# 50' Cable From Head To Cab?



## player99 (Sep 5, 2019)

I am setting up a separate recording space for my amp cabs, and will have the heads in another area of the house by my recording equipment. So I will need about 50' of speaker wire to go from the heads to the cabs.

A site that sells the wire suggests on longer runs " *(**)If you run cable lengths over fifty feet, we recommend you to use 14 gauge or 12 gauge.(12 gauge is recommended)* "

Is this good advice for amps?

I am looking at ordering this 100' roll:



https://www.primecables.ca/p-358019-cab-13707-all-nimbus-series-12awg-2-conductor-cmp-rated-speaker-wire-monoprice#sku366754



Any advice? 
Is this the best cable, and a good buy? 
What about the jacks? 
Are regular jacks sufficient?


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## greco (Jul 15, 2007)

If you go with 12 gauge, I would look for the specific plugs with a larger barrel for this purpose. 
Switchcraft #285L - 1/4" Mono Straight Plug (for speaker cable)
Speak-ons would also be an excellent choice IMO.


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## player99 (Sep 5, 2019)

greco said:


> If you go with 12 gauge, I would look for the specific plugs with a larger barrel for this purpose.
> Switchcraft #285L - 1/4" Mono Straight Plug (for speaker cable)
> Speak-ons would also be an excellent choice IMO.


I have some of those I bought about 10 years ago because I thought they were cool being extra large. Now I have a use for them. Thanks for the heads up.

What speak-ons would be 1/4"?


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## player99 (Sep 5, 2019)

These are the ones here?


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## greco (Jul 15, 2007)

Yes...The ones in your pic are perfect.

Speakon are a different design of connectors but are often used for the application you are referring to.








Speakon connector - Wikipedia







en.wikipedia.org


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## player99 (Sep 5, 2019)

greco said:


> Yes...The ones in your pic are perfect.
> 
> Speakon are a different design of connectors but are often used for the application you are referring to.
> 
> ...


I get the speakons for speakers, but all my amp heads have 1/4" TS and all the amp cabs have 1/4" TS. I don't see how speakons would work here, but I think you mean speakons are used in long cable connections, just not this application?


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## nonreverb (Sep 19, 2006)

If you have the option, run the head/cab at 16 ohms to minimize the effect of line loss.


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## player99 (Sep 5, 2019)

nonreverb said:


> If you have the option, run the head/cab at 16 ohms to minimize the effect of line loss.


Can you run a head at 16 into a cab at 4 or 8 ohms?


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## nonreverb (Sep 19, 2006)

It's not ideal...8 to 8 is better than 4 to 4 though


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## Latole (Aug 11, 2020)

Cable gauge;
First, do you want to drive the cab with 100 watts amp at full volume or a 5 watts amps ?

A 16 ohms head need a 16 ohms cab.
You may not hurt the amp if you use a 8 ohms cab short time at "low "power.
I will not use a 4 ohms cab

Tu parles français sans doute ?


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## Guitar101 (Jan 19, 2011)

player99 said:


> I am setting up a separate recording space for my amp cabs, and will have the heads in another area of the house by my recording equipment. So I will need about 50' of speaker wire to go from the heads to the cabs.
> 
> A site that sells the wire suggests on longer runs " *(**)If you run cable lengths over fifty feet, we recommend you to use 14 gauge or 12 gauge.(12 gauge is recommended)* "
> 
> ...


I bought this stuff many years ago to supply my speaker cabs when we were playing large venues. Their still going strong today. I paid way more than this back then. You would need those large barrel jacks for this wire.



https://www.primecables.ca/p-313370-cab-2747-50ft-speaker-wire-12awg-enhanced-loud-oxygen-free-copper-cable-primecables


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## player99 (Sep 5, 2019)

Guitar101 said:


> I bought this stuff many years ago to supply my speaker cabs when we were playing large venues. Their still going strong today. I paid way more than this back then. You would need those large barrel jacks for this wire.
> 
> 
> 
> https://www.primecables.ca/p-313370-cab-2747-50ft-speaker-wire-12awg-enhanced-loud-oxygen-free-copper-cable-primecables


I wound up ordering this one:



https://www.primecables.ca/p-358019-cab-13707-all-nimbus-series-12awg-2-conductor-cmp-rated-speaker-wire-monoprice#sku366754


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## Latole (Aug 11, 2020)

player99 said:


> I wound up ordering this one:
> 
> 
> 
> https://www.primecables.ca/p-358019-cab-13707-all-nimbus-series-12awg-2-conductor-cmp-rated-speaker-wire-monoprice#sku366754



Ça va aller.


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## greco (Jul 15, 2007)

player99 said:


> I get the speakons for speakers, but all my amp heads have 1/4" TS and all the amp cabs have 1/4" TS. I don't see how speakons would work here, but I think you mean speakons are used in long cable connections, just not this application?


Sorry, I wasn't clear. I meant Speakon plugs and jacks would work well for the cab(s).
Of interest...Some amps do have Speakon jacks.


