KT 170

Before you order a set, just be ware the KT-170 bottles are physically too big to fit in any PL amps, and many others. The amp will need to have especially wide socket spacing to allow the 170s to fit. 

johnss-
I imagine PL wouldn’t post this if that were the case
https://primalunablog.com/2020/10/30/tung-sol-kt170/

The KT170 will fit based on dimensions comparing KT 150
http://tungsol.com/tungsol/specs/kt150-tung-sol.pdf#:~:text=KT150,5.57%22%20%28141.5mm%29

https://vacuumtubevalues.com/wp-content/uploads/2021/04/KT170-datasheet.pdf

Pic of KT150 in PL
http://www.tonepublications.com/review/kt150s-for-primalunas-dialogue-hp-integratehttp://tungsol.com/tungsol/specs/kt150-tung-sol.pdf#:~:text=KT150,5.57%22%20%28141.5mm%29

4.5mm on each side(9mm difference) looks like it will be a tight fit, but I looked on my amp, and the front/rear tube spacing looks to be the concern. A call to PL to confirm is in order.

@tablejockey, one step ahead. I did contact PL a month ago asking about the 170s. Response from PL was no dice. 

Good job, johnss.

Saved me from a future $800+ purchase.

I have a Jolida 502A tube amplifier. I have had 6550, KT 88,  KT 120, KT 150 and now the KT 170. Prior to upgrading I would speak with Jared from Jolida, CEO of Black Ice Audio and each time he told me that my amp would be able to handle the upgrades. The KT 170 is a physically larger tube, not much room between tubes. They remind of me of a 300B tube. As to the sound, there is more of everything there, except noise. I find myself not using as much volume as I used to, there is deeper and more natural bass, a wider soundstage and a little cleaner in the highs. I have had them for about 4 months and no problems with the tubes. The other tubes are 12AX7-Mullard reissues and 12AT7 Mullards. I am happy with them. Prior to buying them, I would contact the manufacture of the amp to see if the amp can handle the tubes. I hope this helps some of you.