5e4a super with 4 6v6's

[galtjunk]

I have a 1956 5e4a that has had an old recap job and the speakers were replaced with 70's CTS.
It is by far the best sounding Tweed I have ever owned, and I've had quite a few.
I also have a 5F4 built from a Mojo kit that has 6L6's and Weber alnico 10a125's .
A friend heard the 5E4a and wanted something like it but with more head room. He didn't want the 5F4 that used 6L6's.
I built a 5e4a/5f4 using 4 6V6's for him.
I used Bassman iron and just added 2 more octal sockets for the extra tubes.
I used 3 500v 20uf caps from F&T for the first 3 caps and a Sprague Atom 475v 8uf.
I used Mallory 150's and 1 watt carbon film resistors.
I used a 19x8x3 chassis in a tubes up head configuration.
I used 3 JJ 12ax7s, 4 JJ 6v6 and a JJ 5U4GB.

It sounds great to me with the highs being much smoother than the 5F4 and it is very much like the 5E4A, just louder.


If I was building it for me, it would be done. I like it as it is.


He would like to get a little more head room and a little less mids.


How Will changing the first 1 or 2 12ax7's to 12ay7's affect it?

How do I decrease the mids with no mid control?

Where should I set the bias and will this setting affect the head room?

14/415*.7=23.6 9.8 watts
14/415*.8=26.98 11.2 watts
10/415= 24.09 10 watts

Almost all of his guitars use P-90's.

He is a well known player from the Boston area with records from the 80's and a very recent new release.
The group he is with recently showed on Jools Holland during their tour of Europe.


When I get it done I will post a video of him using it.

Thanks

[xtian]

What speaker(s)? Changing speakers might be a better solution for the mids than a circuit change.

[galtjunk]

He uses a 2 12 cabinet.
I know that one of the speakers is an Eminence Wizard.
I'll have to ask about the other.

[PaisleyTube]

Tweaked a 5F4-clone (not build by me) some time ago for a prof. player needing more headroom over here, part of the tweaks (besides transformers, removing "mistakes", etc.) was using 12AY7s for V1 and V2.

[galtjunk]

Tweaked a 5F4-clone (not build by me) some time ago for a prof. player needing more headroom over here, part of the tweaks (besides transformers, removing "mistakes", etc.) was using 12AY7s for V1 and V2.

Thanks,

I'll try that and see how it works out.

[pops]

I did a tweed twin and ended up using 4 6v6's, all 12AY7's and no bypass caps. Was very warm and still plenty loud.

[galtjunk]

Here it is.

I tried 12ay's in v1 and v2 and that works out great for p90's.
Here are a few pics.

Weber Tweed bassman iron.

The faceplates are from a local trophy shop.

The chassis is from Dirtydawg. I hope he gets back up and running soon.

The cab came from Ebay as an unfinished custom routed British head cabinet. The guy does quality work.
$80 for a baltic birch finger jointed cabinet.
$15 extra for the pair of additional routs. The front rout and the top vent.
The shipping was a little steep but the quality is great.
His ebay id is Adams713.
Search for British style head cabinet.

I will be changing out the grill cloth to perforated stainless steel.

[pops]

I built a tweed twin for a friend and ended up using 4 6v6's all 12ay7's, no bypass caps, tho you could switch them in and out. You could also switch the mid resistor to another value to vary the tone. was a great amp and still plenty loud.