don't buy a Fender Blues Junior .....

General amplifier talk.

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stratman323

Post by stratman323 » Fri Jan 01, 2010 6:11 am

leadguitar_323 wrote:I have a Greco that has "to die for"tone and its pickups are not potted, i have no trouble with squealing as i use my volume control and tone control just like lots of guitarists do , i will never pot these pickups because i don't want any changes in tone and i don't have any problems with squeal as i control it with the controls or a volume pedal
Mick, you are, of course, quite right that non wax-potted humbuckers are period correct for 50s Les Pauls, Tokai are merely copying Gibson. It's not just humbuckers that get microphonic & then squeal, I've had it happen with some Strat & Tele pickups, & it's easily & cheaply cured by wax potting - usually around ?10 per pickup.

What I don't understand is when you say you won't pot the pickups on your Greco in case it changes the tone - why should it? Potting pickups has never changed the sound of any of my pickups & I have never heard of anyone else complain that it changes tone either. Wax potting (when needed) seems to me like one of those rare win/win situations.

And you don't get many of them in life.

:wink:

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Post by leadguitar_323 » Fri Jan 01, 2010 5:59 pm

I googled "wax potting" and read quite a few articles where some said that it takes a bit of top end sparkle from the pickup after wax potting and my Greco is already a very warm sounding guitar so i didn't want to risk taking more highs away. I haven't actually experienced this myself but it made me a bit more cautious..

Mick
so many guitars....so little money...

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Post by ranjam » Fri Jan 01, 2010 9:24 pm

I really believe that is just one more example of the myths and hype that gullible guitar players fall for. I know I'll take a beating for saying that, but I'm used to it. I mean, we live in an age where we thought cloth covered wire sounded 'better'. Complete BS, but come on now; how many of you fell for it? And how many miles of the stuff did AES sell?
I graduated from college in 1979 (am I that old? Yep.) with my degree in electronics technology, and I was lucky that we still did some tube theory, but those new-fangled transistors crept into a lot of my book learnin'. After college I worked a lot in the TV repair business before I got lucky and landed with a few Peavey and Fender repair depots in town. My point here is that I was mentored by a lot of old-timers who were servicing tweed Bassman amplifiers when they were new. Me being gullible, I asked a lot of these same questions, and I always got a smack upside the head with a ''Why would ask something that silly? Don't you know better?' I got to hang around some very brilliant repair men, and they taught me to question a lot of the myths. If you cannot show a formula for why it is so, then it ain't so.
I called Seymour Duncan years ago and asked if I could custom order a PAF or a Seth Lover humbucker and have it potted. Seymour went on to tell me it would change the tone. How? I asked. Will it change the DC resistance of the windings? No. Does it change the inductance? No. Well, how? If you pot just the coil, maybe not at all. If you pot the whole pickup, and pot too much, it can kill harmonics and overtones. So the winding capacitance changes? I don't know, and anyway, the point of a PAF and a Seth Lover is to recreate the original, which was not potted. After that I bought the Gibson '57 Classic pickups (double potted!), and gave up on Seymour Duncan. I don't think my Love Rock with doubled potted humbuckers lacks top end or 'sparkle'.
Any pickup becomes microphonic because the coil is wound too loosely around the pole pieces, and will actually vibrate, where this is coupled to the amplifier. No, it isn't shielding or grounding, it's in the windings themselves, so no amount of lipstick can make the pig attractive. You have to pot it, period. Me being lazy and not having a proper pot and/or wax, I just figure it's more fun to try different pickups, and learn about those. I have tried potting my own pickups in the past, but if you aren't super careful you can melt the bobbin of a humbucker (don't ask how I know :oops:). It's an art, and one I don't feel like learning when pickups are repatively cheap. Single coils are easier, since the vulcanized fiber really won't melt or warp with 'a little' excess heat. Still, trying new pickups is more fun, with less mess.

stratman323

Post by stratman323 » Sat Jan 02, 2010 5:01 am

ranjam wrote: If you cannot show a formula for why it is so, then it ain't so.
Just to muddy the waters a little more here, may I quote an old song title? - It Ain't Necessarily So!

Logically, you're correct. But (and it's a big but...) to follow your logic, all CD players would sound the same, after all it's all merely zeros & ones with digital isn't it? And even getting back to analogue, hi-fi amps of similar or identical spec. should sound the same. But they don't. If you have good ears, if you're in tune with music - and I assume that many of us will have this - there are distinct differences that you can hear. Many of the differences are subtle, many of the differences would not show up on graphs or as part of scientific analysis, but they can be heard.

Why? I have no idea! It's just something that I have found out to be true over the years. So it's quite possible that small changes will make a difference that some people can detect. I accept your point about cloth covered wire, I can't see any reason why it should change the sound. But if you're attempting to make a 50s type pickup it makes sense to make it like the original as far as possible, doesn't it? It was detailed (and badly thought-out) changes that ruined Fenders & Gibsons throughout the 70s.

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Post by JohnA » Sat Jan 02, 2010 8:13 am

I agree cloth coloured wire makes little or no difference to tone, but some things which aren't measureable do. Build an amp with metal film resistors and it'll sound different to building one with carbon composition resistors, use an ohm meter to measure them and there won't be a difference, and it's not just the way they drift over time either, cabon comps sound warmer when they are new.

