licorice.

This all assumes a 6k8 drain resistor. Change that to an 8k2 and all bets are off.

LOL. I had to look up the definition of "refulgence." Always good to expand one's vocabulary.

I do remember member EUVL once saying that he would stick with Toshiba parts (vs. LS) but I don't recall why.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.