Hey, hope all is well!
I'm planning a build that started out as a 5f2a but now with a BF tonestack and NF.
This will be mostly used at home as a pedal platform for Kingsley pedals to get a good sound at low volume at home. I decided to use power scaling on the power amp only to be able to get the amp working a bit while clean and not just cracked on with the volume control. I also decided against the VVR/Mosfet type power scaling as I dont want to worry about failing Mosfets.
I have had a custom power transformer made from http://www.transformerequipment.co.uk/ for £113 delivered, If you are in the UK and need a custom spec transformer, I would definitely recommend them!
The transformer has 2 secondaries:
250 - 110 - 55 - 25 - 0 at 75mA
250 - 0 at 75mA
This should yield me: 5, 1, 0.25 & 0.05W
The multiple powered secondary will be switched by a rotary switch and feeding a bridge rectifier and then the power section. The seperate 250v will feed into a seperate bridge rectifier and then the pre amp.
As there isn't sag with a SE amp, I've used a large reservoir cap for reduced hum and bass response, using 30uF for the rest for bass handling also.
Have a raw princeton cab on the way that I shall be covering with the cool paisley fabric
I've done some tests and using Titebond works well to glue the fabric to wood with no seeping through the fabric. I did try using a satin poly varnish over it, but it darkened the fabric way too much and made it look pretty smudged. I then tried using multiple coats of shellac (1:4 cut) and that worked really well, didnt darken it too much but sealed off the fabric and firmed it up, so will be using that on the cab!
For tubes I have some mil spec brimar 6v6 and 12ax7:
And for the speaker I shall be using a Celestion G10 Greenback, probably not the most popular choice for this type of amp, but I just love the greenback speaker! I have broken it in using a 15hz signal for 24 hours.
I shall be updating my progress and parts come in and the build progresses
If someone could check over my layout for stupid mistakes, I would greatly appreciate it!
Cheers!
I'm planning a build that started out as a 5f2a but now with a BF tonestack and NF.
This will be mostly used at home as a pedal platform for Kingsley pedals to get a good sound at low volume at home. I decided to use power scaling on the power amp only to be able to get the amp working a bit while clean and not just cracked on with the volume control. I also decided against the VVR/Mosfet type power scaling as I dont want to worry about failing Mosfets.
I have had a custom power transformer made from http://www.transformerequipment.co.uk/ for £113 delivered, If you are in the UK and need a custom spec transformer, I would definitely recommend them!
The transformer has 2 secondaries:
250 - 110 - 55 - 25 - 0 at 75mA
250 - 0 at 75mA
This should yield me: 5, 1, 0.25 & 0.05W
The multiple powered secondary will be switched by a rotary switch and feeding a bridge rectifier and then the power section. The seperate 250v will feed into a seperate bridge rectifier and then the pre amp.
As there isn't sag with a SE amp, I've used a large reservoir cap for reduced hum and bass response, using 30uF for the rest for bass handling also.
Have a raw princeton cab on the way that I shall be covering with the cool paisley fabric
I've done some tests and using Titebond works well to glue the fabric to wood with no seeping through the fabric. I did try using a satin poly varnish over it, but it darkened the fabric way too much and made it look pretty smudged. I then tried using multiple coats of shellac (1:4 cut) and that worked really well, didnt darken it too much but sealed off the fabric and firmed it up, so will be using that on the cab!
For tubes I have some mil spec brimar 6v6 and 12ax7:
And for the speaker I shall be using a Celestion G10 Greenback, probably not the most popular choice for this type of amp, but I just love the greenback speaker! I have broken it in using a 15hz signal for 24 hours.
I shall be updating my progress and parts come in and the build progresses
If someone could check over my layout for stupid mistakes, I would greatly appreciate it!
Cheers!
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