I have an old (vintage probably) speaker cabinet. It has 2 woofers and one tweeter. It is is all wired very simply with two 1/4 inch jacks going directing to one speaker and then wires going from that to the other one. The tweeter seems to have a resister of some kind in it's wire. The backs says "input= 65 watts" How should I test this? Do I need to buy a 65 watt amp?
It didn't work when I plugged a stereo amp into it turned all the way up, but then again I did use cable that I made by cutting the end off of one end and put it into the amp. It did make a very quite hissing noise when I did that. The output from the head phone jacks on a 15watt guitar amp did not work either. Does the amp need to be close to 65 watts in order to work?
No, as Richie said any amp will work. Do you have a multi-tester? If so, check the continuity or DC resistance of the speaker circuit. It should be between 3 and 15 ohms.
That resistor thingie on the tweeter is called a capacitor. It protects the tweeter from low frequencies.
If you had a slight hiss, it sounds like the speaker may be OK and that no sound is getting to them from the amp?
That resistor thingie on the tweeter is called a capacitor. It protects the tweeter from low frequencies.
If you had a slight hiss, it sounds like the speaker may be OK and that no sound is getting to them from the amp?
Well I'm saving up (selling all my crap) to get a decent power amp. This will be used for bass guitar, electric guitar, and vocals. I'm shooting for the 50 to 100 watt range as I think this will be loud enough. I'm waiting for a book that I ordered form the library to arrive that is on the subject of building speaker systems, but I couldn't resist asking another question. What impedance should I look for in buying the amp? If the speakers that I have don't match it, I will buy 10 inch ones that do match the amp(I want to use the same cab as the amp will use up most of my funds). What is the most common impedance for guitar playing? Sorry if this question is dumb or out of place. I 'm not quite sure about this stuff yet.
Hi,
buy 8ohm drivers.
If you use a pair in the cabinet, you can either run them in parallel or use an amp to drive each.
Your power amp must be capable of driving a 4ohm reactive load, which is much worse than driving a 2ohm resistor.
Be careful if the spec just shows power into 4r0. That alone does not guarantee suitability for 4ohm speakers (8//8).
buy 8ohm drivers.
If you use a pair in the cabinet, you can either run them in parallel or use an amp to drive each.
Your power amp must be capable of driving a 4ohm reactive load, which is much worse than driving a 2ohm resistor.
Be careful if the spec just shows power into 4r0. That alone does not guarantee suitability for 4ohm speakers (8//8).
Hi,
the treble driver should be integrated via a crossover, it should not be in parallel.
The crossover has the effect of driving EITHER the bass/mid OR the treble, not both together, except at the crossover frequency. At the crossover frequency the reactive components raise the apparent impedance of the low pass leg and the high pass leg and so the overall impedance is roughly equal to the nominal impedance of the speaker.
the treble driver should be integrated via a crossover, it should not be in parallel.
The crossover has the effect of driving EITHER the bass/mid OR the treble, not both together, except at the crossover frequency. At the crossover frequency the reactive components raise the apparent impedance of the low pass leg and the high pass leg and so the overall impedance is roughly equal to the nominal impedance of the speaker.
Through research I have discovered this:
Parallel
2 - 8 ohm speakers = 4 ohms
Series
2 - 4 ohm speakers = 8 ohms
I also realized that I'm going to need a lot more watts, so now I'm looking for a power amp in the 200 watt to 500 watt range. Now the wattage of the amp that I get can either be produced at 4 ohms, 8 ohms, or 16 ohms. So my next question is: Why are parallel woofers bad?
I also found out what a crossover circuit in. All I have to do is put an appropriate capacitor on one side of the tweeter. Should I also make a coil for the woofer? And if so, should each woofer get a separate coil? Sorry that my question has changed but it figure that it is good more readers to know the background info. Thanks for all the help!
Parallel
2 - 8 ohm speakers = 4 ohms
Series
2 - 4 ohm speakers = 8 ohms
I also realized that I'm going to need a lot more watts, so now I'm looking for a power amp in the 200 watt to 500 watt range. Now the wattage of the amp that I get can either be produced at 4 ohms, 8 ohms, or 16 ohms. So my next question is: Why are parallel woofers bad?
I also found out what a crossover circuit in. All I have to do is put an appropriate capacitor on one side of the tweeter. Should I also make a coil for the woofer? And if so, should each woofer get a separate coil? Sorry that my question has changed but it figure that it is good more readers to know the background info. Thanks for all the help!
I've been told by a couple of sound expert type guys that bass guitar needs at least 200 to compete with a drummer. 500 would be crazy, but it would also be awesome lol. A 200ish per channel and 400ish bridged would be a great choice I think. Then I could use 500 watt speakers so that they won't blow, and chose one side of the stereo or go with it all bridged depending on the venue. This makes sense to me. If it doesn't to you guys please tell me!
The stuff I was talking about earlier was information based on this website http://colomar.com/Shavano/2x12wiring.html
This is the circuit I was talking about earlier
I think that if the speaker cab has a large range, it will work well for bass, electric guitar, and vocals(not at the same time.)
The stuff I was talking about earlier was information based on this website http://colomar.com/Shavano/2x12wiring.html
This is the circuit I was talking about earlier
I think that if the speaker cab has a large range, it will work well for bass, electric guitar, and vocals(not at the same time.)
