2x12 cabinet 8 ohm or 4 / sound difference

[sashjo]

hi all

can anyone tell me if there is a difference in sound if i wire 2x12" speakers
8 or 4 ohm? the amp puts out 45 watts. both speakers would be rated at 50 watts.

thanks

jc

[Plague Dog]

two 8 ohm speakers are either going to be 16 ohms in series or 4 ohms in parallel. There is no wiring configuration I know of that will net either 4 or 8 ohms with two eight ohm speakers.

[Plague Dog]

Two speakers wired in parallel will double the power, 2 x 50 watt speakers = 100 watts
In series each speaker will carry half the load 2 x 50/2 = 50 watts.

with parallel wiring the amp will see twice the load and run slightly hotter. If your output transformer is capable of carrying the extra heat generated than you will have no problem.

[sashjo]

thanks for the help.

that answers my question. not sure if the transformer has enough muscle for the 100 watt setup.
i have to check with the amp builder.

thanks again

jc

[scottl]

Speaker power handling has no effect on that you said. It is just how much power the speakers can take. All things being equal, the 8 ohm speaker tap will be running more tranny winding and may have better bass handling ability. Some, like Steve Kimock, have expounded on always using the highest ohm tap for this very reason.

Do you have a selector switch or seperate speaker jacks? Try and keep the ohms matched.

Originally Posted by sashjo

thanks for the help.

that answers my question. not sure if the transformer has enough muscle for the 100 watt setup.
i have to check with the amp builder.

thanks again

jc

[pgissi]

Using medium to high gain OD as a reference

Series wiring- mid/upper mid and high end emphasis generally, smoother high freqs generally due to damped top end highs in the 5 to 6k range, less fizz. Additional tonal changes are slightly spongier attack and altered OD character, more complex and timbrally rich with more overtones ala the mid and top end emphasis.

Parallel wiring- low end and lower mid emphasis with more top end high sparkle or fizz, depending on the speaker and rig that can make the high end raspy or harsh to some. Low end is emphasized due to increased damping between 2 12" speakers in parallel, generallly tighter and more thump.

Think about how low end and sub cabs for Pro Sound Sys are parallel for better bottom due to coupling or dampening if in the same cab, it applies universally

Its impossible to predict how your rig will sound to your liking with either, try them both.

I had the fizz in my amp and wanted a smoother top using the same speaker. The Fizz can be that busy bee hive above your sound that robs your tone of clarity with medium or high gain tones and fast playing on the high strings. Clean or low gain OD tones are a different story and IMO parallel is better but since I mostly play with medium to heavy OD, and OD has the most potential to be painful if not as pleasing as it could be, I go for harder but smoother OD, more old school if you will.

I now use 2, 8ohm Series wired 12" speakers to get a more present upper mid and smoother top end OD with less harshness after trying 2 16ohm in parallel for 8 and 2 8ohm in parallel for 4ohms. When you think of speaker power handling just be concerned that your speakers can handle your ampos output in total but dont be afraid to reduce headroom if you want earlier onset of OD ala Speaker Breakup for a lower volume OD

You can generalize that more powerful speakers have later onset of breakup and vice versa which means you may need to be louder to get to X amount of OD, ignoring the tonal differences for the moment.

Just another aspect in addition to Series versus Parallel wiring.

Another observation and its my opinion but my ears tell me-

Parallel- for heavier OD tones, more modern tone as in todays tuned down uber bottom tones with raspy highs, tighter thump think Tool etc

for cleans, more headroom and usable travel on the guitar pot, more high end sparkle in the 5 to 6k range since the parallel spkr coil config means the extreme high end is not attenuated through each coil in series

more hifi sounding in general with bottom and very top end emphasis

Series- more vintage flavored with less bottom more mids and top end but not as extended into the Presence range of 5 to 6k more suitable for shred where you spend much time on strings 1, 2 and 3 etc. speed picking etc. Too much presence and its Razer Blades to the ears

Less headroom overall meaning less clean and its dependent on the rig of course


P.S. When it comes to clean or light OD to some medium tones, the results may not play out as I have described since the speakers are probably not in breakup.

My observations on Series and Parallel differences were made using medium to high OD tones and then a clean tone test simply by bypassing any OD pedals, backing down guitar pot. The same 2 tests were done with and without pedals for comparison and to eliminate any pedal coloration.

Parallel was 1st- OD was ok and clean was very nice for being able to get to scream with just a turn of the guitar pot, not channel switching

Series- OD improved dramatically for harder styles and tones but clean suffered, oh well


Try all and nay config in every which way to find the best for your rig and tastes

[sashjo]

i do have an ohm choice.

4, 8, 16 ohm on the amp head.

