Speaker advice for 1960bx - replacing G12M 20 watt

pdxfairview

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Longtime Fender guy here new to the Marshall world. After much research I purchased a 1979 JMP 2004 and a new-ish 1960bx. The previous owner of the 1960bx replaced the stock speakers with G12Ms, specifically the 20 watt / 15 ohm version.

And...I think it's not for me. The speakers specifically. They sound thin and "paper-y" to my ears. While at the repair shop, I had the chance to hear the head through a different cab (homemade, mix of speakers) and it sounded waaaay different - ie, better. Which just confirmed to me how much of a difference speakers make.

The cabinet itself is immaculate, and it's got the checkerboard grill cloth I like, so I'm thinking I'll swap out the speakers. Leaning toward the G12T-75. Is this nuts? I know most people go the other direction...swapping their G12T-75s for greenbacks.

One thought was to start with two...swapping the top two just as a first step. But the existing G12Ms are 15 ohm rather than 16. So I'd have two 16 ohm speakers in the top row and two 15 ohm speakers in the bottom row. I assume this wouldn't be an issue for the amp, but would the G12Ms be louder (b/c less resistance)?

Thanks!

1 (5).png 1 (4).png
 

fitz288

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:welcome:
The 15/16 ohm thing is no big deal.
Loudness is more in the sensitivity.
The G12T-75's will be a little louder, so put them on the bottom.
Keep in mind your total cab wattage will still be limited by the two remaining 20w G12M's
And send me those greenbacks, I'll pay the shipping and give you some brand new Seventy-80's. :D

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pedecamp

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Longtime Fender guy here new to the Marshall world. After much research I purchased a 1979 JMP 2004 and a new-ish 1960bx. The previous owner of the 1960bx replaced the stock speakers with G12Ms, specifically the 20 watt / 15 ohm version.

And...I think it's not for me. The speakers specifically. They sound thin and "paper-y" to my ears. While at the repair shop, I had the chance to hear the head through a different cab (homemade, mix of speakers) and it sounded waaaay different - ie, better. Which just confirmed to me how much of a difference speakers make.

The cabinet itself is immaculate, and it's got the checkerboard grill cloth I like, so I'm thinking I'll swap out the speakers. Leaning toward the G12T-75. Is this nuts? I know most people go the other direction...swapping their G12T-75s for greenbacks.

One thought was to start with two...swapping the top two just as a first step. But the existing G12Ms are 15 ohm rather than 16. So I'd have two 16 ohm speakers in the top row and two 15 ohm speakers in the bottom row. I assume this wouldn't be an issue for the amp, but would the G12Ms be louder (b/c less resistance)?

Thanks!

View attachment 96274 View attachment 96275
First off brother man welcome to the forum and what a beautiful rig you've got! Youre not nuts, I love greenbacks but not with a 2204, I have a 2x12 with 75's and love it! I have a pair of creambacks on the way for my 1959 and I'll try them with the 2204 too since I use the same cab for both amps. Take your amp to any music store that carries Marshall and plug it into a 1960 cab to see how you like 75's. 15-16 ohm is the same thing so dont worry about it.

Something else you want to check with your cab is make sure its wired right and not out of phase or speakers blown. The greenbacks shouldnt sound thin and paper-y, I have a greenback 2x12 for my SV20H and it doesnt sound anything like that.
 
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Gene Ballzz

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@pdxfairview
AGAIN> :welcome: to the forum!

AND NEXT> I strongly second the suggestion to check the speaker wiring to confirm proper phasing/polarity. Even one speaker out of phase with the others will absolutely ruin the sound of the whole cabinet! An easy way to check is with a 9-volt battery and a speaker cable. With the cabinet back removed, plug the cable into the cabinet and touch the terminals of the battery onto the two terminals (tip and sleeve) of the cable, and determine that when the speakers pop/move, they all move the same direction with the +positive and -negative of the battery always oriented the same way. With the kind of wire shown in your pic, it is not difficult to get +positive & -negative mixed up. A pic of what kind of jack/jack plate you have might also help?

Great looking rig!

Let Us Know?
Gene
 

clutch71

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@pdxfairview
AGAIN> :welcome: to the forum!

