TAD Bipolar cap, Mojo

[tmac]

Just got a new Mojo catalog and inside they're touting the TAD "bipolar" 25uf/25V cap as "a major upgrade for cathode bypass".

Anybody tried these puppys? Are they new? Are they a major upgrade in the tone department?:confused:

I thought bipolar meant a bit unstable :eek: :crazy

[DanD]

[quote=tmac;2516616]Just got a new Mojo catalog and inside they're touting the TAD "bipolar" 25uf/25V cap as "a major upgrade for cathode bypass".

Anybody tried these puppys? Are they new? Are they a major upgrade in the tone department?:confused:

I thought bipolar meant a bit unstable :eek: :crazy[/quote

Polarity: Capacitors that may be safely operated with only one
DC polarity are called "polar" Capacitors which can be operated
without regard to polarity are "non-polar". Sometimes "polar"
caps are combined in special ways to allow a limited ability to
cope with revering polarity are called "bipolar"

Hope this helps.
DanD

[tmac]

Well thanks DanD and sorry for the confusion but I really wasn't looking for a definition of polarity. That was my attempt at lame humor! (Sorry if I offended anyone with that)

So to clarify: I'm looking for what makes these particular TAD caps a "major upgrade" and if anyone is using these caps & how they like 'em (and why)?

http://www.mojomusicalsupply.com/item.asp?pid=60105&pg=44974&id=5166156

[Giraffecaster]

if it's brand new i don't think anyone's had a chance to try it. why don't you be the first and report back?

[tmac]

if it's brand new i don't think anyone's had a chance to try it. why don't you be the first and report back?

OK.:munch

[mr coffee]

but they are BIG.. bi polar in these mean they swing both ways...:jo
there is no positive/negative

[hasserl]

I didn't realize there was a problem with polar caps in cathode bypass apps. Maybe this is a case of a cure for an ailment that doesn't exist.

[willsmusik]

I have used these in several repairs. A 66 Deluxe Reverb. My 1970 Princeton Reverb, a 64 Princeton non reverb and am getting ready to install in a 66 Tremolux and a Bassman 100. So far as i can tell they are going to work great. I am thinking they may be made by F&T from Germany and I also use F&T 100uf/100v in the bias supplies of these amps. Without exeption these projects sound wonderful now. I wouldn't hesitate to use them all the time.

[tmac]

Thanks for the info guys. One reason I was curious about these was because I had a tone issue with my rebuilt '69 Super Reverb - the 'verb channel just sounded "off", kinda harsh without the right overtones, just not pleasant and I couldn't figure out what the heck was going on. The normal channel sounded right but the verb channel didn't. After changing around a bunch of things I finally swapped the cathode RK/CK around on othe channels and boom, now the normal channel sounded like crap. They both have identical new Sprague 25uf/25V caps and 1.5K carbon comps that measure exactly the same. I just think that cap had an issue which I believe is unusual I think since the Sprague's are well respected. Guess I should get a meter that will test caps.

BTW, this SR was real mess when I got it, it had been "modded" and had the really bad rats nest early CBS wiring. Good thing I got it cheap 'cause I've spent a lot of time and $ getting it rebuilt. :crazyguy

[Giraffecaster]

the bi-polars are 1.50 and 2.25 for the 50v. for 7.50 you can try all 4!

[scottl]

http://www.mojomusicalsupply.com/images/5166156.jpg

[donnyjaguar]

Its pretty obviously a pair of polarized electrolytics stuck back-to-back. When it comes to designing hi-fi speaker crossovers this is generally considered the worst way to do it - although it does work okay. Given there's no current reversal in a bypass capacitor I submit using a bipolar is a waste of time (and money). If you want to be a pedant, you can factor in the ESR of this type of capacitor will be twice that of a regular 'lytic and this is generally considered a bad thing. Also consider that a these types of cap's really need a current reversal to work properly (like you'd find in a speaker crossover cct). I think you'll find there's some clever marketing at play here. :)