Welcome, Guest. Please Login or Register
Decware Audio Forums
08/02/14 at 03:49:18


Pages: 1
Send Topic Print
What is the best heater voltage? (Read 3381 times)
Alex from Oz
Verified Member
**




Posts: 23
What is the best heater voltage?
01/05/09 at 01:02:51
 
G'day,

I've just finished my ZSP1 kit. Very happy with the sound.

I'm using the 6N1P tubes that came with the kit.
The voltage on the heater circuit is 6.97 volts AC.

What is the ideal heater voltage to use to ensure long tube life and what value resistor do I need for R7 & R8 to adjust the voltage?

Cheers,

Alex




Back to top
 
 
  IP Logged
Dan
Verified Member
**




Posts: 17
Re: What is the best heater voltage?
Reply #1 - 04/05/09 at 05:06:11
 
According to what I've read ~6 volts is ideal for tube life.  I don't know what 6.7 volts does to tube life versus anything other than ~6 volts.  

The pictures sent with my kit do not show a R7 or R8 resistor, and my Decware built SE84C+ does not have any resistors off the 6 volt transformer leg.  I'm going to have to measure the transformer voltage off the heater leg to determine if I need the R7 and R8 resistors.  

Dan
Back to top
 
 
  IP Logged
Dan
Verified Member
**




Posts: 17
Re: What is the best heater voltage?
Reply #2 - 04/05/09 at 16:12:47
 
I've checked out some more information on tubes-

it looks like the correct heater voltage depends on which tube you use.  About 6 volts if using 6N1P tubes appears to be correct for the ZSP1 kit.  Has anyone else noted that R7 and R8 are not shown on the Decware provided picture of the wired/soldered preamp?  Perhaps because the transformer measure 6 volts at that point?...  I'm a new toob boob so who knew?
Back to top
 
 
  IP Logged
Dan
Verified Member
**




Posts: 17
Re: What is the best heater voltage?
Reply #3 - 04/16/09 at 02:41:10
 
Is there anybody out there????......
Back to top
 
 
  IP Logged
Lon
Seasoned Member
****


"Love without
guts is
worthless!"
Philip K. D*ck

Posts: 7209
Re: What is the best heater voltage?
Reply #4 - 04/16/09 at 19:46:31
 
Sorry Dan and Alex. . . I'd help if I could but you both know more than ME.

Your best bet is for Steve to see and answer, or a private message to Eli. . . .
Back to top
 
 

Decware:ERR,HR-1,ZP3,CSP2+,Torii Mk III,PS Audio PWT+PWD MkII,PowerBases,PPP,AC-12 pcs, Denon DBP-A100, Denon DCD-A100,Rega RP3 +TTPSU,white belt+Exact2, VooDoo Cable:Evo,Ultra Linear, Iso-PodMapleshade:Double Heiix Plus.Samsonv2+v3 +4" platforms,Herbie's Iso-Cup
  IP Logged
Steve Deckert
Administrator
*****


If the 1st watt
sucks why continue?

Posts: 2370
Re: What is the best heater voltage?
Reply #5 - 04/21/09 at 17:30:33
 
The 6N1P, 6DJ8, 6922 family of dual triodes are spec'd for a 6.3VAC heater.  6 volts is OK all the way up to 7 volts, however tube life can be shortened somewhat at 7 volts, so it's best to shoot for closer to 6.

R7 and R8 are simply resistors in series with the heater load.  They are used to drop the voltage if it runs too high.  Also be aware that 6N1P's draw more heater current than either  a 6922 or 6DJ8.

Steve
Back to top
 
 
WWW   IP Logged
chopchip
Verified Member
**




Posts: 7
Re: What is the best heater voltage?
Reply #6 - 06/04/10 at 18:22:32
 
what is a typical value of r7 and r8

if i want to drop the voltage by .5 volts and the heater draws a current of 300 ma then .5/.3 = 1.7 ohms?

oh there is four heaters though they are wired in parallel so they draw 1200 ma in total so .5/1.2 = .42 ohms? that cant be right.

can you help plz?

thanks
Back to top
 
 
  IP Logged
chopchip
Verified Member
**




Posts: 7
Re: What is the best heater voltage?
Reply #7 - 06/04/10 at 21:30:30
 
when i measure from pin 4 to ground i get 3.5 volts.

is this correct?

thanks
Back to top
 
 
  IP Logged
Pages: 1
Send Topic Print