Guitar cab wiring question

[thinskin57]

i just added an iso-booth to my studio. what i'd like to do is keep my fender supersonic combo in the control room while i track (so i can make tonal adjustments), and have it feed my tremoverb combo's two (nicely broken in) speakers. being a combo, my tverb's speaker wires are wired to a 1/4" male speaker jack that normally goes to the chasis. my question is this- is it safe to connect a speaker cable from my supersonic to the tverb's speaker jack via a female/female 1/4" coupler? i'm wondering if it would create some kind of impedance issue or not.

 

[FXR]

As long as it's a good quality clean set of connectors, it should be fine.

 

[RR]

So basically you are using the TVerb's combo as an external cabinet I assume[?].

I assuming the TVerb's speakers are 16 ohms wired in parallel[?] [ Assuming they're Celestion Vintage 30s ]. So that's a total of 8 ohms [Tverb combo speaker impedance].

Is the SuperSonic Pro plugged into its own speaker combo as well? In other words is the SuperSonic is running both its own speaker and the TVerb's speakers?

Either case, so long you input in the proper impedance of the Supersonic's output jack you should be fine.

 

[94Tremoverb]

No, it is NOT always safe to use a standard typical female-to-female coupler. They are designed for signal-level applications, and the way they are constructed means that they will not always handle speaker-level current. The tip connection is usually riveted together in the middle and this can make a bad contact or even burn out if it develops significant resistance. Potentially very bad for tube amps.

What you need is to make a long speaker extension cable with a Neutrik locking 1/4" line jack on one end.

 

[FXR]

Well I stand corrected then. Looming in the back of my head was resistance and I even deleted a disclaimer sentence about impedance vs. resistance and if a low quality connection would heat up.

 

[94Tremoverb]

I did actually manage to make it happen once, which is why I don't like them - I was running some very long cables for PA in a huge tent (not a proper gig, just speech, some singing and acoustic music, with a 120W amp and four ancient 4x12" column speakers in the corners of the tent!), and used several of those couplers to join up all the speaker cables I had, so they would reach. One of them started cutting out, and being inquisitive I afterwards cut open the connector and found that the unbelievably crap little hollow brass rivet in the middle (which was probably never tight in the first place) had basically sparked itself away until it was only just making an intermittent contact. The power that did it was pretty low too, no more than 30W into 16 ohms, so well within the range of a guitar amp.

 

[thinskin57]

So basically you are using the TVerb's combo as an external cabinet I assume[?].

I assuming the TVerb's speakers are 16 ohms wired in parallel[?] [ Assuming they're Celestion Vintage 30s ]. So that's a total of 8 ohms [Tverb combo speaker impedance].

Is the SuperSonic Pro plugged into its own speaker combo as well? In other words is the SuperSonic is running both its own speaker and the TVerb's speakers?

Either case, so long you input in the proper impedance of the Supersonic's output jack you should be fine.

exactly. i'm using the tverb as a "cabinet" only. i would not be using the supersonic's internal speaker. it would be unplugged. essentially i would be using it as a head. the tverb is wired for 8 Ohm which is convenient considering the speaker out on the SS is the same impedance.

 

[thinskin57]

No, it is NOT always safe to use a standard typical female-to-female coupler. They are designed for signal-level applications, and the way they are constructed means that they will not always handle speaker-level current. The tip connection is usually riveted together in the middle and this can make a bad contact or even burn out if it develops significant resistance. Potentially very bad for tube amps.

What you need is to make a long speaker extension cable with a Neutrik locking 1/4" line jack on one end.

as always 94Tremoverb- THANKS! you confirmed my suspicion. will have to do some online searching for the "locking" neutrick thingamajig. not familiar. at what point does it lock? maybe the easiest thing would be to buy a regular 1/4" to 1/4" speaker cable, cut a jack off one end and attach the clip style connectors that slide onto the speaker contacts? maybe not?

 

[94Tremoverb]

as always 94Tremoverb- THANKS! you confirmed my suspicion. will have to do some online searching for the "locking" neutrick thingamajig. not familiar. at what point does it lock? maybe the easiest thing would be to buy a regular 1/4" to 1/4" speaker cable, cut a jack off one end and attach the clip style connectors that slide onto the speaker contacts? maybe not?

No, push-connectors are crap too! I've cut off so many of those and soldered the wires I have no idea how many hundreds any more (literally). They are an occasional source of unreliability as well.

Google "neutrik locking 1/4" line socket". Here's one on amazon: http://www.amazon.co.uk/Neutrik-NJ3FC6-Locking-Female-Socket/dp/B001C869KO

It locks in the sense that you can't pull the plug out without pressing the red button.

 

[thinskin57]

as always 94Tremoverb- THANKS! you confirmed my suspicion. will have to do some online searching for the "locking" neutrick thingamajig. not familiar. at what point does it lock? maybe the easiest thing would be to buy a regular 1/4" to 1/4" speaker cable, cut a jack off one end and attach the clip style connectors that slide onto the speaker contacts? maybe not?

No, push-connectors are crap too! I've cut off so many of those and soldered the wires I have no idea how many hundreds any more (literally). They are an occasional source of unreliability as well.

Google "neutrik locking 1/4" line socket". Here's one on amazon: http://www.amazon.co.uk/Neutrik-NJ3FC6-Locking-Female-Socket/dp/B001C869KO

It locks in the sense that you can't pull the plug out without pressing the red button.

ahhh, saw the pic in the link you sent. now i see what you meant. i'll be ordering one of those. btw- i had already removed the push-ons from the prosonic and soldered them on. the mesa, as you know, comes that way stock. kinda lame that fender still uses the push-on connectors. thanks again '94!

