Blue blob caps in Silverface Fenders?

[bob p]

Chuck, I'm like you in that I try to find the best speaker for a particular build, and I keep a pile of speakers on-hand to do that. I hate speaker rolling, but I really hate speaker break-in. I can't stand the idea of waiting through 2 years of playing with cone cry to break in a speaker. To me, I wouldn't care how good it sounds when I finally get to 2 years of break-in, I just don't can't put up with the problem for 2 years while I wait for it to go away.

Do you have any idea how many hours your 2 years of intermittent playing / break in period actually provides?

When I have to do speaker break-in I mount the speaker in a cab, place it in a closet at the far end of the house with comforters thrown over it and I drive it with high volume thumpy signal for a week. (168 hours of RHCP, AC/DC, LZ on a CD changer.)

It's a PITA, but my experience has been that 24 hours isn't enough and that a solid week puts me at the point of diminishing returns, and is about as good as anything longer. I absolutely hate doing it. I wish I had a place where I could do this without having to listen to it. I should probably build a bona-fide isolation box.

I talked to Dave at Avatar about break-in a couple of times. He buys his private label speakers from Celestion and he runs them all through a forced break-in. He breaks in large numbers of speakers at the same time, running signal through them in a warehouse. IIRC he told me that he breaks them in at night on a variac when nobody is there, though I can't remember for sure, it was a long time ago. I can't imagine that they get a long break-in, given that his speaker sales are probably brisk enough to make prolonged break-in impractical.

It's interesting that Avatar goes through the trouble of breaking in their Chinese Celestion private label speakers. I'm wondering if they do this just to be able to say that they are selling broken-in speakers, or if he's hearing the same types of artifacts in his private label speakers that you're hearing.

[TimmyP1955]

Depending on the form factor required, I use these for repairs:

http://www.mouser.com/search/Product...2d150103J630BB

http://www.mouser.com/search/Product...%2d368%2d55103

http://www.mouser.com/search/Product...dECW%2dF6823HL

http://www.mouser.com/search/Product...r=1431%2d6102K

[g1]

it sounds like they changed the color to Mojo Orange.

I think plasti-dip of signal caps would add a lot of mojo to builds. Many colours available.
Add origin story to taste.

[Chuck H]

Chuck, I'm like you in that I try to find the best speaker for a particular build, and I keep a pile of speakers on-hand to do that. I hate speaker rolling, but I really hate speaker break-in. I can't stand the idea of waiting through 2 years of playing with cone cry to break in a speaker. To me, I wouldn't care how good it sounds when I finally get to 2 years of break-in, I just don't can't put up with the problem for 2 years while I wait for it to go away.

Do you have any idea how many hours your 2 years of intermittent playing / break in period actually provides?

When I have to do speaker break-in I mount the speaker in a cab, place it in a closet at the far end of the house with comforters thrown over it and I drive it with high volume thumpy signal for a week. (168 hours of RHCP, AC/DC, LZ on a CD changer.)

It's a PITA, but my experience has been that 24 hours isn't enough and that a solid week puts me at the point of diminishing returns, and is about as good as anything longer. I absolutely hate doing it. I wish I had a place where I could do this without having to listen to it. I should probably build a bona-fide isolation box.

I talked to Dave at Avatar about break-in a couple of times. He buys his private label speakers from Celestion and he runs them all through a forced break-in. He breaks in large numbers of speakers at the same time, running signal through them in a warehouse. IIRC he told me that he breaks them in at night on a variac when nobody is there, though I can't remember for sure, it was a long time ago. I can't imagine that they get a long break-in, given that his speaker sales are probably brisk enough to make prolonged break-in impractical.

It's interesting that Avatar goes through the trouble of breaking in their Chinese Celestion private label speakers. I'm wondering if they do this just to be able to say that they are selling broken-in speakers, or if he's hearing the same types of artifacts in his private label speakers that you're hearing.

I've often wondered what difference it makes breaking in a speaker with programmed music or straight AC as opposed to actual playing. I would think it makes some difference. Perhaps not noteworthy.

