100W head, two 2x12 cabinets, four 25W speakers.

[the2x12ammunition]

100W head, two 2x12 cabs, four 25W speakers

I have this dream of buying a 100W Marshall Super Lead, getting two Marshall 1936 cabinets (2x12, RMS 150W), with some 25W greenbacks, two for each cab. Would this be doable in any way without killing the speakers? I know speakers with that wattage would normally be put in a 4x12, but they're kinda huge, plus I really like the look of a stack of 2x12's. Any input is appreciated, and please go easy on me because I don't know that much about amps.

 

[TheKman76]

If the plan is to crank it, you may run into some trouble. A typical 100W Marshall will easily produce a clean RMS 100W. However, when clipped, this can easily exceed the rated power by perhaps 20-30%.

Frankly I don't know where you'd ever get the opportunity to do this outside of an isolated recording space. With even -3dB of attenuation you'll be back inside the limits of the speakers.

Finally, I don't believe the Super Leads ever had a 4 Ohm output, so there will have to be some special wiring involved to make the 2x2x12 cabinet arrangement work.

 

[the2x12ammunition]

But what if I connected the two cabinets to each other somehow? Like connect the amp head with to one cabinet and then connect that first cab to the other one with another speaker cable. Instead of connecting one of the two outs on the back of the Super Lead to each cabinet? Would that effectively make it a 4x12? Is that even possible haha.

If the plan is to crank it, you may run into some trouble. A typical 100W Marshall will easily produce a clean RMS 100W. However, when clipped, this can easily exceed the rated power by perhaps 20-30%.

Frankly I don't know where you'd ever get the opportunity to do this outside of an isolated recording space. With even -3dB of attenuation you'll be back inside the limits of the speakers.

Finally, I don't believe the Super Leads ever had a 4 Ohm output, so there will have to be some special wiring involved to make the 2x2x12 cabinet arrangement work.

 

[fitz]

100W head, two 2x12 cabs, four 25W speakers

I have this dream of buying a 100W Marshall Super Lead, getting two Marshall 1936 cabinets (2x12, RMS 150W), with some 25W greenbacks, two for each cab. Would this be doable in any way without killing the speakers? I know speakers with that wattage would normally be put in a 4x12, but they're kinda huge, plus I really like the look of a stack of 2x12's. Any input is appreciated, and please go easy on me because I don't know that much about amps.

to the forum.
100w Super Lead into a quad of 25w greenbacks has potential for speaker killing, but as @TheKman76 said, where are you planning to crank a 100w?
A 50w 1987 may be a more reasonable amp choice with the same basic tones, and no risk to your speaker choices.

A pair of 1936 cabs (same footprint) is going to be even taller than a 1960 4x12, but easier to move around as separate cabs.
I have a pair of 1922 cabs stacked for my 4210, but they're a bit smaller than the 1936.

Running the 8 ohm cabs through a series box can get you back to a 16 ohm load.
I use a Palmer to do this with my 1922's, even though the amp has a 4 ohm tap.

 

[the2x12ammunition]

Thanks for the warm welcome! So I could pull it off with a series box? And yes I would be planning to crank it (with an attenuator). Also, if that worked with a series box, could I also do the same thing if I had 25 Greenbacks (16 ohms), with some G12-65’s (8 ohms) in the other cab? I know you generally don’t mix different impedances but with a series box, would it be plausible? Or would you essentially need two separate heads at that point, one for each cab?

 

[Kuga]

Once a friend killed a Marshall Vintage speaker (70W) using a Marshall 1936 Vintage (140W) into a TSL100. I saw It in live time. A tech replaced a speaker coil. He still use his TSL into a 1936 Vintage cabinet. Maybe someday kill the other speaker. Who knows.

You can find 1936 cabs with 25W greenbacks. I have two of them. Actually I have installed G12H30 on them. Here two Marshall 1936G/GS.

 

[the2x12ammunition]

How do you hook this up? Do you use one of the speaker outs on the head for each cabinet or do you plug them into a series box or something like that? And how loud are you running it usually?

Once a friend killed a Marshall Vintage speaker (70W) using a Marshall 1936 Vintage (140W) into a TSL100. I saw It in live time. A tech replaced a speaker coil. He still use his TSL into a 1936 Vintage cabinet. Maybe someday kill the other speaker. Who knows.

You can find 1936 cabs with 25W greenbacks. I have two of them. Actually I have installed G12H30 on them. Here two Marshall 1936G/GS.

View attachment 154860

 

[Purgasound]

Superleads absolutely have 4 ohm taps. The claim that they do not is demonstrably false.

I run a Superlead through a single 4x12 with Greenbacks reissues a few times a week. It's not a problem. Celestion themselves will say there's not an issue here. A couple records back we used a Greenback cab for quite a few songs. A 100W Marshall was cranked and ran through it for an extended period of time and it still works fine.

When it comes to speaker wattage rating most manufacturers will rate them with peak and RMS voltage. A guitar amplifier will never put out anything RMS since amplified guitar waveforms have tons of peaks and dips. I don't know to what method they choose their rating but it is considered a safe average. The voice coil relies on those pauses, and dips to stay cool. This is why speaker break in methods using a sine wave are never a good idea. The voice coil never has a chance to cool even at lower volumes. There's a great interview with one of the designers at Jensen where they go into detail about this.

Cheers

 

[Kuga]

How do you hook this up? Do you use one of the speaker outs on the head for each cabinet or do you plug them into a series box or something like that? And how loud are you running it usually?

I use speakers outs on the head. The 1936 cabs are 8ohm each one. Speaker outputs set at 4ohms on the amp. Also I have a serial connection cable ( made It myself)to get a 16ohms load to use them on a LM6100 or JCM900s because this heads don't have 4ohms speaker outs. On the picture you can see an Astoria Custom. It's a 30W amp. I can play at full volume with this amp. When I want play really loud with a 100W amp I use more speakers. This two 1936 with a serial cable (16ohms) and then a 4X12(16ohms) into 8 ohms speaker outputs on the 100W amp.

EDIT: When I bought brand new my '98 TSL100 It used two 1936 JCM900 Lead cabs (150W each one). Two 1936 stack looks great and sounds fine but a 1960 cab sounds deepest.

 

[Georgiatec]

100W head, two 2x12 cabs, four 25W speakers

I have this dream of buying a 100W Marshall Super Lead, getting two Marshall 1936 cabinets (2x12, RMS 150W), with some 25W greenbacks, two for each cab. Would this be doable in any way without killing the speakers? I know speakers with that wattage would normally be put in a 4x12, but they're kinda huge, plus I really like the look of a stack of 2x12's. Any input is appreciated, and please go easy on me because I don't know that much about amps.

If you're going to put your own speakers in the cabs, just get 8 ohm versions of the Greenbacks and wire them in series for 16 ohm loads. 16 ohm cabs are way more versatile than 8 ohm. You may want to use one in the future with an amp that only has a 16 ohm tap.
It's unlikely you'll blow the speakers as folks just don't play 100w amps at full chat without attenuation these days. Back in the day, it would need continued use over some time with the amp cranked to blow them. However it did happen. The 25w speakers were used when two 4 x 12's were the way to go (Full Stack). Later in the '70's the trend for only using an "A" cab led to speakers blowing. Marshall then started to fit the newly available G12-65 into their cabs.