DeadSpeaker said:
What's the venue?
Musical instrument speakers are generally high efficiency, meaning less power for the same spl. For each 3dB increase in efficiency, half the power is needed.
If you bridge a 200 watt per channel amp the resulting power is nearly 4 times that (~800 watts).
REALLY need to know how to do this properly, or kiss your amp goodbye.
Hi,
that post 14 diagram is a cheap way to do an inefficient crossover that started to become popular during the 80s when sensitivity dropped like a stone (from 90db/Wm to 82db/Wm).
The chase has been on (for almost two decades) for raising the sensitivity again and the bass/mid now get a single pole or two pole low pass filter to match the characteristics of the treble driver+high pass filter.
The expensive way to do it, is adopt 3pole filters, but that requires a lot of accuracy in components to productionise any design.
that post 14 diagram is a cheap way to do an inefficient crossover that started to become popular during the 80s when sensitivity dropped like a stone (from 90db/Wm to 82db/Wm).
The chase has been on (for almost two decades) for raising the sensitivity again and the bass/mid now get a single pole or two pole low pass filter to match the characteristics of the treble driver+high pass filter.
The expensive way to do it, is adopt 3pole filters, but that requires a lot of accuracy in components to productionise any design.
If I went with that schematic I would end up with a 4 ohm cab, so I would need to make sure the setting on the amp are always set to 4 ohms. That's not too too big of a deal.
The venue is undetermined. I live around the Richmond VA area where there are a lot of clubs that you can play at. While those gigs are probably a lot harder to get, there are a lot of battle of the bands type things that happen at churches in the area. I wouldn't say I'm in a Christian band or anything, but some of the churches in my area let different bands play at like festival type things to bring attraction to the church.
Andrew, I'm defiantly a visual learner. Do you know of a webpage or of a schematic with an acceptable crossover network?
The venue is undetermined. I live around the Richmond VA area where there are a lot of clubs that you can play at. While those gigs are probably a lot harder to get, there are a lot of battle of the bands type things that happen at churches in the area. I wouldn't say I'm in a Christian band or anything, but some of the churches in my area let different bands play at like festival type things to bring attraction to the church.
Andrew, I'm defiantly a visual learner. Do you know of a webpage or of a schematic with an acceptable crossover network?
If you like pictures with your learnings, you should really like this site by a fellow member.....
http://www.bcae1.com/
It is mostly car audio stuff, but it also explains the basics of amplifiers and speakers as well as other useful things.
http://www.bcae1.com/
It is mostly car audio stuff, but it also explains the basics of amplifiers and speakers as well as other useful things.
Hi,
yes, a crossover has two legs for a two way.
one leg removes the high frequency content and feeds the remainder to the bas/mid.
The other leg removes the mid and lower frequencies and feeds the remainder to the treble driver.
In band each leg presents a very low impedance. The driver sees almost all the signal sent to it.
Out of band the crossover leg presents an ever higher impedance as the frequency moves away from the crossover frequency.
A single inductor in the bass/mid leg and a single capacitor in the treble leg is referred to as a single pole filter. This has an attenuation rate of 6db/octave IF the impedance of the driver stays constant and the efficiency stays constant. BUT the driver is not constant. To get a good result you will need to add other components and even swap some of the components that calculation says are suitable. Two single pole filters will change the phase of the drivers by 45degrees at the crossover frequency.
This creates a small notch in the response due to the 90 degree aggregate error. Again small changes can help reduce this.
Alternatively, go to a two pole filter in each leg. Now you get more attenuation out of band and the speakers are phase shifted by 90degrees at the crossover. Since the drivers are now 180degrees out of phase at crossover frequency, just reverse one of the drivers. This is the route I would recommend,
Your requirements for a guitar amp and guitar speaker are completely different from normal recorded music reproduction.
Your combination must be capable of being "voiced" to suit your music and your style. This is rather specialised. I cannot help with voicing.
yes, a crossover has two legs for a two way.
one leg removes the high frequency content and feeds the remainder to the bas/mid.
The other leg removes the mid and lower frequencies and feeds the remainder to the treble driver.
In band each leg presents a very low impedance. The driver sees almost all the signal sent to it.
Out of band the crossover leg presents an ever higher impedance as the frequency moves away from the crossover frequency.
A single inductor in the bass/mid leg and a single capacitor in the treble leg is referred to as a single pole filter. This has an attenuation rate of 6db/octave IF the impedance of the driver stays constant and the efficiency stays constant. BUT the driver is not constant. To get a good result you will need to add other components and even swap some of the components that calculation says are suitable. Two single pole filters will change the phase of the drivers by 45degrees at the crossover frequency.
This creates a small notch in the response due to the 90 degree aggregate error. Again small changes can help reduce this.
Alternatively, go to a two pole filter in each leg. Now you get more attenuation out of band and the speakers are phase shifted by 90degrees at the crossover. Since the drivers are now 180degrees out of phase at crossover frequency, just reverse one of the drivers. This is the route I would recommend,
Your requirements for a guitar amp and guitar speaker are completely different from normal recorded music reproduction.
Your combination must be capable of being "voiced" to suit your music and your style. This is rather specialised. I cannot help with voicing.
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