Guitar speaker installation

With both parallel and series wiring of multiple speakers, the total impedance load changes compared to running a single speaker. Let's take a look at each method, along with what happens in terms of the total load and power handling capability with each guitar cabinet wiring approach.

Parallel wiring connects each of the speakers directly to the amplifier's output, with wires from the positive terminal of the amp's output routed to the positive terminal of each speaker, and wires from the negative terminal going to the negative terminal on each speaker.

The other option is series wiring. For series wiring, the positive output terminal of the guitar amplifier is connected to the positive terminal on only one of the speakers. The negative terminal of that speaker is then connected to the positive terminal of the second speaker, and the second speaker's negative terminal is connected to the negative terminal on the amplifier.

Series wiring has the opposite effect on total load impedance as parallel wiring does. When guitar speaker cabinets are wired together in this way, you add the impedance of all the speakers together to arrive at the total load value, so those same two 8 ohm speakers present a 16 ohm load to the amplifier when they are wired in series. As with parallel wiring, two 50W speakers wired in series can handle up to W.

When we move on to even larger guitar speaker cabinets with more drivers, such as the classic 4x10 and 4x12 speaker enclosures, series and parallel wiring configurations are still possible, but a third option also opens up. This is a combination of the two previous guitar speaker cabinet wiring methods, and is called series-parallel wiring. First, here's a couple of illustrations to show parallel and series wiring with four speakers.

Both of these wiring configurations are sometimes used, but many cabinets with four speakers use series-parallel wiring instead. To connect the speakers in a 4x12 cabinet with series-parallel wiring, the four speakers are wired together using a combination of the series and parallel wiring techniques.

The advantage here is that the total load for the cabinet remains the same as the value for a single speaker. If you wire four 16 ohm speakers together with series-parallel wiring, the nominal speaker load for the cabinet will remain 16 ohms. Four 8 ohm guitar speakers in a series-parallel configuration will give you an 8 ohm cabinet. Multiple guitar speaker cabinets can be connected to a single amplifier, just as long as you match impedances and don't go below the amplifier's minimum load.

If an amp can run at 8 ohms, connecting two 16 ohm cabinets to it with parallel wiring will result in a safe, 8 ohm nominal load, while connecting two 8 ohm cabinets with parallel wiring will give you an unsafe 4 ohm load. It's much less common, but if special cables are used and the guitar speaker cabinets are wired to each other and to the amp with series wiring, two 16 ohm cabinets will give you a 32 ohm load, while two 8 ohm cabinets will yield a 16 ohm load. Well, there you have it - the basics on how to wire guitar speaker cabinets.

Of course, this isn't all there is on the subject. It is possible to use speakers with different power handling capacities and even different impedances in the same cabinet, but this requires more math and much more careful consideration, and all of that is a subject for another day, another article….

He is a former featured monthly columnist for EQ magazine, and his articles and product reviews have also appeared in Keyboard, Electronic Musician and Guitar Player magazines.

Posted August 20, I have a lot to learn about this wiring stuff. All in due time though. You got to start somewhere though right? I have been taught that speakers in series have phase cancellation and loose some of the low end. I remember the first time I re-wired one of these monsters - my eyes nearly popped out on comedy springs: there were wires literally everywhere! However, I persevered and worked out exactly what was going on. From that point on nothing was as tricky as it once seemed.

If you decide to try to fit a used or vintage speaker in your amplifier, then there are a few things you should do to confirm its functionality beforehand. Firstly, examine the speaker for any tears or holes. There should be none. If there are any, these will cause the speaker to sound bad and possibly tear more and then fail altogether. The next thing to look for are the small linking wires from the tags to the speaker cone. These should be perfect and not broken or damaged.

Lastly, lie the speaker on its magnet and very carefully place your hands on the cone itself. Try gently moving the cone in and out, carefully feeling for any scraping or resistance between the voice coil and magnet as you do so.

If it moves smoothly and freely, hopefully you should have a good speaker. For replacing the speaker itself, you will need a good soldering iron or solder station, between 25 and 40 watts will be perfect.

You will need some solder; lead-free is the norm these days, but I do still like the oldschool lead solder. Now, lie your amplifier or cabinet on its face and remove any back panels and so on that may be in the way. On my own amplifier, I found it much easier to also remove the reverb tray from the bottom part of the amplifier. This made for much easier access to the lower speaker nuts. My amplifier has a separate plugged-in speaker cable, so it was a simple unplug job. With a hard-wired speaker output that some amps have, we would have to unsolder the two wires from the speaker - taking notice of which is positive and negative.

Next, unscrew the four or eight screws, nuts or bolts holding the speaker in, being careful not to drop these into the speaker or, worse, into the amp itself , never to be seen again! You should then be able to lift the speaker out of the amp. If your speaker cable was a plug-in job then now is the best time to re-solder it onto the new speaker.

Fit the speaker back into the cabinet and start to screw or bolt it back down. At this point I must stress, as I have done before, please do not over-tighten the speaker bolts. On a pressed-chassis speaker it can be very easy to bend it out of true, and this can cause speaker distortion and odd overtones.

A simple rule is get it finger-tight and then go a quarter-turn more. Then you can get cranked and listen to your new baby sing. Every new speaker will have a break-in period, so give it time to soften up and it will get better every time you play. At this point you should be pretty happy with yourself, as I was after my first rewire of the big old monster Marshall.

Read on to see how our group of inch speakers, all built to different power ratings with different musical applications in mind, changed the sound and feel of our test amp when we fitted them, one after the other, into the same Deluxe Reverb…. During the making of this feature, I was able to fit and compare six different types of inch Celestion speaker in my old Deluxe Reverb, including original vintage models, writes Simon Law. After putting each speaker through its paces with clean tones first, a Maxon SD9 Sonic Distortion was used for overdrive.

Here are the results The first speaker on the test bench was the Celestion Alnico Gold. The rating of this speaker is 50 watts as opposed to the watt rating of the original Blue variety.

It features an Alnico magnet and a small voice coil, and all of this adds up to a very vintage and sweet-sounding speaker. According to Celestion, these speakers are modelled on a nicely worn-in original, and I can hear this during our test.

The treble response is chimey with a hint of natural compression. I would rate this speaker highly for early blues and rock tones - but even for country playing, where the compression helps a clean note sing. Next up was an old favourite of many players, the Classic Lead This speaker is rated at 80 watts. It came onto the scene in the late s when guitarists needed a bigger, bolder speaker for lead playing. I found this speaker sounded best when used with the amp cranked up loud and not so much when used with an overdrive pedal.

I would rate this speaker for big, powerchord playing and old-school hair metal where you need to move air without making ears bleed! And it gets a big thumbs up for those Spandex and hairspray moments…. The top end was smooth with no harshness at all. This speaker sounded great when pushed hard and when used with an overdrive pedal. Again, maybe not the best match to this particular amplifier. For me, this helped the chimey sound of my amp really shine through without being muddied by excess midrange.

When pushed hard, there was a lovely amount of overdrive that was consistent right through the spectrum. This is a very good speaker. It had such a three dimensional tone, you almost imagine you were playing in stereo! The last two speakers on the bench were a couple of original vintage drivers, both well-loved types harking back to the s.