I'll guess I had about 200 hours on that particular speaker for break in. But that's using a 15W amp (usually cranked up clipping and making closer to 20W?). The cone cry disappeared some months later with less playing time in those months. So perhaps less than the two years stated. I like this speaker with this amp well enough that I would do it again if I had to. The only other speaker I liked with this amp was the Eminence Cannabis Rex. That speaker sounded great out of the box, but sounded too dull and boxy once it started breaking in. If you like the "Celestion" sound, but would prefer it a little less brash then the Cannabis Rex is your huckleberry Nicely efficient too, which is nice and pretty much a criteria for me. Lower efficiency speakers NEVER "feel" good to me. Though I've heard many that seem to sound just fine recorded. Al the best tones from vintage Fenders and such that were almost certainly stock and had old Jensens or Oxfords. If THAT is a tone you like it's also worth looking into acquiring some vintage 12" full range Magnavox speakers. Similar in efficiency to the Oxfords and a nice tone reminiscent of other speakers of the era.

But, indeed, you just never know how it will be for a certain amp. I tried a pair of Eminence Private Jacks in the above mentioned 2x12 cab and HATED them. Good bass, good low mids but only a little very high treble, but they seemed to lack a useful upper mid and treble voice. Then a friend with a Peavey Classic 50 asked me what to do about the crappy tone he had I changed out the generic, square magnet turds that were in there for the Private Jacks and the amp instantly sounded great on all settings!!! The exact right speaker for THAT amp as it happens (make a note of it). I'd happily play it at a gig. It was that much improved with only a speaker change. That, for me, was very strong testimony that having the right speaker for a given amp can be critical, if not key to it's overall feel and tone. Those PJ's were a very wrong speaker for one amp, yet perfect for a different one.

[Leo_Gnardo]

Depending on the form factor required, I use these for repairs:

Thanks for those links! First one shows Mallory 150 are still available, you have to search for them as Cornell Dubilier now that they bought Mallory some years ago. Third link shows us some Xicon parts are still available. Xicon was Mouser's house brand, perfectly good parts, but AFAIK Mouser has discontinued the line. Whatever's still in stock is offered for sale. Some enterprising salesman should grab 'em all, because parts with some obsolete brand on them (Vitamin Q for instance) are always better than whatever is being manufactured today, so goes the legend, right? You & I know different but somebody can always sell pixie dust to the believers for a profit.

[bob p]

speaker break-in

I've often wondered what difference it makes breaking in a speaker with programmed music or straight AC as opposed to actual playing. I would think it makes some difference. Perhaps not noteworthy.

I don't use AC for prolonged periods because I just can't stand to listen to it. Same for an amplified sweep generator. Or a random band pink noise generator -- that's probably the best way to do it, but I just can't stand to listen to it, so I use music. It seems to work good enough.

I tried to choose music that would suit a particular need, while still being good enough to be tolerable. I liked using the RHCP CDs to loosen up the suspension with good thumpy bass excursions, though just about any dance music would do. I ended up picking Back in Black just because it was in the shop. To try to approximate live guitar I use the Led Zeppelin BBC Sessions CD, which is about as close to a live guitar sound as I have handy. Guys with studios who really want to do this right would probably record their guitar signal and then reamp it into the cab. Or maybe use a looper pedal since those are so common now. I'm not that fancy. I just use an old CD player and amp that I had in my garage.

[Randall]

Interestingly the Mallory 150s are close to twice the cost at Mouser than they are at CE Dist. Shipping is less at Mouser, tho.

[Tom Phillips]

Interestingly the Mallory 150s are close to twice the cost at Mouser than they are at CE Dist. Shipping is less at Mouser, tho.

I noticed that too. However, as I recall, Mouser stocks the 5% tolerance Mallory 150's and does not offer the 10% tolerance line which is what CD Dist carries. Not that 5% vs. 10% makes a significant difference for guitar amp work but it's probably a factor in the price difference.
T

[Chuck H]

I seem to recall that the 150's use to be plain polyester and foil caps. Now they're "metalized". If I'm not mistaken, metalized is when an aqueous metal solution is applied to the dielectric. It is somehow imbued with properties that allow it to self heal in the event that over voltage punches holes in the film (good), but still different in construction from the old school polyester and foil caps (bad?). My point is just that IF this is the case, and I think it is, the 150's got their rep when they were:

1) Made like the old school caps, and
2) Also happened to be axial lead

Making them perfect candidates for vintage restorations. Not so now that they are made with the same metalized construction as most other film caps. But the rep seems to live on because, oddly, no one has ever addressed this.

