How does the EQ switches work?

What speaker have you paid it with?

Have you made a head cab?

Sorry with the many questions, but wow, what a great build.

Actually Nik can make external bias probe sockets to read bias current easily.

I can do that on the JTM45, but I'm rather apprehensive about opening up the chassis and checking anything, especially probing around knowing there's 400+ v in the circuits. Due to my lack of electronics knowledge, I rather not get shocked to death.

If there's anything wrong, I can usually just bring it up to Nik, but as yet nothing's gone wrong.

If you're using Shuguangs, which are real KT66s. Here is the datasheet from analogmetric .

It's a 25W tube, but max plate voltage stated is 500V. So I'm not sure exactly what Nik's got on the plates for his 45/100.

Clone of the Tr@inWr3ck Rock3t.

replace the numerics and alias with the equivalent in alphabet and google it

Ah alright, thanks.

Isn't that bias values v high for a JTM45/100?

Here are some replies on the same topic on the metro forum:

http://forum.metroamp.com/viewtopic.php?f=15&t=16926

Might wanna ask Nik what the plate voltages are, then from there work out the bias values.

For 560V plate voltage on the JTM45/100, at 70% , they recommended 30mA. So first e-mail I'll do is to shoot Nik asking him for recommended bias values on his circuit.

Yup, they're rated at RMS, but there's a way to calculate the actual output. George from metro did run thru it before. Something about using some meter on the output and sending a sine wave thru the input.

Then doing some calculation.

If you every do get to find out what's wrong, please do let Nik know, he continues to develop and refine his products based on customer feedback. I'm sure he'll want to know what's the problem and help you solve it.

Thanks hywelg,

Btw, I gather that a JTM45/100 B+ should be high, 500V? Or thereabouts, but I see the PT in nik's layout  supplying 360V, noob question, but how did 360V get to 500+? I think this is the plate voltages.

I know after rectifying, you get whatever is put into the rectifier circuit. Albeit peaky and what not which requires filtering.

NP, I too wish to learn like you.

Its great that you've contributed to this thread.

I have no idea where B+ is located in any amps, but from what I've gathered, its the voltage supplied to the circuit.

I've a couple of Nik's amps and would like to get the JTM45/100, just that I'm not sure what to pair it with.
And Nik doesn't make 4x12s, so getting a suitable cab and speaker combo here is kinda tough.

Btw Seeker, are you or any amp tech in your area able to measure the RMS and peak output of this beast?

Time to pair in a 1960AHW

I have the JTM45, am looking to get the 45/100 in the near future.

The ghost notes is probably the speakers, rather than the amp?

I think the speakers in the HW 1960B are G12H30 Heritage.
Ouch! 120W handling, probably the cause of the ghost notes.

Have you tried it with a regular 1960B? Those loaded with G12T-75s. Those are rathed 300W handling.

Btw, thanks seekers.

I'd like to hear some opinions of the JTM45/100 that Nik produces.

What cabs go great with this?

Marshall 4x12 with G12T-75?

Nik,

The faceplates are sweet and about time.

haha.

What was the sonic difference between the Ceriatone trannies and the matchless?

Thank you, it is greatly appreciated, no rush though, whenever you have the time.

While you were recording, could you also do a "demo" on how the input gain works.
Like just strum an open G while turning up the knob.