 

[94Tremoverb]

btw- i had already removed the push-ons from the prosonic and soldered them on. the mesa, as you know, comes that way stock. kinda lame that fender still uses the push-on connectors.

Almost all amp companies below the 'boutique' level do now - it's nice to see Mesa still cares enough to do it properly. Fender actually started as long ago as the 1960s.

Push-connectors are cheap and quick - they probably save a few cent's worth of labor time by using them - and do at least make swapping speakers easy for people who can't solder - but they do definitely cause reliability trouble. It's not just the contact between the clip and the terminal that can come loose, the clip itself is just crimped onto the wire and corrosion can get in here too when they get old.

I even think they can affect the tone, when they build up a bit of resistance. I know that sounds hard to believe and cork-sniffing, but I've noticed a subtle change on a lot of occasions when I've removed them, and every now and then quite a big one. They also cause crackling and cutting-out in non-speaker circuits too - modern amps are full of the **** things. (As is my metal-scrap box! )

 

[thinskin57]

agreed. it makes me wonder if the clips can cause impedance issues, given that the signal is being passed along a cable of a given thickness and then suddenly is reduced to such small "tangent" (for lack of a better word) contacts at the terminals. while i've got your ear, it's o.k. that that Neutrik plug is stereo, right?

 

[94Tremoverb]

agreed. it makes me wonder if the clips can cause impedance issues, given that the signal is being passed along a cable of a given thickness and then suddenly is reduced to such small "tangent" (for lack of a better word) contacts at the terminals.

Exactly, which is why I genuinely think they can affect the tone. Maybe not really when they're brand new and the metal is clean and shiny, but add a little oxidation both there and where the wires are crimped into the clip and who knows what resistance there is.

it's o.k. that that Neutrik plug is stereo, right?

Yes. You can either ignore the ring contact - or better, connect it to ground, which doubles the reliability of the connection. (I would always do this.)


(Ignore the following if math is not your thing!

Technically, it *squares* the probability of failure of the ground contact, because it then requires *both* to fail at once for the signal path to be interrupted - which is a multiplying function - and since the failure probability is small anyway, it then reduces to insignificant. eg, if the probability of failure of either contact is 1%, the total when you have two is .01^2, ie .0001, 1% of 1% , or so close to zero that it no longer matters. OK, you still have the tip contact to deal with, but that's now the only one, and since a failure in *either* the tip or ground connections can interrupt the signal path - hence is an additive function - by very nearly removing one of these you do therefore almost exactly halve the overall failure probability.

Your normal service will now be resumed.)

 

[fluff191]

(Ignore the following if math is not your thing!

Technically, it *squares* the probability of failure of the ground contact, because it then requires *both* to fail at once for the signal path to be interrupted - which is a multiplying function - and since the failure probability is small anyway, it then reduces to insignificant. eg, if the probability of failure of either contact is 1%, the total when you have two is .01^2, ie .0001, 1% of 1% , or so close to zero that it no longer matters. OK, you still have the tip contact to deal with, but that's now the only one, and since a failure in *either* the tip or ground connections can interrupt the signal path - hence is an additive function - by very nearly removing one of these you do therefore almost exactly halve the overall failure probability.

Your normal service will now be resumed.)

:shock:

Guess math isn't my thing.

 

[94Tremoverb]

Just posted that to show that the three years I was at college were not entirely spent on sex, drugs and rock'n'roll .

 

[RR]

94Tremoverb, just for that, I have a gourmet with 10 gauge wires coming out of what used to be the output speaker jack. So every gig, I hardwire (solder) to the speaker's terminal. Yes, its a hassle removing all those screws from my 4x12" but chordless drill sure comes in handy.

By the way, if the speaker output jack wasn't so small, I would have used my car battery jumper cables between the output transformer and the speaker terminal. :twisted:

[ edit, 94Tremoverb you know I'm kidding. :wink: ]

 

[MrMarkIII]

I prefer my gourmet grommets with a light bearnaise sauce.

 

[RR]

Thanks MrMarkIII :lol:

I misspelled that word, and used the right click and randomly selected which looked correct.

Now that you said that, I'm going to have lunch now (Pacific Time Zone).

 

[94Tremoverb]

94Tremoverb, just for that, I have a gourmet with 10 gauge wires coming out of what used to be the output speaker jack. So every gig, I hardwire (solder) to the speaker's terminal. Yes, its a hassle removing all those screws from my 4x12" but chordless drill sure comes in handy.

By the way, if the speaker output jack wasn't so small, I would have used my car battery jumper cables between the output transformer and the speaker terminal. :twisted:

[ edit, 94Tremoverb you know I'm kidding. :wink: ]

Lol

It is funny, isn't it - how many folks insist on using speaker cords made from the mooring cables from an aircraft carrier, but forget that once it gets into the cabinet it often passes through those pish-connectors*, or on many modern cabs, PCBs at the jack plate, let alone the near point contacts between a 1/4" jack and the plug. Once you get below 'reasonable', the resistance (or in fact any other characteristics) of the speaker cord are completely irrelevant. Anything thicker than lamp cord is just fine.

*That is not a typo.


By the way, is a chordless drill one that can only play solos?