32 Ohm
P1 = R * I^2
8 Ohm
P2 = 1/4 * R * (2*I)^2
P2 = 1/4 * R * 4 * I^2
P2 = R * I^2
P1 = P2
I know this wasn't asked, but it has something to do with Ohm's law
Good luck
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Engineers & Gurus- I'm rewiring a 6x10, double check my math?
- Thread starter McNothing
- Start date
32 Ohm
P1 = R * I^2
8 Ohm
P2 = 1/4 * R * (2*I)^2
P2 = 1/4 * R * 4 * I^2
P2 = R * I^2
P1 = P2
I know this wasn't asked, but it has something to do with Ohm's law
Good luck
I hadn't done the calculations but that looked a little sus to me as well.
Doesn't change the fact that there are major potential physical problems with this.
- Feb 12, 2006
- 61,072
- 5
- 221,142
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Nope, the math is correct and highlights the other problem I alluded to. It also is derived from Ohm's law
Nope, the math is correct and highlights the other problem I alluded to. It also is derived from Ohm's law
Sorry, bad writing. I wasn't saying that the math looked sus, but that the math being wrong looked sus to me.
Not sure what you are saying with the other problem? The only other that I think you mentioned was Speaker polarity.
One or the other. Scientific requires specifically Academic calculation. The two go hand-in-hand. Essentially, they are the same.
Where, and when, will you be using this rig...? In this modern age, can you not work with simply a 2x10/2x12 or a 4x10? If you play a gig that requires a 6x10... who, apart from you and the band, are going to hear it...?
If the 6x10 is exactly half the size of the correctly sized bass 6x10 then you should be able to chop off the top 2 speakers block off the second 2 and install the third 2.
Of course, that ends up giving you a 16ohm cabinet that is absolutely useless for your purposes.
Could you build a second matching cabinet for a 2 2x10 stack?
If you are going to go that far leave the current cabinet as is and make new 2 2x10's or a single new 4x10.
Or, leave the two mismatched speakers in the holes, but not connected, to serve as passive radiators.
Changes the effective volume and porting of the box, and the passive radiators will breath in the opposite direction of the main speakers.
Passive radiators are a bass reflex option and are more than two unconnected speakers. This could lead to destruction from over-excursion, just like speakers played in free air.
- Feb 12, 2006
- 61,072
- 5
- 221,142
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Really bad idea (or is this a joke?). The area, compliance and mass of the passive radiators combine with the air mass in the box and the driver to create a tuned system. 2 unconnected drivers are goigto fall WAY outside anything even remotely reasonable.
Ok, since my math wasn't being challenged I wired up the speakers and played some music.
I'll describe the results for posterity. If you want a 6x10 with the original (killer sounding) CTS 32 ohm speakers, adding two 8 ohm speakers to the mix is a good way to get closer to a 4ohm load for use with an SVT. I haven't found a modern speaker that approaches the sound of the originals, hence the fools errand. I've always been a fan of mixing speakers in AC30s and other 2x12s for guitar as well.
I would stop there for purposes of my original post, but since everyone seems interested in all the real (or imagined) secondary concerns, more details:
It sounds great with my SVT- ran it for a few hours at practice the past two nights with no issues. I am mic'd on stage so cab volume is low. I push the amp hard, with a potentiometer in the effects loop and both pre/power stages past 9pm to I get the clipping I like. I also pad the signal right before input with a compressor. The amp setup is well vetted on a couple long tours (w/ a 70s 810E).
The impetus for this experiment was that the SUNN speakers break up nicely and travel nicely, but have a top-heavy frequency range. Too much Chris Squire. They are being pushed harder now with the SVT speakers in circuit, and the resulting crunch gets me something of an exaggerated Ampeg growl. Its excellent for my style and allows me to back off the pre-gain. The four SVT speakers on the bottom blend in smoothly and seem to be under-stressed (a visual comparison of travel), probably no speaker clipping there. Each SVT speaker has the characteristic 810E sound close up, but the overall cab is more aggressively tuned than an 810E and MUCH less loud at a given output (good for my purposes).
*NOTE* All speakers are CTS from an era where application-specific voicing was less exaggerated. Identical magnets with slight differences in cone and coil. The PA version of this cab is the same enclosure, so I knew the cab was engineered to handle more bass that I was subjecting it to. A success for me but keep in mind: SEALED cab, mild speaker voicings, and low stage volume. I can fit the entire rig in my Corvair and lift the cab on stage alone. Selling the 810E and not looking back.
I'll describe the results for posterity. If you want a 6x10 with the original (killer sounding) CTS 32 ohm speakers, adding two 8 ohm speakers to the mix is a good way to get closer to a 4ohm load for use with an SVT. I haven't found a modern speaker that approaches the sound of the originals, hence the fools errand. I've always been a fan of mixing speakers in AC30s and other 2x12s for guitar as well.
I would stop there for purposes of my original post, but since everyone seems interested in all the real (or imagined) secondary concerns, more details:
It sounds great with my SVT- ran it for a few hours at practice the past two nights with no issues. I am mic'd on stage so cab volume is low. I push the amp hard, with a potentiometer in the effects loop and both pre/power stages past 9pm to I get the clipping I like. I also pad the signal right before input with a compressor. The amp setup is well vetted on a couple long tours (w/ a 70s 810E).
The impetus for this experiment was that the SUNN speakers break up nicely and travel nicely, but have a top-heavy frequency range. Too much Chris Squire. They are being pushed harder now with the SVT speakers in circuit, and the resulting crunch gets me something of an exaggerated Ampeg growl. Its excellent for my style and allows me to back off the pre-gain. The four SVT speakers on the bottom blend in smoothly and seem to be under-stressed (a visual comparison of travel), probably no speaker clipping there. Each SVT speaker has the characteristic 810E sound close up, but the overall cab is more aggressively tuned than an 810E and MUCH less loud at a given output (good for my purposes).
*NOTE* All speakers are CTS from an era where application-specific voicing was less exaggerated. Identical magnets with slight differences in cone and coil. The PA version of this cab is the same enclosure, so I knew the cab was engineered to handle more bass that I was subjecting it to. A success for me but keep in mind: SEALED cab, mild speaker voicings, and low stage volume. I can fit the entire rig in my Corvair and lift the cab on stage alone. Selling the 810E and not looking back.