[Plague Dog]

Think about a 4x12 cabinet. Usually they are wired with 4-16 ohm speakers, two pairs, each series wired and than put into parallel

series 16 x 2 = 32, pairs wired parallel /2 = 16 ohms

so you could consider the vintage marshall tone to be a series tone, the signal path goes through two complete voice coil windings.



I think most people prefer the series wired smoothness because that is much more forgiving.

[sashjo]

i'm definitely not a fast pickin' rock shredder. most of the time i like mild overdrive or the sort of clean with fur around the edges.
i love the feel and depth of a cabinet with big low end. i'm into beefy big chords but not power chords. like fat old school soul rhythm.

but.....i definitely need the sparkle.
blues, alt country rock. think buddy miller, albert collins, freddie king, .......sonically that is.

hate to use other players names but just as references.

still..i get it that it's all so subjective the only thing i can do is use my ears.
i've got a Bob Burt V 2x12 coming soon and was just looking for a place to start.
.....like a general rule.
thanks so much for all your input. it helps.

Originally Posted by Plague Dog

Two speakers wired in parallel will double the power, 2 x 50 watt speakers = 100 watts
In series each speaker will carry half the load 2 x 50/2 = 50 watts.

Is this information correct? With either series or parallel wiring, the cabinet wattage capacity is the sum of the lowest speaker wattage. i.e. Regardless of wiring, the 2 - 50 watt speakers would make a 100 watt capacity cabinet. When using mixed wattage rated speakers, the lowest speaker is doubled. i.e. a 30 watt speaker plus a 50 watt speaker does not make an 80 watt cab. It would make a 60 watt cab.

[pgissi]

Think about a 4x12 cabinet. Usually they are wired with 4-16 ohm speakers, two pairs, each series wired and than put into parallel

series 16 x 2 = 32, pairs wired parallel /2 = 16 ohms

so you could consider the vintage marshall tone to be a series tone, the signal path goes through two complete voice coil windings.

I think most people prefer the series wired smoothness because that is much more forgiving.

Some cabs like the marshall 1960 series with the stereo split switching are 2 pairs parallel wired then in series for the mono setting @16ohms since when doing the split, using 2 16ohm spkrs in series in stereo mode is too high of an impedance for any amp. Best thing is not to assume about a cab, open it up and check it. I have a 1960a and found the pcb and switch can accomodate series-parallel wiring but it eliminates the stereo option and disables 1 jack, makes the cab mono only, I am not missing stereo

A poster in another thread mentioned that he hears people say the older cabs sound better but are not aware of the change in wiring from the original series-parallel to the parallel-series with the intro of the stereo option, its a different tone.

Of course not all cabs but its not something mentioned in the spec and is least considered in the tone quest.

i'm definitely not a fast pickin' rock shredder. most of the time i like mild overdrive or the sort of clean with fur around the edges.
i love the feel and depth of a cabinet with big low end. i'm into beefy big chords but not power chords. like fat old school soul rhythm.

but.....i definitely need the sparkle.
blues, alt country rock. think buddy miller, albert collins, freddie king, .......sonically that is.

hate to use other players names but just as references.

still..i get it that it's all so subjective the only thing i can do is use my ears.
i've got a Bob Burt V 2x12 coming soon and was just looking for a place to start.
.....like a general rule.
thanks so much for all your input. it helps.

I would think you would prefer parallel-series, you'll like the low end and have less breakup in the mids and highs generally, will also have more usable travel on your guitar pot for easy cleanup for alt country rock, the cleans will be fat and full or thin and clear depending on guitar etc.

Its generally a better clean tone versus series-para, I noticed this with my slx which is a high gain amp, it cleaned up better and easier, did not have to find that sweet spot, it seemed to be wider on the pot and had more low end with para-ser but has a more happening OD with ser-para and since thats what it needed most.

But try both so you'll know with your gear which is best

There is a good tone generalization to use as a reference, fender amps with the lower impedance spkrs in parallel for combos and in contrast marshall series-para wired cabs to complement that tone.

One is naturally cleaner and the other dirtier.

Is this information correct? With either series or parallel wiring, the cabinet wattage capacity is the sum of the lowest speaker wattage. i.e. Regardless of wiring, the 2 - 50 watt speakers would make a 100 watt capacity cabinet. When using mixed wattage rated speakers, the lowest speaker is doubled. i.e. a 30 watt speaker plus a 50 watt speaker does not make an 80 watt cab. It would make a 60 watt cab.

Sounds about right or is a good conservatve assumption, the 30 watt speaker is the weakest link

[sashjo]

I think parallel-series is the wiring configuration I'll go with.
Lord knows it's not that difficult to experiment.
Thanks again for all the advice and knowledge.

JC