Question about PP EL34 power supply behaviour

[fdegrove]

Hi,

Wayne,

You could try a 1N4007 in series with a dropping resistor in place of the choke.

Even just a diode in series with the PS and followed by some capacitance will do a good job already.

I once put the question here on the forum as I had a 1N4007 in the PSU as described and had completely forgotten why it was there.

Nobody seemed to know the answer but it turned out that this trick is rather popular with the guitar amp guys.

Cheers,

[cogsncogs]

Hi Frank,

I did that back when I was teenager to my amp without having seen that done. Just by playing around and trying to use logical deduction. And lo and behold I read about it in the glass shards dept. of Glass Audio magazine! I thought to myself, Hey I invented that! Of course I know better!

Wayne

[cogsncogs]

Hi arnoldc,

the amp i prototyped got a very good midrange in which i was surprised myself. however, it definitely is lacking in the bass department, more so low bass. it is like it's there but it isn't. like running out of steam if i may say.

Well your output iron has a great influence in the bass department, as does a lot of other things. How much feedback if any, coupling caps, and any other RC time constants etc. I wouldn't order new iron just yet.
Do you have a schematic of you're current set up so I can have a look at it? That would help a lot. You can zip it up and email it to me if you like. I could email you a schem of mine.
5k opt is a good choice. 6k6 opt will give you slightly less power and lower distortion. Depends a lot on your operating point. Core saturation could be your problem and here again this is where a scope comes in handy. It's OPT design dependent.
I hope we can help you here. Of course we all could use use a little help now and then!

i'd appreciate if you could share your experience on this having built that magnificent PP amp of yours.

Flattery will get you anywhere!

Wayne