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Ok...tired subject, but I need advice.

#101
For the guys saying turn down the guitars, they don't play wide open all the time...it was just a show with minimal foh... vocals, snare, kick... Not a common thing.... Though I'd like to have the ability to keep up in my arsenal... And when guitars are in foh, the stage volume is down a bit too... Just because you can make ears bleed doesn't mandate you to....
 
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#103
Man, I'm having a tough time following this thread...

Did you change speakers in the 212??? Did you measure the individual drivers to be sure you have what you think you have?
 
#105
agedhorse said:
Man, I'm having a tough time following this thread...

Did you change speakers in the 212??? Did you measure the individual drivers to be sure you have what you think you have?
Click to expand...
I built the 2x12 with the sicas
Reloaded the 4x12 with eminence
Both cab's are supposed to be 8 ohms... I'm going to test them this weekend and go from there....also I'm a/b ing my cab's and other cabs... I still haven't gotten a chance to test my new eq settings on the full stack, but it seems to help tremendously on the 2x12, which is at my house currently.
 
#106
Your measurement on the 212's DC resistance indicates that it is not 8 ohms. You need to sort this out before you damage something.
 
#107
dukey donkey said:
I built the 2x12 with the sicas
Reloaded the 4x12 with eminence
Both cab's are supposed to be 8 ohms... I'm going to test them this weekend and go from there....also I'm a/b ing my cab's and other cabs... I still haven't gotten a chance to test my new eq settings on the full stack, but it seems to help tremendously on the 2x12, which is at my house currently.
Click to expand...
You can't wire four 4-ohm speakers to an 8-ohm impedance. Your options are 1 ohm (parallel), 4 ohms (series-parallel), or 16 ohms (series).

Maybe it's time for a little tough love. First, you don't even know how to figure out the impedance of a cab based on the wiring configuration of the speakers. This is a classic case of popping some random drivers into a cab of some random volume and porting (or lack of porting) and hoping you get a cab that sounds good and can produce optimal volume. The chances of that happening are practically nil.

There is considerable science behind cabinet design and construction. There are countless threads here by people wanting to do exactly what you've done regardless of repeatedly being advised it's a waste of time, materials and, hence, money. They go ahead and build it and can't figure out why their cab doesn't sound like that greenboy/Mesa/Bergantino/Ampeg they heard at someone else's show. "How come my 412 doesn't sound like that guy's? It's got four 12s in it."

Save up some coin and buy a professionally designed cab or cabs from a reputable company. Read some threads and see whose products get consistently good reviews - there are plenty of them out there. If you want to sound good, don't throw your tone to chance - you'll have better luck at winning the Powerball.
 
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#108
@dukey donkey @astack @agedhorse:
Astack is right in pointing out the DC resistance in the parameters of the driver used in the 212 cab, as reported in the spec sheet posted in post #40, points to the driver being an 8-ohm one, in spite of the same spec sheet calling it a 4-ohmer. I've followed the breadcrumbs on the 'net. There's a couple American websites selling a driver called a Sica PL12B25S:
Link Removed
post #40
The latter's wording "available in 4 ohm impedance" is usually short for "this one is 8-ohm, a 4-ohm version can be ordered, but the following T/S parameters refer to the 8-ohm one", and is at odds with the sheet flat out saying it's 4 ohms further below.
Now, besides the fact that there's no trace of a "PL12B25S" in official Sica literature (which wouldn't be suspicious in and of itself if it were a discontinued product) and almost anywhere outside that handful of US sites (or forum posts by US people looking into the driver and asking for opinions) for that matter, makes me think someone at Sica's US distribution mixed info up.

The woofer's real identity is the following:
https://www.toutlehautparleur.com/media/catalog/product/datasheet/sica/Z007831.pdf
It's actually a Sica 12 BS 2,5 PL - 8Ω, a.k.a. Z007831 (all Sicas and Jensens have a Z... part designation code).
Same exact T/S parameters, so it's definitely the one.
[For the record, the true 4-ohm version is this one, the Z007832. The link also has a useful guide to Sica letter codes -in our case: 12-inch, bass, smooth, 2.5-inch voice coil (in numbers we use commas instead of dots and v.v.), Premium Lite series (aluminium basket, neodymium magnet), 8-ohms nominal impedance.]

If you (the OP) wired the Sicas in series to get what you believed to be an 8-ohm cab, what you got is actually a 16-ohm cabinet (of decent power sensitivity but low voltage sensitivity). Adding it to the 412 (loaded with woof-capable but low-efficiency LFA Eminences as said), the total impedence of the stack is 5.33... ohms. Just another element to consider (I'd also subscribe to EQ being the main culprit). At least the wiring is "correct" as far as power distribution (again, if and only if the 2x12 is in series and the 4x12 in series-parallel).