Capacitors make a difference too, albeit a subtle one, but mallory caps definetely don't sparkle like orange drops.

As for pickups, I've had plenty potted in my time, and could not tell the difference before & after :D

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Post by ranjam » Sat Jan 02, 2010 10:28 am

Metal flim resistors are temperature stable, and carbon unfortunately isn't, even brand new. That's the sound we like, and engineers don't understand. Here's how I measure that; take a simple 100K Plate load resistor in metal film and an old carbon composition type. Measure them, and leave your meter leads clipped to the resistor. If you hold your soldering iron very close to or on the body of the resistor, the metal film stays at 100K, and the carbon composition resistor goes up in value. Now put that resistor in an amplifier that heats up, and the value can fluctuate. The gain goes up and down (very slightly), and the current goes up and down (very slightly). It's a cool 'effect' that makes a cool sound. Not hard to understand, but definately not written in books. I like experimenting with this 'stuff', so I have a basement full of signal generators, decade boxes, and oscilloscopes.
Capacitors make a difference, but not in guitar amplifiers that I can 'see' or measure. The old types can be wound or rolled like a cigarette, and can act as an inductor at high frequencies. That you can measure. But ceramic types aren't wound, and any spec sheet claims they aren't inductive until about 500KHz. I think for low frequency the inductance won't matter, and guitar amplifiers fall into the low frequency catagory. That's why I have never drank from the Kool-Aid that makes me buy a designer capacitor.
Do I have an answer for CD players sounding different? I don't know. Maybe the A/D converters are better in some players. Sure it's just 1's and 0's, but if the buffers and converters are cheaper/better, the CD sounds different. That's the only BS explanation I can come up with on short notice. Amps are easy to explain; different OPT's are a good place to look. Different primary impedance, difference core material, different winding resistance and/or inductance. I don't think anyone sources the same parts. An Ampeg SVT and a US Marshall can both have 6550's and sound completely different. That's not very hard to figure out.
Oh, well. That's enough poop disturbing for one day. If you ever want to open a huge can of worms on any guitar topic, I'm your boy. I have just enough college electronics training and carnival barker experience to make any sane person want to knock me out in ten minutes.

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Post by craigyh77 » Sat Jan 02, 2010 4:46 pm

".....Blues Juniors are Marmite/Vegemite amps - you either love them or hate them. A bit like Texas Special pickups...."

Uh oh stratman!!!! I play my japanese 52 tele with texas specials THROUGH my blues junior! That's like having marmite AND vegemite on the one piece of toast!!!!!

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Post by JohnA » Sat Jan 02, 2010 5:18 pm

craigyh77 wrote: marmite AND vegemite on the one piece of toast!!!!!
That's just wrong!!

stratman323

Post by stratman323 » Sat Jan 02, 2010 5:47 pm

craigyh77 wrote:".....Blues Juniors are Marmite/Vegemite amps - you either love them or hate them. A bit like Texas Special pickups...."

Uh oh stratman!!!! I play my japanese 52 tele with texas specials THROUGH my blues junior! That's like having marmite AND vegemite on the one piece of toast!!!!!
I do like Texas Specials, but only on some guitars. I think they work better with ash bodies, not sure why though. They can sound terrible in some guitars.

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Post by marcusnieman » Sat Jan 02, 2010 6:23 pm

stratman323 wrote: I do like Texas Specials, but only on some guitars. I think they work better with ash bodies, not sure why though. They can sound terrible in some guitars.
I don't like them in Strats but the Tele versions are quite nice. I like the Tex Mex pickups in the Jimmie Vaughan Strat

stratman323

Post by stratman323 » Sun Jan 03, 2010 5:18 am

marcusnieman wrote: I don't like them in Strats but the Tele versions are quite nice. I like the Tex Mex pickups in the Jimmie Vaughan Strat
The Texas Special bridge pickup I have in my US ash-bodied Tele measures 10.2k! That's humbucker territory. But it really fills out the sound of what was a slightly thin sounding guitar before. Great for playing live. Not the most subtle pickup I've ever heard though.

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Post by blake375 » Mon Jan 04, 2010 2:42 am

After declaring my love for the Blues Junior not long ago, I have to make a concession: I've always played strats or p90-equipped guitars through it. This weekend I played a LP through it and it sounded terrible. Playing on only the plain strings sounded okay, but the wound strings just sounded like farts. Especially the E. Not a problem with the guitar either - sounds amazing through my Boogie. I was amazed - it sounded like a different amp: a really awful one!

stratman323

Post by stratman323 » Mon Jan 04, 2010 5:02 am

:lol:

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Post by marcusnieman » Mon Jan 04, 2010 6:32 am

blake375 wrote:After declaring my love for the Blues Junior not long ago, I have to make a concession: I've always played strats or p90-equipped guitars through it. This weekend I played a LP through it and it sounded terrible. Playing on only the plain strings sounded okay, but the wound strings just sounded like farts. Especially the E. Not a problem with the guitar either - sounds amazing through my Boogie. I was amazed - it sounded like a different amp: a really awful one!

Fender for a Fender - last gig of 2009. Still love my Juniors:

Image

stratman323

Post by stratman323 » Mon Jan 04, 2010 6:49 am

Spot the Grolsch washer. :wink:

:D

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