AND NEXT> I strongly second the suggestion to check the speaker wiring to confirm proper phasing/polarity. Even one speaker out of phase with the others will absolutely ruin the sound of the whole cabinet! An easy way to check is with a 9-volt battery and a speaker cable. With the cabinet back removed, plug the cable into the cabinet and touch the terminals of the battery onto the two terminals (tip and sleeve) of the cable, and determine that when the speakers pop/move, they all move the same direction with the +positive and -negative of the battery always oriented the same way. With the kind of wire shown in your pic, it is not difficult to get +positive & -negative mixed up. A pic of what kind of jack/jack plate you have might also help?

Great looking rig!

Let Us Know?
Gene
My thoughts exactly. Thin and "papery" are def not how I would describe these speakers. SHould be some resources on this forum.
 

jeffb

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I liked the GB reissues better than the Heritage Reissue GBs, M2C.

I have struggled with this over the years.. the 25 RI vs 20 (heritage/EVH) new production...some days I prefer the 20s, some days the 25s. If they could get the thicker mids of the 20s and keep the crunch, lows and top end sizzle of the RI 25, it would be perfect. But they just can't seem to get there. Maybe they are not trying, IDK.

Running a mix is the best solution I have found. But I think if I HAD to choose, I'm with you- a good set of the 25 RIs
 

Biff Maloy

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The performance description of the cab doesn't sound right. Definetly check the wiring and confirm they are all in phase and the ohms are correct. I also wonder if those 20s are broke in good.

I haven't done a 4x12 of Heritage 20s but they are one of my favorites. I've had a pair of Celestion EVH 20's in my 2061CX for a while now that I use with my SV20H. I like them. The best combination in that cab to me is a Heritage G12M20 and Heritage G12H 55hz. The 55hz is louder but they sound good together.

If you do end up changing them I'd recommend some Heritage 75hz mixed with the 55hz.
 

Matthews Guitars

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20 watters should sound magical. Like this.




But then again, these are originals Johan is playing. Not sure how well reissues would compare.

But, based on my experience with G12M25 originals vs. reissues, I'd have to expect them to be reasonably close.
 

jeffb

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The best combination in that cab to me is a Heritage G12M20 and Heritage G12H 55hz. The 55hz is louder but they sound good together.

If you do end up changing them I'd recommend some Heritage 75hz mixed with the 55hz.
Excellent combo- I concur. The 12M20 smooths out the extended highs and hard bass of the heritage 55hz. It sounds more like (but not exactly like) an older Pulsonic 55hz.
 

Dogs of Doom

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depending on what it is you're doing in your musical life, you might want to do some testing in practical use.

I had a cab, that was loaded w/ GB25's. (the Chinese ones) I didn't like the sound of them. I tried them in every cab I have & just did not like the sound in the room.

I did do a lot of testing, recording them & funny thing is, that the recordings sound great, while the room sound was uninspiring. Even so much so, that, I have speakers that are much more inspiring, in the room, but, I don't get as good of recordings, as easily.

So, if recording is your goal, try out some recording, you might end up liking them more than you think.

In my case, I sold my GB25s off, because I didn't like the room tones. Listening back, I wish I still had them.

Good thing I can get them pretty much any time, but, I should have just kept them...
 

jeffb

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depending on what it is you're doing in your musical life, you might want to do some testing in practical use.

I had a cab, that was loaded w/ GB25's. (the Chinese ones) I didn't like the sound of them. I tried them in every cab I have & just did not like the sound in the room.

I did do a lot of testing, recording them & funny thing is, that the recordings sound great, while the room sound was uninspiring. Even so much so, that, I have speakers that are much more inspiring, in the room, but, I don't get as good of recordings, as easily.

So, if recording is your goal, try out some recording, you might end up liking them more than you think.

In my case, I sold my GB25s off, because I didn't like the room tones. Listening back, I wish I still had them.

Good thing I can get them pretty much any time, but, I should have just kept them...

They vary so much from speaker to speaker, too. I've had several of more recent made in UKs, as well as MIC GB25s and 70th Annies- some just don't sound that good. In the past IDK, 8 or 10 years I've had 2 of each of the GB RI and one MIC was great, and one was absolutely awful. Unfortunately I accidentally ripped the cone of the good one. I have one UK that was just OK, and one that is absolutely fantastic. 4 speakers-same exact model. For my EVH, I have one really great one, and one that sounds pretty good, but doesn't sound nearly as good.

It's like guitars. Play 6 Les Pauls- they will all sound different.

