1/4 jack power rating?

Electricblue · #1 05-03-2011, 11:01 AM

After making so many stupid threads about stupid cab/amp ideas, I actually bought a rig second hand.

Ashdown MAG300/MAG410/MAG115.

Is it worth replacing the plastic jacks on the back of the cabs with metal ones?

I would use the speakon ones, but I would have to use 1/4 into the head anyway, so I would be at no advantage, I got some massively beefy cables with the stack anyway.

I was thinking of daisy chaining my cabs in parallel, since my second cable doesnt quite reach the bottom cab, forcing me to run the cabs side-by-side.

It puts me off, the idea of 500w max going through weedy little plastic jacks like these:

Thoughts?

spaz21387 · #2 05-03-2011, 11:03 AM

I really doubt it matters if the stock one is having problems that's the time to replace

Electricblue · #3 05-03-2011, 11:16 AM

No problems, but I havent tried daisy chaining the cabs yet, and I would hate for 500w to go through those jacks...

john m · #4 05-03-2011, 11:31 AM

I usually use metal jacks when shielding is an issue.

The current going to the speaker is high, but not constant.

Speakons are the best because there is more surface area at the connection point.

**JdoubleH** · #5 05-03-2011, 11:37 AM

You'll never come close to passing enough voltage or current through the jack to exceed the physical limits of the contacts or insulators.

That said, I once had a Trace Elliott amp that seemed to have one if these plastic-body jacks fail every time I gigged with it. The problem wasn't too much power, but brittle plastic. Being a resourceful chap, I carried a bag of spares and a soldering iron with me wherever I took it.

Eventually I had all of them replaced, but it I say use the strongest jacks available. You can easily make a speakon to 1/4" cable without soldering from one of your existing cables. speakon's are really easy to work with. Ready made speakon/ 1/4 cables are available too. Best bet? Combo speakon / 1/4 jacks; Use either type of cable.

Bassamatic · #6 05-03-2011, 11:46 AM

There are no shielding issues with speaker connections. The impedance is nearly 0 and the voltage is high.

Metal jacks are always best for durability. Just get the Switchcraft basic jacks - not even the type shown in your photo.

Consider using speakons and making the proper cable to connect to your amp. Better current handling and less chance of someone using a guitar cord there and blowing up your amp.

Bassamatic · #7 05-03-2011, 11:48 AM

If not the Speakon, Use the 2 conductor version of this one.

Electricblue · #8 05-03-2011, 11:53 AM

Fair enough guys, I will try invest in some speakons when I can get some funds together.

For now, will there be any issues with running a jack cable from the head to my 410, and another from my 410 to my 115? Are the jacks in the back of my Ashdown head in direct parallel?

Bass_Pounder · #9 05-03-2011, 12:07 PM

After all the info provided in previous threads, you actually went with a 1X15 and 4X10 ?

BassmanPaul · #10 05-03-2011, 12:47 PM

Quote:

Originally Posted by JdoubleH

You'll never come close to passing enough voltage or current through the jack to exceed the physical limits of the contacts or insulators.

.

Sorry Bro. but yes you will. the phone plug was originally designed for use in the telephone industry thus "phone". Its service was 48V DC at a couple of hundred milliamps.

As for the jack pictured I have seen them melt under heavy load from a powerful amp.

As regards voltage, many of the more powerful amps put out enough voltage to cause you harm especially if being used with an amp in bridge.

Any amp with more than a couple of hundred watts output should not be using phone plugs.

john m · #11 05-03-2011, 01:00 PM

Insulation is not an issue. Contact size is, due to current.

Lots of current is supplied to a speaker-especially in the lower frequencies (that's why speaker wire is so fat). Voltage to the speaker is limited by the rails in the amps power supply. Usually around 30 Volts.

Electricblue · #12 05-03-2011, 01:02 PM

Quote:

Originally Posted by Bass_Pounder

After all the info provided in previous threads, you actually went with a 1X15 and 4X10 ?

It was cheap. If I had the choice, I would have gone for 2 matching 410's but there we go.

You sound dissapointed?

BassmanPaul · #13 05-03-2011, 01:06 PM

Quote:

Originally Posted by john m

Insulation is not an issue. Contact size is, due to current.

Lots of current is supplied to a speaker-especially in the lower frequencies (that's why speaker wire is so fat). Voltage to the speaker is limited by the rails in the amps power supply. Usually around 30 Volts.

Again I'm sorry but I have to correct something. Most SS amps use a positive and negative supply. Using your 30V, even 30V each side will give you less than 100W or so into 8Ω. When you get into the 1000W range you looking at more than a 100V per side.

SurferJoe46 · #14 05-03-2011, 01:41 PM

I was told that the plastic was a better choice for when someone was installing or taking out a jack and the amp was on, as the plastic wasn't grounded and it wouldn't cause a dead short or a lot of noise when the male exited the female part.

Electricblue · #15 05-03-2011, 02:09 PM

Quote:

Originally Posted by SurferJoe46

I was told that the plastic was a better choice for when someone was installing or taking out a jack and the amp was on, as the plastic wasn't grounded and it wouldn't cause a dead short or a lot of noise when the male exited the female part.

I experience that a lot

Also, I think it does short for a brief moment.

DWBass · #16 05-03-2011, 02:11 PM

Amps with these types of jacks have been in use for years. I've never had an issue and I had a Yorkville XS800 pumping 800w. I wouldn't worry about it.

BassmanPaul · #17 05-03-2011, 02:16 PM

Quote:

Originally Posted by SurferJoe46

I was told that the plastic was a better choice for when someone was installing or taking out a jack and the amp was on, as the plastic wasn't grounded and it wouldn't cause a dead short or a lot of noise when the male exited the female part.

Even the plastic ones will short the tip to the sleeve of the plug as it is inserted.

Selta · #18 05-03-2011, 02:16 PM

Quote:

Originally Posted by Electricblue

Fair enough guys, I will try invest in some speakons when I can get some funds together.

For now, will there be any issues with running a jack cable from the head to my 410, and another from my 410 to my 115? Are the jacks in the back of my Ashdown head in direct parallel?

Other than sounding like crap, no. (I used to use those exact same cabs. They don't gel together well at all). Jacks on the head are in parallel...

Electricblue · #19 05-03-2011, 02:23 PM

Quote:

Originally Posted by Ray Salamon

Other than sounding like crap, no. (I used to use those exact same cabs. They don't gel together well at all). Jacks on the head are in parallel...

To my ears, they sound superb together. Were yours the old UK-made ones with the blue speakers, or the new chinese ones?

BassmanPaul · #20 05-03-2011, 02:24 PM

Quote:

Originally Posted by Electricblue

You sound dissapointed?

When a question is asked and the poster is given good advice it is disappointing when he or she ignores that advice. It negates all the typing and time that goes into posting.

The mere fact that it was cheap doesn't make the pairing any better! The 15 will always be a weak link in your system. I hope at least you stack the 15 on top of the 4x10 so you can hear its cries for mercy.