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Increasing Resistor Wattage


grungehead

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I need a 2W 10K resistor for an amp discharging tool, but the local Radioshack doesn't carry them...

However, they do carry 10K resistors at 1/2 W and 1/4 W and such..

As you can probably tell by now I'm a noob at wiring resistors.. my question is: Can I wire two or more resistors to get 2W 10K?

I did a search on here and google but I think I'm not phrasing it right or somthing because I'm coming up with zilch.

Thanks for you help guys

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You can go four resistors in series 2.5k ohms each at 1/2 watt to get what you want or as the post below said four in parallel at 40k ohms at 1/2 watt each. In series the current through each resistor is the same as the 20k resistor alone but the voltage drop across each one is 1/4 of the source voltage. . The power dissipated across each resistor is

P (power)=E (voltage) x I (current). Each resistor shares part of the total power used in the circuit. In the parallel circuit the Voltage across each resistor is the same but the current through each resistor is 1/4 of the total. It's all good..

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FWIW, I use a 220k 1/2w to discharge tube amp caps. No problems yet. The resistor never gets warm in any way, so to me that says that a 1/2w resistor is fine.

Just DON'T leave it in when you turn on your amp. I've never done it, but I imagine it's a fireworks show. :D

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Wow, thanks alot guys. I opened up my amp today and found out, to my surprise, that is was a solidstate :D

But all is not lost! I found out that my problem was that I had a blown fuse. I replaced the fuse and the amp just blew it up again. I replaced it again and it started smoking and then blew. I'm going to have to buy a new amp and I'm looking at some tube ones.. so this information is really helpful. However, after playing several tube amps and can honestly say I did not see much of a difference between my Crate and the tube heads at GuitarCenter.

No, I'm not here to advertise anything, but I had a Crate G160XL (discontinued) and a Boss equalizer running through the gainstage and I must say it was the crunchy-est, crispiest tone, tightest tone I've heard in a long time. Honestly comparable to the Peavy Joe Satriani signature head.

Thanks Again :D

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You can go four resistors in series 2.5k ohms each at 1/2 watt to get what you want or as the post below said four in parallel at 40k ohms at 1/2 watt each. In series the current through each resistor is the same as the 20k resistor alone but the voltage drop across each one is 1/4 of the source voltage. . The power dissipated across each resistor is

P (power)=E (voltage) x I (current). Each resistor shares part of the total power used in the circuit. In the parallel circuit the Voltage across each resistor is the same but the current through each resistor is 1/4 of the total. It's all good..

( the same as the 20k resistor alone ) that should read 10k resistor.

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Wow, thanks alot guys. I opened up my amp today and found out, to my surprise, that is was a solidstate :D

But all is not lost! I found out that my problem was that I had a blown fuse. I replaced the fuse and the amp just blew it up again. I replaced it again and it started smoking and then blew. I'm going to have to buy a new amp and I'm looking at some tube ones.. so this information is really helpful. However, after playing several tube amps and can honestly say I did not see much of a difference between my Crate and the tube heads at GuitarCenter.

No, I'm not here to advertise anything, but I had a Crate G160XL (discontinued) and a Boss equalizer running through the gainstage and I must say it was the crunchy-est, crispiest tone, tightest tone I've heard in a long time. Honestly comparable to the Peavy Joe Satriani signature head.

Thanks Again :D

I had to chuckle there... B) Tube amps generally have the tubes exposed so they don't melt from their own heat. So if you don't see any tubes... :D

You probably won't hear much difference between tube and solid state hi-gain circuits (in my experience). The reason people play tube amps is because they make beautiful clean to distorted sounds. If you want a tube amp, hunt around on eBay for an old off-brand amp. I definitely wouldn't buy an amp from Guitar Center... you'll pay way too much and get a cheapo product.

Buy vintage man!

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https://www.carvinguitars.com/products/sing...oduct=VINTAGE16

this is about the best deal i have seen on a tube amp either that or weber and turretboards.com both have nice kits

but if you buy a kit i suggest doing some reading and learn a little more about electronics i build a little 5f1 and it about drove me nuts for a couple of days. and to be honest if i had seen that carvin first i would have probably thought about it because its not much more than what i have in that champ and it has a lot more features you know more that a volume knob.

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but if you buy a kit i suggest doing some reading and learn a little more about electronics i build a little 5f1 and it about drove me nuts for a couple of days. and to be honest if i had seen that carvin first i would have probably thought about it because its not much more than what i have in that champ and it has a lot more features you know more that a volume knob.

I bet your Champ sounds better than that Carvin. The Carvin may have a wider range of sounds, but the Champ probably has a better clean tone. (I'm just guessing). See, to sell an amp for $400, you have to use PCB's and cheap components. If you build an amp yourself, you can use whatever components you want to shape the sound.

If you have room, try adding a tone control to your champ. It makes it much easier to balance out the too-brightness of single coils and the muddiness of humbuckers.

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well i have been considering building another encloser for it i found some dynamite boxes that i think would be cool that means building a new chassie if i do that i may do some things too it i have looked at adding another gain stage and making a volume and master with a tone i think i woudl be truely happy with it then.

i will tell ya you it is pretty awsome to hear your own amp even if your lacking in playing ablity like me.

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The tone control will definitely improve your Champ. I'm not sure how useful the master volume will be--that's just a guess, I've never tried it. The Champ only has two gain stages (with loss from pot between them), so I don't know if that will give you the sound you seek from a master-volume amp.

But if you're building a new home for it, leave room and expiriement. :D

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Whoa, that's not even a Champ any more! :D But it looks like a cool amp. It looks like they've tried to reduce the highs and lows so the heavy distortion won't sound muddy and/or spikey. I would definitely use that circuit rather than putting a solid-state pedal in the amp, but to each his own.

Since you have an extra triode, you could use it drive the tone stack with a cathode follower, like the classic Marshall tone stack. You could also wire that extra triode in parallel with the other section of the tube (just connect grid to grid, cathode to cathode, plate to plate). This gives you some extra gain I think but also fattens up the sound. Of course, you don't really need any extra gain with that beast. :D

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