Jared in MT
2 posts
Oct 05, 2011
7:57 PM
|
I picked up a gretsch 5222 super cheap.
It sounds good with harp, but is too quiet.
It sounds good with guitar, but not enough headroom.
Will install Nigels alnico magnet kit at some point, but would like to upgrade the speaker as well.
Alnico or ceramic speaker? Stay with 6" or cram in an 8".
Wife won't notice mods, but she will notice a different amp, so I have to work with what I've got.
Many thanks
----------
The good life alternates between sucking and blowing.
|
sammyharp
132 posts
Oct 05, 2011
11:04 PM
|
i highly recommend the alnico magnet kit when you get around to it. it improves this amp.tremendously. At this stage, I would definitely try switching out the tubes for something better. an old nos power tube will make a big difference. For the preamp tube, if you step down to a 12ay7 or 12at7, you'll get a more usable sound in the top end.The old rca 6V6's sound great! As far as the speaker, I would definitely suggest going with an 8 inch speaker with an alnico magnet. something you can do really easily without spending any money is lifting the tone stack. you only have to lift one side of 1transistor, and it sounds a LOT better and louder. if you do a search for lift tone stack and the amp name, you should be able to find a tutorial. Otherwise, let me know and i can post a link. These little amps are great and have lots of possibilities. have fun!
----------
|
5F6H
883 posts
Oct 06, 2011
9:25 AM
|
A more efficient speaker would be good, yes an 8".
5751 preamp tube. JJ6V6 are the tightest sounding of the 6V6 type tubes.
The amp is the same as the Fender Champion 600, really anything you do to help with regards to harp will probably adversely affect the amp's useability with guitar.
Lifting the tone stack will reduce headroom. I'd experiment with lifting the 2nd stage bypass cap (C10, it can always be replaced by adding another 25uf cap in parallel with R3 - arrow to ground). This should improve headroom & still keep enough gain for guitar & harp? EVEN LITTLE TUBE AMPS RETAIN POTENTIALY LETHAL HIGH VOLTAGE, don't dig about in there unless you are familiar with tube amp safety protocols.
Even for a 5-6W rated amp (it's really a bit less than this), it is a bit lacking in oomph. If you need significantly more volume/headroom you are really fighting the tide.
----------
www.myspace.com/markburness
|
Jared in MT
3 posts
Oct 07, 2011
6:19 AM
|
Thanks. I'll shoehorn in an 8" alnico speaker & magnet kit & dedicate it to being a harp amp.
I looked at several pages concerning lifting the tone stack and it seems like everyone had a different opinion, so I'll wait until I have a bit more expertise.
----------
The good life alternates between sucking and blowing.
|
sammyharp
133 posts
Oct 09, 2011
4:53 AM
|
the convienient thing about the tone stack lift is that it's easily reversable. If you don't like it, you just resolder the side you lifted.
----------
|
Jared in MT
4 posts
Oct 09, 2011
3:26 PM
|
Please post an appropriate tutorial. The ones I found were a bit perplexing. I do need to research some tube amp safety protocols before I fry myself, though.
----------
The good life alternates between sucking and blowing.
|
5F6H
886 posts
Oct 09, 2011
3:45 PM
|
Unplug the amp from the wall AC & let it cool for 10 minutes. Now you can change tubes without fear of getting burned or shocked.
You can now also remove the amp's chassis fairly safely, only touch the external parts of the chassis, NO internal components. Take a jumper wire with an insulated crocodile clip at each end, connect one end to the metal chassis or the ground point in the amp (where the AC cord ground terminates) connect the other end to either pin 1 or pin 6, AKA the plates, of the 12A#7 tube socket (count clockwise from the top side of the tube socket, where the components/ PCB connect. For other preamp tube types confirm which pin connects to the tube's plate before setting out to do any work). Leave the wire there for 30 seconds before touching anything else.
Remove the jumper before connecting to wall AC & powering up. Repeat the entire process before carrying out any future stages of work. Don't take any shortcuts.
Never power up a tube amp without the speaker connected, you will damage the amp severely if you do.
If all this is realy Greek to you, or makes no sense when you open the amp up - well this is nature's way of telling you to take the amp to a tech.
----------
www.myspace.com/markburness
|
