6l6 Tube question

[cap217]

I have a D style amp and the builder said:

This amp was built for 6L6GB or 5881 tubes. A good bias range would be 70-80% of MAX so 28-32Watts at idle.





I then searched for 5881s and came up with the Sovtek or Tung-Sol. I sent an email and asked what he recommends and he replied with:

I like the TAD 6L6GC STR short or tall and use them in my current production amps. REAL USA made Tung Sol 5881 from back in the day are what I sold the amp with.





So now I am confused. Can I use 6l6GC? What is the difference?

[Phil_S]

Find tube data sheets here: http://tubedata.itchurch.org/index.html
See for yourself!
6L6GC has a rated maximum of 30W.
6L6GB ... RCA 19W; Tung Sol 22W
5881...RCA 23W; Tung Sol 23W

If your amp idles at ~30W, it should probably have 6L6GC in it.

[cap217]

Find tube data sheets here: http://tubedata.itchurch.org/index.html
See for yourself!
6L6GC has a rated maximum of 30W.
6L6GB ... RCA 19W; Tung Sol 22W
5881...RCA 23W; Tung Sol 23W

If your amp idles at ~30W, it should probably have 6L6GC in it.

Thanks. I was thinking the 5881 handled more power but its the opposite. Makes sense now.

Should I lower the bias of a 6l6gc if the amp was designed for 5881s at lower wattage?

[Phil_S]

What is your negative bias voltage and plate voltage now?

[Stevem]

A 6L6GC is only rated for 30 watts so I would shoot for 75% once you`ve played thru the amp for a good 10 minutes and got everything up to normal temps.

[Teleguy61]

You can also look for 6L6WGBs, which are the same as 5881s.

I have gotten several very nice sets of JAN Phillips 6L6WGB, currently being used in my 100 watt HRM from CW:
clumpster@earthlink.net.
Great guy, good tubes, no BS.