Bill M mods Blues junior.

markj

Has any body on the forum done any Bill M mods to their Blues Junior. I have a Ltd edition fitted with a Eminence cannabis rex speaker. Its a great amp but sounds a little sterile. It may sound better when the speaker has broken in more. Was wondering If any of the mods would be worth doing.

stickyfiddle

I had a BJr with some of the BillM mods and it was a cracking amp- fecking loud and basically awesome, though that may have been at least partly due to the replacement speaker.. I can't remember exactly which mods it had beyond the "twinstack" one though. 

Gagaryn

I did a few of the simple mods on mine, changed a couple of wires on the power transformer so it was set to proper voltage, the twin stack mod and changed the master volume pot to one with a different taper so it could be turned past 3 at home! I had a V30 in mine, it sounded alright!

Jalapeno

Most of the mods are for Mk1 / Mk2 models.

I've tried valve swapping to clean it up a bit, sounded crap tbh.  I have a Sunburst with a Cannabis Rex - sounds great - turn it up !!!!!

Loobs

What does sterility sound like? 

noisepolluter

Jalapeno said:

Most of the mods are for Mk1 / Mk2 models.

I've tried valve swapping to clean it up a bit, sounded crap tbh.  I have a Sunburst with a Cannabis Rex - sounds great - turn it up !!!!!

Was meaning to ask you how you were getting on with the speaker. 

A mate of mine has some of the BillM mods in his, although he kept the stock speaker and plays much more overdriven stuff than I do, so I wasn't really able to get an idea of how much difference the mods make. 

One thing I do think could definitely do with upgrading is the reverb tank - I find the stock one really bright and crashy. 

The circuit seems a bit noisy too, even if the volume and gain are completely off. Anyone else find this.

Gagaryn

The reverb isn't great, it's quite a short tank which I think might be the main reason. I never tried changing mine though - changed the amp instead!

stickyfiddle

Loobs said:

What does sterility sound like? 

I think it's the opposite of "fruity"

Heartfeltdawn

Loobs said:

What does sterility sound like? 

It sounds like every amp that doesn't have a crystal lattice structure inside. 

noisepolluter

Gagaryn said:

The reverb isn't great, it's quite a short tank which I think might be the main reason. I never tried changing mine though - changed the amp instead! 

If the MOD/Ruby tanks were actually easy/cheap to get hold of in the UK, I might have been tempted to give one a punt. Unfortunately the shipping from the US is more than the cost of the tank! 

I ended up getting a secondhand Hardwire reverb for really swampy stuff. 

ThePrettyDamned

Best BJ mod:

http://www.andertons.co.uk/combo-amps/pid19426/cid691/fender-hot-rod-deluxe-iii-40w-tube-combo-with-reverb.asp?LGWCODE=19426;56375;2717&utm_source=googlebase&utm_term=2230204000&utm_medium=pricecomp&utm_campaign=GoogleShopping&gclid=CMWH7_LF270CFekBwwodQasAaw

Sessionman

I have a lot of experience with the Blues Junior and have one in my workshop.  It is a little sterile and the speaker breaking in will not cure it.  It simply lacks bass and would benefit from some of the coupling caps being upped to higher values... particularly post distortion.  I find it somewhat 'lack-lustre' as factory issue.

There are many BJM mods to improve it... but they all add up in costs greatly if you cannot fit them yourself.

I do have a Cannabis Rex speaker (I have a stock of many speakers for R & D purposes), but I found it makes the BJr sound like it's playing through a blanket (IMHO being a twang fan).  I much prefer the old standard Fender gold/brown label speaker... which is really an Eminence Legend 1258 badged as Fender.  The Lightning Bolt speaker in the MkIIIs is rather flat sounding (I have one in a BJr cabinet).

The cabinet is made from chipboard (not MDF as regularly stated) with a 12.7mm ply baffle.

Fender really need to respond to customer opinions about this amp and seriously update it!  Get rid of the boxy tone... but they sell so many!  Not because it's great, but because it's a budget Fender valve amp, and they probably think 'if it ain't broke, don't fix it (majorly).  They keep playing with it around the edges, but it never gets any better really.  The updrades just make people think it will be 'much' better and live in hopes!  When for me, it just gets worse!  The pots break as soon as you like, or anything falls on it's control panel.  They're not secured by nuts like most amps!  A nasty cheap trick to save a few cents!

Of course, it's small, affordable and very portable, which I have to say, is the largest reason for its popularity.

The older MkI & II versions have an American made Accutronics 8EB2C1B short triple spring reverb pan which are poor in tone.  MkIII BJrs employ the latter 'Made In Korea' reverb pans, same part number, black finish, but sound more lush and 'hall-like'.

For me, there are better amps on the market designed to overcome the limitations of the BJr and its low quality build.

Jalapeno

I am loving the the Cannabis Rex speaker tone, it is great for edge of break-up sound @Noisepolluter

IMHO gets rid of the boxiness

allicio

Ive got one of the fsr mkiii's that came out a year or so. Ive upgraded the speaker to a tayden high Brit as I wanted a bit more warmth.
The only billm mod ive done is move the ribbon cables away from everything else ala bills site.
A tech also converted it to 240v for me which is the one essential mod as fender spec it to European voltages.
I have no hiss or noise of any kind. Dead silent.