EDIT- The above assumes the T/S parameters, minus the stated impedance, were correct for the drivers you actually received. Can you pull one of the Sicas out and read any labels in the back it may have?
 
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#112
Your random 2 cabs are probably fighting each other. If you like the reloaded peavey cab in terms of sound and overall volume, but just need more volume to compete with overcompensating guitarists, just get another tvx and load it with the same drivers. At any rate if the peavey/eminence cab is 8 ohms and the sica cab is 16, you're only getting marginally more power from the amp from the impedence drop, but not enough to give the peavey more power than it was probably already getting. So MAYBE the sica cab is adding like 1 or 2 db to your overall SPL at a given master volume position, but then it could very well have phase response conflicts with the peavey cab that wipe those out and even go farther, and/or ust provide a very uneven response as you go up and down the frequency spectrum. This could very well result in the lack of balls you are perceiving. You should be louder with your new found EQ settings, but "balls" come into play when a well designed system is working at optimum efficiency with no funny cancellations or reinforcements. That's when you get that effortless, bottomless push, where it doesn't so much sound "loud", it just sounds BIG. 2 of those peavey cabs with the same deltas run by the subway should do that if those drivers are reasonably suited to that cab.

As a sort of interim if you can't afford or find another peavey cab, you could try the same deltas in the homemade 2x12. Since you already have the ones in the peavey, if you don't mind experimenting, you could just swap a pair over for a bit, wired at 4 ohms (just go easy on the volume). Then, if they sound good and respond well to that cab, buy another pair and wire the 2x12 at 16 ohms for use with the 4x12 so all the drivers are getting the same power. Sell the sicas to hopefully defray the cost of the deltas. And then, when you DO find another peavey, you're already halfway to having enough drivers for it.
 
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#116
Got a reading of less than 1 ohm so something is awry... I'm going to start there and rewire the speakers... I know a lot of folks in this post have made comments referring to me not listening or not explaining anything but I've tried to do all I could to satisfy each and every one of you... As a matter of fact I'm the one that hasn't been listened to because I repeatedly said I was going to test as soon as I could with a multimeter and then go from there if we wiring the cabinet doesn't help I'm also testing some other cabinets out this weekend to see if that helps... patience my peers... Everyone's so pushy LOL
 
#117
Hey Dukey, another suggestion. Hope you don't take it the wrong way.

Did you short the leads of your DVM to see what reading you get before measuring the cab?
Short, get a reading, subtract that from your speaker measurement. And account for the reading being lower than nominal impedance because you are measuring DC resistance, not impedance.
If you are using a VOM, can you zero out the reading with the leads shorted first? If not, you meter might need a new battery.

These are all things that can throw off your readings.

Also, if you don't mind my saying, once you have the cab open, it might be helpful to measure each speaker individually while they are disconnected from each other.
 
#118
dukey donkey said:
Got a reading of less than 1 ohm so something is awry... I'm going to start there and rewire the speakers... I know a lot of folks in this post have made comments referring to me not listening or not explaining anything but I've tried to do all I could to satisfy each and every one of you... As a matter of fact I'm the one that hasn't been listened to because I repeatedly said I was going to test as soon as I could with a multimeter and then go from there if we wiring the cabinet doesn't help I'm also testing some other cabinets out this weekend to see if that helps... patience my peers... Everyone's so pushy LOL
Click to expand...
If you are really reading 1 ohm on each of your drivers, do not continue on until you figure out if the measurements are bad, or you have defective drivers, or you are measuring incorrectly.

Something is very wrong, have you checked the battery in your meter? You may need to use a different meter if your's is defective or inappropriate for the task of measuring low resistances.

If there is something wrong with your drivers, it's not likely that damaging your amp would be covered under warranty, so you need to be sure of what you are doing before plugging in and turning on.

You might also consider that some of the folks here are offering you some very good information. If you become disrespectful to their help, that's a quick way to be left to yourself with no further help.
 
#119
amp+ speak1+, speak1- speak2+, speak2- speak3-, speak3- speak4+, speak4- amp-

Should be series parallel so your cab impedance is the same as each speaker individually. Check each speaker before rewiring as 1 may be shorted and it's not a wiring issue.

Someone check my wiring from above. I'm coming in from yard work with a bad ticker for short breaks.
 
#120
dukey donkey said:
As a matter of fact I'm the one that hasn't been listened to because I repeatedly said I was going to test as soon as I could with a multimeter and then go from there if we wiring the cabinet doesn't help I'm also testing some other cabinets out this weekend to see if that helps... patience my peers... Everyone's so pushy LOL
Click to expand...
Tell us about the box once we know what is wrong with the speakers or wiring, the 1 ohm thing :D
 

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