[Justin Thomas]

Making them perfect candidates for vintage restorations. Not so now that they are made with the same metalized construction as most other film caps. But the rep seems to live on because, oddly, no one has ever addressed this.

Or, nobody ever noticed a change in the sound. Of course, now that you mention it, everyone will suddenly notice and say how bad the Mallory 150s are, and then the booteek cap prices will get even higher...

Dammit, Chuck!

Justin

[Enzo]

Hmmm. When I read "metalized" my image is that instead of a separate foil strip and a plastic strip wound together, they apply a metal coating to the poly strip so it is one piece to wind up. Don't know why water would be involved.

[Leo_Gnardo]

I seem to recall that the 150's use to be plain polyester and foil caps. Now they're "metalized". If I'm not mistaken, metalized is when an aqueous metal solution is applied to the dielectric. It is somehow imbued with properties that allow it to self heal in the event that over voltage punches holes in the film (good), but still different in construction from the old school polyester and foil caps (bad?). My point is just that IF this is the case, and I think it is, the 150's got their rep when they were:

1) Made like the old school caps, and
2) Also happened to be axial lead

Making them perfect candidates for vintage restorations. Not so now that they are made with the same metalized construction as most other film caps. But the rep seems to live on because, oddly, no one has ever addressed this.

Let the vintage police complain all they want, I still use Mallory 150, my crustomers and I are perfectly satisfied with their tone and reliability. IF there's a factor in the "tone" I expect it has more to do with the dielectric (insulating) layer. For those who must have non-metallized, I dunno maybe Mojo's "Dijon" or Sozo or Jupiter will satisfy them. Going in the other direction expense-wise the Panasonics and what's left of the Xicons also work perfectly well. As it's been said, there may be a placebo effect - if the crustomer demands boo-teek $$$$ parts, source 'em, sell 'em, charge labor & a markup, smile on your way to the bank.

[Chuck H]

Hmmm. When I read "metalized" my image is that instead of a separate foil strip and a plastic strip wound together, they apply a metal coating to the poly strip so it is one piece to wind up. Don't know why water would be involved.

Your right. It's a paint the film sort of thing, but not water based. Most of the new agents for cleaning are water based now. My bad. The idea is the same though, different paint solvent is all.

[Chuck H]

Let the vintage police complain all they want, I still use Mallory 150, my crustomers and I are perfectly satisfied with their tone and reliability. IF there's a factor in the "tone" I expect it has more to do with the dielectric (insulating) layer. For those who must have non-metallized, I dunno maybe Mojo's "Dijon" or Sozo or Jupiter will satisfy them. Going in the other direction expense-wise the Panasonics and what's left of the Xicons also work perfectly well. As it's been said, there may be a placebo effect - if the crustomer demands boo-teek $$$$ parts, source 'em, sell 'em, charge labor & a markup, smile on your way to the bank.

I had my bacon saved by "metalized" cap construction at the 2009 NAMM show! The amps I was presenting there used a Zobel filter across the OT primary and I used the 600V caps I had on hand. I didn't know at that time just how high the voltage differential there was with the voltage spikes this circuit was specifically intended to manage. About two weeks later the demo amp started showing signs that the cap was shorting. It just couldn't heal itself anymore. The metalized self healing property kept it alive for a time where a standard foil might not have.

[Tom Phillips]

Regarding the blue blob caps discussed in the original post. My take is that users often freak out when they see something that stands out as "different" or "changed" from the established build of the time. I think this is heavily influenced by their quest for some magic change they can make to convert their amp to a magic tone machine. In reality, I don't think there is anything inherently bad about the "blue blob" caps. I call them "Blue drops" since they are similar shape to the Sprague orange drops. Similarly people say that the brown caps that showed up in the late 60's sounded like crap but I have never heard the proof. My theory is that they look like crap AND they showed up in the Fender amps when the popular opinion was that the overall sound performance was taking a turn for the worse. However, I don't think it was those specific caps that were the cause of the problem. Just my opinion and I acknowledge the fact that the debate about the sound of various types of capacitors will never end.