Silly rocket volume output question

[yalesmith]

I have built the express, liverpool and the rocket. The rocket sound great but when compared to the others 2 amps it is has very low volume....any ideas? i switched tubes around and it wasn't the tubes, I thought the rocket and LIVERPOOL are similar in terms of output. but the liverpool is a lot louder than the rocket ...Any ideas?

[xtian]

Start reporting your voltages, please. The two Rockets I built are loud and strong. Something's wrong with yours, youbetcha.

[yalesmith]

Sorry for the delay but you know how life is sometimes unexpected things happen. I think the voltages are cool but let me know if they seem crazy to you.

Thanks again!

[Colossal]

You're EL84 plate voltages look pretty low!

[yalesmith]

the voltage guide in the tw files area indicate that the voltages should be 285, I don't think 10 volts should make a difference, especially with how rectifier tubes vary

thanks

[Koop]

Could it be a speaker sensitivity issue? Same speakers?

[yalesmith]

yes same speaker....it is very odd. but i do find the triode dynaco OT a bit odd to work with

[M Fowler]

The Dynaco A470-S is a great performing OT I use it in many different styles of amps including a Marshall JCM800.

I think you need go through the circuit closely and figure out exactly why it's not giving the perceived volume level you want.

Mark

[yalesmith]

I love the dynaco is sounds great, it was a little weird with the the odd set of OT primary..... It just odd that the voltages are okay but volume is low....I wonder if it can be a faulty impedance switch.

[Colossal]

the voltage guide in the tw files area indicate that the voltages should be 285, I don't think 10 volts should make a difference, especially with how rectifier tubes vary

thanks

I just looked it up and you're right. 285VDC seems low but it's right! Stand corrected.

[yalesmith]

here is a pic of my build, not sure if this will help.

thanks!

[JazzGuitarGimp]

If the output is just low in volume, and not abnormally distorted, I'd be looking at the voltage swing at the output of the PI. It sound like you may not be hitting the output tubes hard enough.

[JazzGuitarGimp]

Also, 13.6V on all the control grids (pin 2) doesn't make sense to me: these grids should be referenced to GND. Check to make sure the junction of R17 and R18 is really tied to GND.

[yalesmith]

13.6V on all the control grids (pin 2) doesn't make sense to me either, the junction of R17 and R18 are tied to GND....... this is so annoying to me, these are the things that drives me crazy.

[M Fowler]

Is your volume control wired correctly it looks like the red wire is going to the board it should go to ground.