Hook Up This Cabinet Correctly:

Inspector #20

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DSL40C has (1) output for 16ohm internal speaker and (2) outputs for 8ohm external cabinets. (2 red Jack's right of metal pancake)

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We know that you should unplug internal speaker to drive a cabinet..

Panel reads "8 ohms stereo - 4 ohms mono."

However...would I run one cable only to this cabinet, or two???

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I've pushed this hard at an outdoor venue, in blowing sand and heat, driving it with a Line 6 HD-75, but never pushed it hard with a tube amp and I want to make sure everything is right.

I don't want to damage an amp by running it flat-out with an impedance issue.

Thoughts????
 
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I been looking at the wiring diagram this morning.

The "tone shift" switch setup looks very strange. The manual sez it offers a mid scoop??? Funny that I dont hear that and I run with tone shift in (on) all the time because it just sounds fuller.

The first two poles in this circuit make a little sense, but the 3rd is confusing.

DSL40C OT wiring.jpg

DSL40C tone stack2.JPG

SW4A 470pf -> 235pF treble capacitor
SW4B 33k -> 99k slope resistor
SW4C .022uF -> .011uF mid capacitor

Am I looking at this correctly???

I haven't opened up this new DSL40C I just got from Mitch, but I'm assuming it hasn't been "clipped" as it sounds fairly normal.
 
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You went through this about six weeks ago...I still have the picture of the manual page...see “8&9”
View attachment 28374
Short answer you can connect to only one of the top/stereo jacks...either left, or right.

Maybe I should check this cabinet and be sure that the top Jack's are indeed 8 ohms and it hasn't been rewired somewhere along the way...

So, let me make sure I get this right. The presence of (2) 8ohm Jack's is insignificant as they are totally independent of each other.

1 cabinet - 1 jack ---- 2 cabinets - 2 jacks.

Why did i think that plugging into only one of the 8 ohm stereo would run only one pair of the (4) cabinet speakers????
 
You went through this about six weeks ago...I still have the picture of the manual page...see “8&9”
View attachment 28374
Short answer you can connect to only one of the top/stereo jacks...either left, or right.

Long answer, Plug your cord in like DON said. Test each jack with guitar cord and your multimeter. In each position, plug in your cord and then take one lead on the tip + the other on the shaft and read the ohms to verify all 4. Then do as Don says when the speaker impedence is verified as the same as marked on the cab.
 
Long answer, Plug your cord in like DON said. Test each jack with guitar cord and your multimeter. In each position, plug in your cord and then take one lead on the tip + the other on the shaft and read the ohms to verify all 4. Then do as Don says when the speaker impedence is verified as the same as marked on the cab.

Thanks, Chili...I'm a real bonehead in this area. That helps!!!!
 
Maybe I should check this cabinet and be sure that the top Jack's are indeed 8 ohms and it hasn't been rewired somewhere along the way...

So, let me make sure I get this right. The presence of (2) 8ohm Jack's is insignificant as they are totally independent of each other.

1 cabinet - 1 jack ---- 2 cabinets - 2 jacks.

Why did i think that plugging into only one of the 8 ohm stereo would run only one pair of the (4) cabinet speakers????


HAHA Robert, I was typing too slowly and u beat me to it
 
Robert, One reason you get the idea in some instances some 4x12 cabs do function where only 2 speakers work in one position and if switched to another, the other side 2 speakers function, is in cabs like my Marshal 1960A this is the case.


4x12 Mono/Stereo Switching Facilities (1960A, 1960B, 1960AV & 1960BV). To ensure maximum flexibility, four of our 4 x 12 cabinets boast a Mono/Stereo switching system on the back.When ‘Stereo’ mode is selected, the cabinet is split into two 8 Ohm ‘halves’ for use with a stereo power amp (e.g.: EL34 100/100, EL34 50/50, EL84 20/20, 8008 or VS 120/120) such as used in a rack system. When ‘Mono’ isselected you are offered two different impedance inputs (4 Ohms or 16 Ohms) from which to choose. Always ensure you select the correct one to match the impedance of your amplifier and NEVERuse both inputs at the sametime when the cabinet is in ‘Mono’ mode.1) Mono/Stereo Selection Switch.Selects either Stereo or Mono operation mode.2) Right* input


When switch (1) is set to:i) Stereo, this provides connection to the right* side pair of speakers.Rated at 8 Ohms.ii) Mono, this provides connection to all four speakers. Rated at 4 Ohms.3) Left* InputWhen switch (1) is set to:i) Stereo, this provides connection to the left* side pair of speakers. Rated at 8 Ohms. ii) Mono, this provides connection to all four speakers. Rated at 16 Ohms.*Note: No, we're not insane here! ‘Right’ & ‘Left’ here refers to the two stereo sides of the cabinet as seen (and heard!) when facing the front of the cab.

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Confusing!!!!!

It can be confusing,,,,,,,,,,,,, That is why I only use 16 ohm setting on my Amps that have 4/8/16 switchable settings, Then I run cab with switch in MONO over to the left, and make sure cab is 16 ohm with the Multimeter and cable. Then I only plug into the RIGHT side jack on cab. I put tape over the left jack so neither I nor anyone else can accidentally run 16 ohm amp through the cab set in 4 ohm setting.
 
I apologize...I didn't bookmark it and then couldn't find the conversation!!!!!

Thank you, Don@@@!!!!!
No apologies necessary.....here it is....
I’m in at post #36 & 37 with the manual pic.
 
View attachment 28375

View attachment 28376

SW4A 470pf -> 235pF treble capacitor
SW4B 33k -> 99k slope resistor
SW4C .022uF -> .011uF mid capacitor

Am I looking at this correctly???

Yes, you are looking at this correctly. In the "normal" switch position you have ;(SW4A) 470pf treble (& upper mid) cap, (SW4B) 33k "slope" resistance
(SW4C) 0.022uf mid cap
In the "mid scooped" switch position you have;
(SW4A) 235pf treble cap (let's less upper mids through).
(SW4B) 99k slope resistance (greater seperation of the treble frequencies & mid/bass frequencies.
(SW4C) 0.011uf mid cap (let's less lower mids through).

It's a pity the Jackson cab only offers
Stereo, 2 X 8 ohms, &
Mono, 1 X 4 ohms
& doesn't have the mono 1 X 16 ohm option like the Marshall cabs do, as you can only use two speakers at 8 ohms leaving two speakers unused.
I would check the impedance of the speakers used in the cab. If it is fitted with 16 ohm speakers it would be possible to fit the Marshall Stereo/Mono Jack Plate that Chilli showed earlier, thus allowing the Mono 16 ohm option (all 4 speakers used). The genuine Marshall part No. for this Jack Plate Stereo/Mono Switch is
M-196X-50-01.
It is available from amprepairparts.com,
Part #JP-800.
Hope this helps. Cheers
 
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