Sessionman

The official UK mains voltage is now 230Vac... it has been for many years.  Every product designed for sale within Europe, must work on 230Vac ±10%.  So that's 207 to 253Vac.  Under EC regulations, manufacturers have no option but to comply with this directive or risk having their products impounded by Trading Standards, who police these regulations.

Voltages around the UK are not 'supposed to be' 240Vac, but can be in certain areas.  The law allows it to vary between 207 and 253Vac!

Frankly, there should be no need to have equipment modified to run on 240Vac.

Just wanted to clear up this misnomer.

Gagaryn

Sessionman said:

The official UK mains voltage is now 230Vac... it has been for many years.  Every product designed for sale within Europe, must work on 230Vac ±10%.  So that's 207 to 253Vac.  Under EC regulations, manufacturers have no option but to comply with this directive or risk having their products impounded by Trading Standards, who police these regulations.

Voltages around the UK are not 'supposed to be' 240Vac, but can be in certain areas.  The law allows it to vary between 207 and 253Vac!

Frankly, there should be no need to have equipment modified to run on 240Vac.

Just wanted to clear up this misnomer.

Yeah, I'm aware that the 10% tolerance meant that no changes were actually necessary as a reult of the 230V harmonisation. If IIRC the main reason for the mod (simply switching a couple of wires) is that BJr have the Bias set pretty hot and changing the voltage results in a drop in plate voltage.

martinw

The actuality is that the UK still runs on 240V...nothing in terms of distribution hardware has changed, only the specification which allows us to 'harmonise' with Europe.

Allowing for tolerance, the vast majority of the country will be around and about 240.

Virtually all the modern Fenders I've seen have a 240V tap on the mains transformer, so it makes sense to use it and I change all those that come through my workshop. It can only be a good thing to lower the secondary voltages to closer to the design spec.

The Blues Junior in particular, as @Gagaryn says, runs it's EL84s on the hot side, and benefits from this.

jpfamps

martinw said:

The actuality is that the UK still runs on 240V...nothing in terms of distribution hardware has changed, only the specification which allows us to 'harmonise' with Europe.

Allowing for tolerance, the vast majority of the country will be around and about 240.

Virtually all the modern Fenders I've seen have a 240V tap on the mains transformer, so it makes sense to use it and I change all those that come through my workshop. It can only be a good thing to lower the secondary voltages to closer to the design spec.

The Blues Junior in particular, as @Gagaryn says, runs it's EL84s on the hot side, and benefits from this.

I would agree with this completely; I also always rewire Fenders to 240 if there is a tap available.

To not do this, is in my opinion daft.

jpfamps

Sessionman said:

I have a lot of experience with the Blues Junior and have one in my workshop.  It is a little sterile and the speaker breaking in will not cure it.  It simply lacks bass and would benefit from some of the coupling caps being upped to higher values... particularly post distortion.  I find it somewhat 'lack-lustre' as factory issue.

There are many BJM mods to improve it... but they all add up in costs greatly if you cannot fit them yourself.

I do have a Cannabis Rex speaker (I have a stock of many speakers for R & D purposes), but I found it makes the BJr sound like it's playing through a blanket (IMHO being a twang fan).  I much prefer the old standard Fender gold/brown label speaker... which is really an Eminence Legend 1258 badged as Fender.  The Lightning Bolt speaker in the MkIIIs is rather flat sounding (I have one in a BJr cabinet).

The cabinet is made from chipboard (not MDF as regularly stated) with a 12.7mm ply baffle.

Fender really need to respond to customer opinions about this amp and seriously update it!  Get rid of the boxy tone... but they sell so many!  Not because it's great, but because it's a budget Fender valve amp, and they probably think 'if it ain't broke, don't fix it (majorly).  They keep playing with it around the edges, but it never gets any better really.  The updrades just make people think it will be 'much' better and live in hopes!  When for me, it just gets worse!  The pots break as soon as you like, or anything falls on it's control panel.  They're not secured by nuts like most amps!  A nasty cheap trick to save a few cents!

Of course, it's small, affordable and very portable, which I have to say, is the largest reason for its popularity.

The older MkI & II versions have an American made Accutronics 8EB2C1B short triple spring reverb pan which are poor in tone.  MkIII BJrs employ the latter 'Made In Korea' reverb pans, same part number, black finish, but sound more lush and 'hall-like'.

For me, there are better amps on the market designed to overcome the limitations of the BJr and its low quality build.

To quote from elsewhere on this forum "Whichever is best no longer matters. What is adequate to meet regulations, give a useful life and keep them competitive is what does matter... and all that matters!".

Regardless, the main design issue I have with the Blues Junior is it's tendency to oscillation. All three versions of the BJ have this problem, and it really should have been sorted.

The reverb driver circuit is also a poor design choice. A much better circuit could have been implimented at little extra cost (a few cents).

Gagaryn

Yip did the same thing as soon as I got my PRRI, well my second PRRI - the first one cooked itself within a week! That was probably an unrelated problem to be fair.

jpfamps

Gagaryn said:

Yip did the same thing as soon as I got my PRRI, well my second PRRI - the first one cooked itself within a week! That was probably an unrelated problem to be fair.

Actually oscillation could well have been the problem rather than the voltage being too high. 

BJs are prone to oscillating at around 50 kHz (which you can't hear), so although you think your amp is idling, it's actually running at full power!