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[angelodp]

Your creative work is terrific, congrats.....but the way it goes here is with respect and ' con calma ' as they say in the old country. You will get a lot more with honey than vinegar. Just ease into it. Post your results and convince us of your methods if its so important to have confirmation. This place is a gold mine of information and could well be a place that you form lasting friendships and find mentors.

This is not the TGP. Look out at the horizon.

[martin manning]

This is what Egnator used in his watts control and you can see this similar use on the Carlsboro 60TC labeled limiter.

Interesting, Mark, thanks for posting this. "Limiter" is a good name for it. It's shifting the bias point for both triodes, which results in symetrical clipping. The Carlsbro implementation is a bit more sophisticated than the diagram you originally posted in that it doesn't change the net value of the tail resistor.

[Murali]

Your creative work is terrific, congrats.....but the way it goes here is with respect and ' con calma ' as they say in the old country. You will get a lot more with honey than vinegar. Just ease into it. Post your results and convince us of your methods if its so important to have confirmation. This place is a gold mine of information and could well be a place that you form lasting friendships and find mentors.

This is not the TGP. Look out at the horizon.

Thanks for the props and the grounding thoughts, Angelo. Much appreciated.

[Murali]

doesn't the 33k across the pot make the effective value of the pot about 14k?

The resistance in parallel is 1/(1/Ra + 1/Rb) per my good friend.

Mark,
Yup, 14.28k. I did install the Engater-type in one of my EL34 'Wrecks tonight. It does change the feel of the amp some, but seems to maintain the tonality. I'm going to try it out at a hotel where the band has to be no louder than about 95 db (!).
Thanks for the tip and schematics.

Seems like using a 100k pot would be massive attenuation. I used a 10k pot and kept the values of the other components as they were in the amp. It's yielding about a 40% reduction. This amp also has a Pentode/Triode switch which can bring it down a little more.

[martin manning]

If you are looking to lower the volume in a transparent way, the Lar-Mar PPIMV (or KF Type-2, improved, if you like) is the best option. Clipping or biasing stages way down in the dirt with large cathode resistors will add its own kind of distortion and deviate from the amp's signature tone, as will triode-strapping the output tubes.

[Murali]

If you are looking to lower the volume in a transparent way, the Lar-Mar PPIMV (or KF Type-2, improved, if you like) is the best option. Clipping or biasing stages way down in the dirt with large cathode resistors will add its own kind of distortion and deviate from the amp's signature tone, as will triode-strapping the output tubes.

Thanks, Martin. Is there a schematic for this? Haven't found one on this forum. I understand the concept; used a dual 1 meg in a ppimv circuit on one amp and would like to see the lmppimv's circuit.

[Zippy]

Is there a schematic for this? Haven't found one on this forum.

I just did a search on "Larmar" or "Lar-Mar" and got 65 hits. It's there.

[martin manning]

Lar-Mar: https://tubeamparchive.com/viewtopic.ph ... highlight=

[Murali]

Lar-Mar: https://tubeamparchive.com/viewtopic.ph ... highlight=

Thanks again, Martin.

A more elegant solution than my primitive ppimv with dual gang 1 meg pot and "extra" caps.

[M Fowler]

Here is another layout.

[Murali]

Here is another layout.

Thank you, Mark.