A nicer Blues Junior

[duriehill]

Hello all

Seeking your advice.. I have a Blues Junior, which I've modded and tweaked. I've never really been really happy with it though. It was the first amp that I bought because of $£$.

I do like the general tone of the amp, and it does sound sweet now that I have tweaked it. But deep down I'm annoyed with the restricted sound of it. And I find it noise prone.

I'm thinking of removing the PCB and building a similar fender style amp trying to use as much of whats there, but hopefully improve on the boxiness and noise floor. And keep it Fender-y

Any ideas? :?

[xtian]

It's the box! Seriously. I hate BJs because of the size and shape of the cabinet. And the noise inherent in combos! Build a head, and get a decent speaker enclosure.

[DonMoose]

It's the box! Seriously. I hate BJs because of the size and shape of the cabinet. And the noise inherent in combos! Build a head, and get a decent speaker enclosure.

Instead, I'd say keep the combo - upgrade the speaker later - for grab-n-go things, but get/build a speaker cab. 4x12s are going for $150 to $250 around here (pawn shop) for nice clean ones.

[duriehill]

Cheers gents

Maybe boxy wasn't the right word for me to use. It's a kinda restrictive, farty quality these amps seem to have.

The tone with this aside is quite pleasing with 'upgraded' components and an Jensen C12N. I use a Canabis Rex too or occasion.

I'm actually thinking of designing a point to point layout for it to clean up the noise floor etc OR actually giving up on the BJ all together and building a classic fender circuit in the existing chassis and cab.

[Firestorm]

The ribbon cables in those things are the source of all sorts of trouble. If anything, route the various leads where they should go instead of where it was convenient to assemble them.

[Phil_S]

... And keep it Fender-y
Any ideas?

I might help to give us a little more to go on. "Fender-y" can be a range of things. Do you want a Deluxe or a Princeton? Something else? Converting the BJ circuit from PCB to PTP, IMHO, won't do much for you as the basic tone circuit won't change.

Maybe it would be better if you tell us what sort of music you like to play and what artist's tone you like.

If it were mine and I wasn't satisfied after a speaker change, I think I gut it and put another amp in the chassis.

How far are you prepared to go budget-wise? Do you want to reuse the transformers? If so, that sets some limits -- not necessarily a bad thing, but it's a factor. If you have a clean slate and are willing to spring for new iron, that will open up more options.

How important is the reverb?

[Milkmansound]

I would just gut it and built a tweed 5E3 circuit in there and call it a day.

The BJ always sounded like dental work to me - saw blade distortion, papery cleans, and the reverb sounds like you threw a tin can down a hallway.

Add on reliability issues and you've got a real stinker.

The cabinet is about the same size as a 5E3 and that is a very simple circuit even for beginners. You can probably reuse the power and output transformer and use the mini 9 pin output tubes so that you can re-use the chassis. The 5E3 is a very responsive and interesting amplifier - only has one trick up its sleeve but its one hell of a trick!

[duriehill]

Yea, you're probably right on gutting it. I'll probably never by entirly happy with the BJ, even if I do rebuild it beautifully haha.

I'm thinking I'll go down the 5e3 route. I don't really have a budget, but if I could use the existing iron that would be good. Actually, I hate the PT so I'll probably replace that.

There just seems to be something inherently wrong with the design of that amp. I wonder where that circuit came from? Does anyone know the history of it?

[Randy Magee]

Several people have used the Blues Jr. as a platform for building an 18 watt variant.

[duriehill]

Looking more into building the 5e3, using what I can from the blues junior carcass, I'm looking at whether I can recycle the blues junior OT:
http://www.bluebellaudio.com/EDB1750F.pdf
in the 5e3 cicuit.
The ideal OT is:
http://www.bluebellaudio.com/EDB1750E.pdf

To me it looks like the difference between the two is that the BJ OT is 7K and the 5e3 is 8K.

Do you think the BJ OT could be adapted for the 5e3?

[Milkmansound]

if you stick with EL84s then yes

the end result would be something between a 5E3 and Marshall 18W

if it were me, I would do the tweed circuit. The 18W is kind of a "meh" amp to my ears. The Deluxe suits my style of playing more

[duriehill]

So went ahead and gutted the Blues Junior using the chassis and cab for a Tweed Deluxe build.

See pics

[sliberty]

Looks nice, but you didn't tell us how you like the tone

My experience with Blues Juniors is that the cabinet is actually not a big problem. The speaker can be improved. But the big problem is the overdrive circuit. The BJ sounds pretty good clean, but overdriven , not so much. The more you overdrive it, the worse it sounds.

I have built a Brown Princeton Amp circuit into a BJ cabinet with a JBL K-120, and it is stellar. I am currently building a Blackface Princeton into another BJ cabinet (tone quality TBD). The cabinet dimensions yield acceptable tone in a perfect grab and go format.

I would imagine that your 5E3 is pretty cool, although to tell you the truth I am not a huge fan of that circuit. Not enough clean level for my taste. But the overdrive is sweet and creamy, which you certainly can't say about the BJ.

Enjoy!

[duriehill]

The tone is rich and complex. I love the amp, the circuit is so much fun - for something simple if seems to have a big tonal range!

Yep, I was not a fan of the blues junior OD.