Something is wrong, my 1x12 cab sounds enormous and alive compared to my 2x12 - check my wiring...

Billy1234

Member
Messages
157
I am transitioning away from Fender amps after forever with them and now have a used JTM45 Ceriatone that arrived last week. I kept my 112 Avatar traditional open back cab just in case I needed it down the road but I also bought a Sourmash 2061cx cab closed back with option for partial closed used to pair with the JTM45 which arrived with two et65's in it. I popped those out as soon as it arrived and put in two Scumback M75 PVC's (I used to run just one 8 ohm M75 PVC in the Avatar 112 and it sounded fantastic). I put one of the ET65's in my old Avatar 112 cab. So I'm playing around with the Ceria JTM45 and it's sounding kind of sterile. I can't quite place my finger on it, but it's just not working for me. I'm doing some final testing today and seriously thinking of popping it right on Reverb and just being happy with the bassbreaker 15 head. I mean, the cleans are good and it's clean headroom is ridiculous for my needs but something aint working with the sound and oddly enough, the bass really isn't that heavy to my ears, I have it cranked to noon and then had it on full and it thickened up the tone some but I mean, it wasn't that big of a bottom end like everyone talked about. I checked my ohm switch on the JTM, everything is correct. I tried going partial closed back, full closed back and even tried moving the closed back section with the top open, bottom open etc. I tried reversing the wiring on the second speaker in the 212 sourmash, that made it sound incredibly thin and horrible so my wiring was correct in order to have my two 8ohm M75's be wired to 16 ohm. Finally for ***** and giggles, I tried plugging the JTM45 into the 112 avatar cab with et65's, switched the ohms back to 8 on the JTM45 and.... holy ****, there's my tone! HUGE bottom end, I had to turn the bass to zero and it's still nice and full, everything felt alive, it felt proper. Oh my god, the Ceriatone JTM45 through this 112 Avatar was so amazing. So... I know the M75's sound awesome in the Avatar 112, it can't be them... so I'm left deciding:

1. Is the wiring incorrect in the sourmash cab? When I received it, they obviously had created their own wiring inside as it's really thick speaker cable they're using where as the avatar shipped with much thinner black wire - I've attached pics.
2. Is this sourmash cab the worst cab ever made before? It's certainly beautiful on the outside and feels sturdy.
3. Is my Avatar 112 cab the greatest ever built :)

Ideas?

ET65 wiring I received:


My M75 PVC:
 

Scumback Speakers

Platinum Supporting Member
Messages
10,864
I can't make out the wiring as well as I'd like, but you need to check it from the jack to the 1st speaker then to the second to make sure the jack isn't wired out of phase by accident on the 2x12. I'm guessing it's series wiring with two 8 ohm speakers to a 16 ohm total load, so use the series 2x12 wiring at this link, and trace the wires back to the jack to make sure.

http://www.scumbackspeakers.com/wire.html

The other option you don't want to hear is that your amp may not sound right to you on the 16 ohm tap if your speakers are wired correctly. Then you get into the potential issue of it sounding good on 8 ohms but not 16.

Good luck!
 

C-4

Member
Messages
13,601
Are the valves in your Ceritone all functioning properly?
If your 1x12 sounds good with the JTM 45, it is possibly the 2x12 causing you problems. Are the speakers in the 2x12 broken in already? Wired correctly?
 

frthib

Member
Messages
1,467
Just a guess, each speaker is receiving half the power (I think) the amp generate.. Maybe this neutered power isn't enough to place the speaker in it's spot where it open up.. I have 2 1x12 with the same speaker and I have to raise volume to have the same "type" of sound I have with just 1 1x12. At that volume, it's quite loud
 

calfzilla

Cynical Hack
Messages
3,873
I can't make out the wiring as well as I'd like, but you need to check it from the jack to the 1st speaker then to the second to make sure the jack isn't wired out of phase by accident on the 2x12. I'm guessing it's series wiring with two 8 ohm speakers to a 16 ohm total load, so use the series 2x12 wiring at this link, and trace the wires back to the jack to make sure.

http://www.scumbackspeakers.com/wire.html

The other option you don't want to hear is that your amp may not sound right to you on the 16 ohm tap if your speakers are wired correctly. Then you get into the potential issue of it sounding good on 8 ohms but not 16.

Good luck!
He's got the speakers wired up correctly for series (it is quite tough to follow that twisted pair on screen). @Billy1234 can you snap a picture of the input wired to the first speaker?
 

Grimace

Member
Messages
675
After you check all the above, perhaps try a single speaker in the 2x12 at 8 ohms, might address the issue Scumback raised.
 

Billy1234

Member
Messages
157
Sorry guys, here's some better pics with better lighting and a better shot of the whole setup:









 

Papanate

Member
Messages
19,859
Are the speakers 8 ohm or 16 ohm each? If that top cabinet has 2 x 16 ohm speakers in
it and it is wired in series (which I think it is from the picture) then you are running 32
ohms which would certainly muck up the sound. As I see in your pictures they are 8
ohms each so the cabinet is running at 16 ohms - do you have the amp output set to 16
ohms?

