resistor on secondary - 32Ω load

[Chuck H]

Regarding the "line out", it's as easy as this...

Decide which secondary tap you wish to run it off of. Figure the voltage at full output for that tap (Ohm's law). Then voltage divide with whatever resistance gives the right ratio to a 100r or 500R resistor to achieve about 1 volt, which is close enough to line level. I prefer to target about two volts using a 500R pot as the divider shunt. This allows me more usable signal at lower volume levels and I can always dial it down with the pot if I'm cranking the amp.

[g1]

But why then do you need this additional load resistor? Do you need to unplug speakers during operation?

BTW, without input signal standard shorting speaker jacks are safe enough.

Shorting jacks will not help if speaker cable or speaker goes open.

[Chuck H]

Shorting jacks will not help if speaker cable or speaker goes open.

Or if a dummy load of any kind fails open.

[Helmholtz]

I'll use speaker emulation impulses.

Would you mind to explain?

[Guitarist]

Ah sure, makers send a burst of sound out and measure the difference, hence it's an impulse. This is too short an explanation, I know So I'd record the guitar --->amp---> Load/Line Out ---> into Interface and then use a plugin and toggle through some different Celestial impulses. Hopefully it's a good tone overall but I'm not totally sold yet. It does make practicing fuss-free though.

Here's such a co. They send you the file via email after a sign up: https://www.redwirez.com/free1960g12m25s.jsp

[Gaz]

The idea with the 32 Ohm resistor is not great. Better idea would be to use a shorting speaker jack and attach the dummy load resistor to the shorting lug. When no speaker cable is plugged in the resistor is on the secondary, and when you plug in the speaker cable it lifts and the amp operates normally. Simple. That way, you an make the dummy load 16 Ohm (you will need one that can handle the amp's full output, of course), and the amp still puts out full power, and sounds normally when you have a speaker plugged in.

But I still think it's not a great idea using impulses. If you've ever compared a reactive load to a resistive one, then you know the difference is significant. The Two Notes Torpedo Captor is a little over $200 and well worth it if you are going to be doing recordings that way.

[Guitarist]

That is a brilliant idea and why didn't I think of that!

[Gaz]

No problem! I got it from the Garnet Herzog!

[d95err]

I like to put a safety resistor of 200 to 1k directly across the OT secondary wires. That way, I’m safe in case if failures or intermittent connections for the jacks, impedance switch or anything connected to the amp output.

I’m fine running the amp with only the safety resistor, but normally I keep the Torpedo Captor plugged in to get a reactive load.