And yes- room sounds and recordings are two entirely different things.
 

tonefinder

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You already tried the amp through a different cab at (presumably) the same volume, so there's your null test and yes, the problem could be the speakers, as you say.

BUT- have you played your rig really, really loud? Because once the master volume reaches a a certain point, that 2204 becomes a fire breathing dragon. Before that point, it can have the weak characteristics you described.

Here's my 2204 plugged straight in, with a mx of vintage speakers. (One of them is a 25w Creamback, similar to yours):

https://drive.google.com/file/d/1RNvWAhePhK1xIBF3ZJo1_JFIsQkcitv6/view?usp=sharing
 

NoelH

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OK, so Mr. PDX, great question, but like many things in the world of guitar, you will have to decide what floats your boat.
I will assume 'papery' means that 'wooden' character many like about early green or blackbacks. In part it's due to the voice coil former material (in your case, paper) and magnet weight. Those speakers also tend to not handle bass frequencies well.
FYI, G12-75's are about the most hated Celestions. I personally cannot stand them. To my ears, they're sterile and harsh, and have a narrow, unattractive midrange. YMMV. But with a 2204, I'm betting they'll grate on you in the long run.

So here's my favorite 4x12 speaker mix goes like this (X-pattern):

2x Weber Blue Bell 100's with Hemp cones.
2x Celestion Vintage 30's.

I used to dislike V30's but found if you mix them with a mellower speaker (like the Hemp Blue Bells), they sound phenomenal. These two in combination will give you sweetness, and the ability to cut through a band mix.
I run two different amps through these: a 50 Watt boutique build that has similarities with the Jubilee, and a DSL 50.

Remember, if you three guitarists, you'll get four or five answers, so this is my answer! Happy experimenting! :cheers:
 

Marshall50w

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Tonight I hooked up my JTM45 to the pair of G12M 20 watter’s in my Marshall 1973X Combo. These are ‘aged’ speakers apparently. Sounded great, exactly what I want to hear from a Marshall. They certainly don’t sound papery/thin !
 

Scumback Speakers

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20 watters should sound magical. Like this. But then again, these are originals Johan is playing.
I have to say, I just don't believe how Johan Segeborn flip flops on recording. He does speaker demos with three mics on the speaker...one near the grill cloth, one 4-5 feet away, and then a room mic placed somewhere near the back of the room 20 feet to who knows how far back. Then he mixes them, does them individually (he says), and blends them.

But here, the cab is close mic'd only for these vintage 20w speakers. His inconsistent recording techniques speak volumes of his experience with recording...or understanding of it. So I'm just pointing out that he's no speaker recording expert, and his opinions/reviews need to be taken with a huge grain of salt...or the entire bag.

To the OP/pdxfairview: You need to double check your wiring to make sure you have that cab wired correctly, in series/parallel, or parallel/series. Your Heritage G12M's might be ok, but if even one wire is off, they're going to sound thin, lack bass, and without fullness.

Speaker wiring diagrams for 4x12's here:
http://www.scumbackspeakers.com/wire.html
 

Biff Maloy

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Testing a cab is the first thing i do before i ever plug an amp into it. New or used but especially if it has been modified like this one.
 

Kinkless Tetrode

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If you liked the G12T75s, then you should consider the G12-65 as well. The G12T75 was developed from the G12-65. Both feature a large dust cap, which is a different from most other Celestions, particularly Greenbacks.

The G12T75, particular the most modern examples, is known to have a scooped sound.

The G12-65 was the speaker of the later model JMPs and early JCM800s.
 

neikeel

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First off brother man welcome to the forum and what a beautiful rig you've got! Youre not nuts, I love greenbacks but not with a 2204, I have a 2x12 with 75's and love it! I have a pair of creambacks on the way for my 1959 and I'll try them with the 2204 too since I use the same cab for both amps. Take your amp to any music store that carries Marshall and plug it into a 1960 cab to see how you like 75's. 15-16 ohm is the same thing so dont worry about it.

Something else you want to check with your cab is make sure its wired right and not out of phase or speakers blown. The greenbacks shouldnt sound thin and paper-y, I have a greenback 2x12 for my SV20H and it doesnt sound anything like that.

the incorrectly wired thing sounds like the issue to me.
My favourite with an MV is 65s but there is something wrong with the set up as is.
 
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