 

Billy1234

Member
Messages
157
Are the speakers 8 ohm or 16 ohm each? If that top cabinet has 2 x 16 ohm speakers in
it and it is wired in series (which I think it is from the picture) then you are running 32
ohms which would certainly muck up the sound. As I see in your pictures they are 8
ohms each so the cabinet is running at 16 ohms - do you have the amp output set to 16
ohms?

Yup, I have the JTM running at 16ohms, I'm positive. I made sure to switch it to 8 ohms when trying out the 112 to see if that was the issue...
 

Scumback Speakers

Platinum Supporting Member
Messages
10,864
You got me. I will say that the red & black 16 gauge wire I use is a lot easier to track when you suspect wiring issues! LOL

Here's my 2x12 wiring pic. Use the series wiring on the bottom. Not sure, but I think you have the wires switched at the jack, resulting in an out of phase setup which will make it sound thin.

 
Last edited:

Papanate

Member
Messages
19,859
Yup, I have the JTM running at 16ohms, I'm positive. I made sure to switch it to 8 ohms when trying out the 112 to see if that was the issue...

I would say then if the speakers are wired correctly - then you have damaged them somehow.
 

bdm

Silver Supporting Member
Messages
3,338
I've had similar reactions when comparing various cabs over the years.

Generally, 1x12 and 4x12 cabs sound better to my ears than 2x12s. I can't quite put my finger on what it is.
 

Billy1234

Member
Messages
157
I've had similar reactions when comparing various cabs over the years.

Generally, 1x12 and 4x12 cabs sound better to my ears than 2x12s. I can't quite put my finger on what it is.
This really isn't a taste thing. This 112 is blowing my 212 out of the water. My JTM45 has very thin bass when using the 212 while the 112 is SOOO much bass like everyone talks about with the JTM. The sound is MUCH more lively, like night and day. It's really not a subjective thing, it's just instantly leaps and bounds better.

I will say, the sourmash cab's mounting holes were a little wacky, like they didn't line up perfectly to the Scumbacks, it took a good deal more finagling to get them to mount vs the Avatar cab - but I still proceeded with a ton of caution and only used hand tightening as recommended and didn't over tighten. That's the only other thing I could think of that was weird about the cab. I guess the next things to try next will be:

1. Check and see if the JTM45 sounds just as good or very close running 16 ohms into the 112 8 ohm speaker - this is just to make sure there's not an issue with the Ceria JTM45 ohm switch.

2. Try both scumbacks individually in the Avatar 112 and see if I get similar results. If they sound great in the 112, then I know the sourmash cab has an issue somehow. Either the cab is built oddly, or the weirdly lined up holes aren't letting the Scumbacks get a good seal to provide the response they're supposed to. I know the Scumbacks blew me away when I had them in the 112 with my Fender Bassbeaker 15, so I would expect similar performance and obviously even more with a handwired JTM45.
 

InAbsentia

Member
Messages
1,519
You got me. I will say that the red & black 16 gauge wire I use is a lot easier to track when you suspect wiring issues! LOL

Here's my 2x12 wiring pic. Use the series wiring on the bottom. Not sure, but I think you have the wires switched at the jack, resulting in an out of phase setup which will make it sound thin.
The only problem, in the original OP he stated he switched one of the wires in the 212 and it was incredibly thin and sounded awful, so I don't think they are out of phase in the 212.
 

Billy1234

Member
Messages
157
I thought that a jack doesn't have positive and negative terminals - it's dependent upon how you wire the speakers ie. either terminal could be positive or negative depending on how you connect it to the speaker terminals? Unfortunately, my jack had the speaker wire soldered on but the speaker wire is clearly not from sourmash so if they did indeed hook up their terminals backwards at the jack, this could be the issue perhaps? Again, it's not a taste subjective sound change, the 112 is blowing the ****ing doors off my 212 right now. It's very strange - the sound coming out of the 112 with a single et65 sitting next to the sourmash 212 makes your mind think it has to be the beautiful 212 you're hearing, there's so much more depth, fullness, bass. Again though, my m75 pvc's blew my mind when they were in the 112, so that's what I'll be testing tomorrow am (I have the house to myself in the morning as I work from home so can't do any more tests today). Very strange.
 

tenchijin2

Member
Messages
3,031
It would be really easy to check if there are any phase issues by just swapping the wires on one of the speakers to see.
 

Billy1234

Member
Messages
157
It would be really easy to check if there are any phase issues by just swapping the wires on one of the speakers to see.
Yup, already did that. At least I did a few days ago when I first noticed that this 212 didn't sound as good as I thought it should have. I'll try this again tomorrow AM just to make sure.

I will also add trying a single scumback in the sourmash at 8 ohms. That would eliminate a lot of possible problems with wiring and speaker seating in the sourmash.

Thanks all for walking me through this. This used to happen to me with computer upgrades - if you change out too many parts and software starts acting weird, it's much more difficult to trace where the issue is VS. installing one new part at a time and checking it's function as you go. Introducing a new amp and a used cab while also swapping speakers in and out of it - perhaps too many moving parts at once.
 




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