Two basically identical Marshall 1960A cabs->different sound

[Setneck]

Hi!

Imagine two 1960A cabs from the same year (1996), so same speakers, same internal cables, same wood, aprox. same playing time, everything is totally the same. But both sound totally different.

One is very bright and in-front sounding, and the other is dark and dull, very muffled and muddy. The tone is like there's a blanket on the cab. I changed two upper speakers in that second cab for known good 75's - no change for better. The amp is Splawn Quickrod but similar impression was while using Bogner XTC.

What's wrong? Any solution for that second cab? Note that I want to keep the 75's there as their tone suits to what we play.

Thanks in advance, Andy

 

[hunter]

-Are they surely wired the same? There can be a noticeably difference between Series/Parallel or Parallel/Series, even if they're electrically the same
-Center Pole makes good connection to the back panel on both?
-Could the Screws of speakers or back panel be tighter on the bright cab?
-Do the cabs sound very different when you knock on them to test resonance?

My tip would be to get rid of the bad sounding one and buy a good sounding one instead.

 

[PeteLaramee]

--Could the Screws of speakers or back panel be tighter on the bright cab?

This was my first thought. I bought an old Marshall cab a few years ago and I had to tighten all the screws on the front and back of the cab. Once I did it sounded much better.

 

[Setneck]

-Are they surely wired the same? There can be a noticeably difference between Series/Parallel or Parallel/Series, even if they're electrically the same

I'll be able to check that not before tomorrow unfortunately. but You are third guy telling about checking the wiring. I could think that same cabs have same wiring but who knows .

-Center Pole makes good connection to the back panel on both?
-Could the Screws of speakers or back panel be tighter on the bright cab?

That was the first thing I did to mine cab - tighten the screws. No difference after doing this.

Do the cabs sound very different when you knock on them to test resonance?

What do You mean by that? How can I do such test? Just knocking disconected cabs by hand?

My tip would be to get rid of the bad sounding one and buy a good sounding one instead.

Well, that can be done in every moment. But maybe it wouldn't be neccesary, as in Poland where I come from it's quite easy to buy a gear but no so easy to sell it .

Thanks for the tips anyway.

Regards, Andy

 

[rcm78]

Also, make sure all four speakers are in phase... You can do this with a 9volt battery. Touch the battery to the speaker terminals and observe the cone, It will move in or out. Do the same to the other three and make sure they all move in the same direction. If one or more speakers are out of phase reverse the wiring to those speakers.

It's important to make sure you touch + to + and - to - with the battery on all four speakers for a uniform test.

 

[BeZo]

I would re-wire them both anyways. Every Marshall cab I've ever had my head inside had shit for wiring. Plus, I would never trust those switches they put on the jack plate. They arch and blow stuff up. Bad scene.

Get some fatty speaker wire and re-do both cabs. Then try it out.

 

[rcm78]

Just realize that rewiring the cab wont fix the problem if the speakers are out of phase...

 

[Setneck]

I checked almost everything in both cabs and it seems that I have found the reason. Which is WOOD .

Yesterday I opened both cabs and checked the wiring and speakers. They were totally the same. The speakers have had even quite close serial numbers. After that , followed by the tip given by the other forum's user, I knocked a few times both cab's sides with the fist. And while one cab's box was responsing brightly the other's response was dull and muffled.

The difference in wood response is equal to the difference in overall sound. So the speakers and everything else is working fine. So now either I have to find other box or buy complete cab. Fortunately I have a good sounding specimen to compare with .

Thanks for everyone for help and tips

Regards, Andy

 

[blackba]

Interesting that it turned out to be the wood. Unfortunately that is not really something you can address other than just selling the cab and even then someone else gets a dead cab.

 

[Gainfreak]

I checked almost everything in both cabs and it seems that I have found the reason. Which is WOOD .

Yesterday I opened both cabs and checked the wiring and speakers. They were totally the same. The speakers have had even quite close serial numbers. After that , followed by the tip given by the other forum's user, I knocked a few times both cab's sides with the fist. And while one cab's box was responsing brightly the other's response was dull and muffled.

The difference in wood response is equal to the difference in overall sound. So the speakers and everything else is working fine. So now either I have to find other box or buy complete cab. Fortunately I have a good sounding specimen to compare with .

Thanks for everyone for help and tips

Regards, Andy

I can tell you with 100% certainty that the wood will make a HUGE difference. I have 2 Marshall cabs from the 80's and one sounds good and the other sounds like complete crap. Ive tried everything with this cab including speaker swaps, screw tightening, different wiring and nothing worked. I figured that it was the wood and just to be 100% certain that it was the wood, withought unsoldering anything, I took out the speakers from my other Marshall cab and put them directly into the crap sounding cab and it had the same result. Sometimes you just get a dead sounding cab and there is NOTHING that you can do about it. The real trick is to make sure that you have tried the little things first like everything that was mentioned in this thread before you conclude that it's the wood but more often then not, aa shit sounding cab remains a shit sounding cab. This is the main reason why these days I will not buy a cab without trying it first
Carl Roa will also tell you how bad my Marshall cab sounds because he heard it

 

[hunter]

Not sure if it's the material or the construction. One would assume that on laminated birch, differences between the different layers equalise themselves out, so that on average one laminate board sounds like the other. So I thought it has more to do with how snug they are cut, dovetails are done right whatever...

But it's a fact that two boxes made of the same ingredients can sound very different.

 

[rcm78]

Check the speakers individually. I've seen speakers wired incorrectly...meaning the positive tab was actually negative, etc.

YES!!! Check the speakers!!!

 

[Anonymous]

Also, make sure all four speakers are in phase... You can do this with a 9volt battery. Touch the battery to the speaker terminals and observe the cone, It will move in or out. Do the same to the other three and make sure they all move in the same direction. If one or more speakers are out of phase reverse the wiring to those speakers.

It's important to make sure you touch + to + and - to - with the battery on all four speakers for a uniform test.

you can even check it without opening the cab.

plug a speaker cable in...touch the 9volt battery + to the tip of the cable plug and hold the battery so you can also touch the battery - minus to the cable plug. that way, you can just be in front of your cabinets and watch the speakers move, if you can see through the grill cloth.

i was gonna just raise a question too....are both your speaker cables the same type? same length? quality? etc.

i've had some shitty cables really make my sound shitty.

i would guess that your speakers are out of phase...all of them either need to push out or push in when you do the battery test.

there are a few vids on youtube to show how to test a speaker for phase/proper wiring.

google the rrest...its easy to fix!