Bottlehead Forum

Bottlehead Kits => Legacy Kit Products => Topic started by: Cary on October 09, 2016, 12:36:55 PM

Title: 6CG7/6FG7 in Foreplay 2?
Post by: Cary on October 09, 2016, 12:36:55 PM

Can the 6CG7/6FG7 be used in the Foreplay2? If so what mods need to be done?

Title: Re: 6CG7/6FG7 in Foreplay 2?
Post by: Natural Sound on October 09, 2016, 01:21:08 PM

The only thing I'm wondering is if the heater supply is beefy enough. As I recall the FP2 had a pretty small power transformer. From what I gather the 6CG7 draws almost twice the heater current. Aside from that it should work. Several users have modified FP3's to run 6CG7's.

http://bottlehead.com/smf/index.php?topic=3609.msg33283

http://bottlehead.com/smf/index.php?topic=1412.msg9956

Title: Re: 6CG7/6FG7 in Foreplay 2?
Post by: Paul Joppa on October 09, 2016, 02:41:28 PM

I can't locate any notes with details of the power transformer. The transformer itself may have ratings - take a look!

I do sort of recall that there was not enough heater current available to make a DC heater supply. I know this was true of the Foreplay 1, and I believe it was also true of the FP 2. People were trying separate wall-wart type DC supplies for this reason. The last version (3) used the much larger PT-3 in order to have plenty of heater current reserve, and it came stock with the DC heaters.

Title: Re: 6CG7/6FG7 in Foreplay 2?
Post by: Paul Birkeland on October 10, 2016, 07:14:10 AM

I can confirm that the stock power transformer on the Foreplay I and Foreplay II will not support the heater current demand of a pair of 6CG7's.