Fender musicmaster bass amp mods update#
Fender musicmaster bass amp mods series#

I'm a fan of the Mojo Dijon caps myself, they sound not too unlike a good old Fender blue Ajax cap. 0047 is merely rolling off highs to ground so it's not so critical there which is why I reused that one. I probably didn't use it cause I don't like that particular brand of cap that Fender was using at the time. I have had mystery issues be something as minor as this. Oh, and now that I'm thinking about it, do check your pots as well, hit them with good quality De-oxit contact cleaner. Chances are it's good but you never know. 01 connected to the anode of the 12ax7 (either pin 1 or 6). But like I said, if this is a recent phenomenon I would check your signal cap, the. If you have a look at a Musicmaster Bass Amp schematic and a Deluxe 5E3 first thing to notice is the cap values. The tone stack in these does tend to roll a lot more highs off than your typical Fender amp. If it's a recent problem the first thing I check is your preamp tube, next would be your signal caps. With regards to the tone control sounding funny, I'm assuming you are using this for a guitar amp?Īnd the problem just developed or was it odd in the first place? And yes, these do sound good stock and I'm a fan of the CTS speaker. I don't bother with the Variac, no need really.

Fender musicmaster bass amp mods update#

No biasing required.Īh! Thanks for the correction! I'll update it. And, you can just buy a pair of tubes and drop them in. The later ones used 6V6 tubes, I think these sound more English than a 6V6 model. These amps can be a real treat for those on a budget or those who just like a wonderful tone!Īnother nice thing about these is they use the rather easy to find 6AQ5 tube. Great amp for a jazz player who doesn't need fusion volume.

Fender musicmaster bass amp mods series#

The customer will be replacing the speaker, I would go with a Weber English series or a real Celestion. Think 18 Watt Marshall with a $300 pricetag. Jangly top end with that nice euphonic mid. If I drop a new one in there this either sits around my tiny space or becomes sea turtle food eventually. I could sell the customer a new cap here but why? This one is perfectly good and I'm a reduce reuse recycle kind of guy. If that doesn't work, I'll give the shielded wire a shot.I'm using a 250pf cap for the highs and if you notice, I'm re-using that. When my extra wire arrives, I'll try using a longer length and routing it out towards the input jacks and around the board. So at least I've localized the issue a little more.Īs it is in the above photo yields the quietest results.Īs far away as possible from those transformer wires is definitely the trick. The volume of the hum is now controlled pretty much exclusively by that wire from the volume pot going to the preamp tube. The way the transformer wires are now, they don't affect the volume of the hum when moved, jiggled, prodded. May have lessened a little bit, but not near enough to say its fixed. Hum is still there with this configuration. I snipped that sucker literally seconds after taking the above photos.įuse holder and 1amp slo-blo are on the way along with a few lengths of wire.Īlso slightly rerouted the wire that went from the preamp tube to the volume pot. Not looking for dead silence with this thing, but would like to be able to put a mic in front of it. My first guess was a cold solder joint where the group of transformer wires meet the board, but after moving those wires around some, it seems that its their location relative the the things around them that are most culprit.Īnyone here able to tell me what might be going on here?Īnd of course, what the simple fix is. So at least I've found the area that seems to be creating the bulk of the problem, however, I don't know if the hum is going away because the wire is being pushed against the caps, or because its being pushed away from the volume pot. I was able to wedge the group of wires behind a small bolt in the chassis to hold it in place this way. If I push the wires away from the volume pot and up against the two big caps on the board, the volume of the hum drops considerably. Should be noted as well that the wires are also close to the volume pot just before they attach to the board. When those three wires are floating in the space between the transformer and board/caps, the hum is at its loudest. All looked clean and tight, but was able to pinpoint at least a good portion of the hum cause to the three wires going from the transformer to the board. Pulled the chassis to investigate the hum hoping to see something obvious. The amp has had a recent recap along with a tone stack mod. Loud enough that I call it more of a buzz than a hum. Just received a 6v6 version Musicmaster Bass Amp.