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## cbg1 (Mar 27, 2012)

player99 said:


> I wound up ordering this one:
> 
> 
> 
> https://www.primecables.ca/p-358019-cab-13707-all-nimbus-series-12awg-2-conductor-cmp-rated-speaker-wire-monoprice#sku366754


that wire is probably a bit pricier as it is plenum rated to be used in return air spaces.it relates to fire rating of the conductor insulation and jacket materials.
good luck with the project.


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## Paul Running (Apr 12, 2020)

Rich has the right idea. High impedance transmission, to lower current demand, much like the method that hydro transmission is accomplished.


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## Milkman (Feb 2, 2006)

I know it's probably not practical, because nobody wants to modify their heads like this, but if it was to be a permanent installation, would another option be to separate the preamp sections from the power amp sections of the amp heads?

That way you could keep the controls where you need them (close to the recording gear), send the signal to the power amp sections by low impedance (XLR) cables and keep the amp sections close to the cabs with nice short speaker wire runs.

Again, I'm not proposing that in your case. I'm just wondering if it would be a viable idea and how it would compare in terms of sound.


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## nonreverb (Sep 19, 2006)

Latole said:


> Cable gauge;
> First, do you want to drive the cab with 100 watts amp at full volume or a 5 watts amps ?
> 
> A 16 ohms head need a 16 ohms cab.
> ...


Only for solid state. Going up in impedance is what kills output transformers and tubes.
Remember some tube amps use a shorting jack on the output of their amps just for this very reason. The internal impedance and reactance of the transformers will prevent a dead short although leaving it like that with full power wouldn't be a good idea...an open on the other hand will cause fyback voltages that can kill a transformer if the volume is cranked high enough


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## nonreverb (Sep 19, 2006)

Milkman said:


> I know it's probably not practical, because nobody wants to modify their heads like this, but if it was to be a permanent installation, would another option be to separate the preamp sections from the power amp sections of the amp heads?
> 
> That way you could keep the controls where you need them (close to the recording gear), send the signal to the power amp sections by low impedance (XLR) cables and keep the amp sections close to the cabs with nice short speaker wire runs.
> 
> Again, I'm not proposing that in your case. I'm just wondering if it would be a viable idea and how it would compare in terms of sound.


The only concern I'd have regarding that is that hifgh impedance lines tend to be sensitive to noise.


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## Milkman (Feb 2, 2006)

nonreverb said:


> The only concern I'd have regarding that is that hifgh impedance lines tend to be sensitive to noise.


I'm sorry, which high impedance lines?


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## nonreverb (Sep 19, 2006)

Milkman said:


> I'm sorry, which high impedance lines?


Preamp to power amp. I don't think that would be practical. Separating the internals of the amp plus the drive signal is usually fairly high impedance as opposed to the power output which as we're discussing here, is low impedance. Low impedance XLR cables does not make the circuit low impedance.


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## player99 (Sep 5, 2019)

cbg1 said:


> that wire is probably a bit pricier as it is plenum rated to be used in return air spaces.it relates to fire rating of the conductor insulation and jacket materials.
> good luck with the project.


I wanted it to be more robust on the outside. The clear casing is not as tough. Or at least didn't appear as tough.


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## Milkman (Feb 2, 2006)

nonreverb said:


> Preamp to power amp. I don't think that would be practical. One for separating the internals of the amp plus the drive signal is usually fairly high impedance as opposed to the power output which as we're discussing here, is low impedance. Low impedance XLR cables does not make the circuit low impedance.



I see. I figured if the output (from the preamp) was XLR, it would be low impedance.

I guess I'm thinking in PA terms. 

You generally send everything from the tone shaping section (preamps) via XLR (low impedance) to the input of the power amps which you try to keep close to the speakers if possible.

Sorry to confuse things.


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## nonreverb (Sep 19, 2006)

Milkman said:


> I see. I figured if the output (from the preamp) was XLR, it would be low impedance.
> 
> I guess I'm thinking in PA terms.
> 
> ...


No problem! Tubes amps can be a PITA.


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## laristotle (Aug 29, 2019)

Came across this FB ad. $110.
Maybe he'll ship?




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## greco (Jul 15, 2007)

laristotle said:


> Came across this FB ad. $110.
> Maybe he'll ship?


In addition, they appear to be 12 gauge...nice!


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## Paul Running (Apr 12, 2020)

Someday Nicola Tesla's research into low-impedance, wireless transmission will become a reality. This would be a candidate for it's application.


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## bolero (Oct 11, 2006)

what about the 100v output on stuff like old Marshall Super PA amps?

that was specifically for really long cable runs, wasn't it?

what kind of speakers would work with that?

cranked Marshall through one of these....oh yeah baby


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## tomee2 (Feb 27, 2017)

nonreverb said:


> Only for solid state. Going up in impedance is what kills output transformers and tubes.
> Remember some tube amps use a shorting jack on the output of their amps just for this very reason. The internal impedance and reactance of the transformers will prevent a dead short although leaving it like that with full power wouldn't be a good idea...an open on the other hand will cause fyback voltages that can kill a transformer if the volume is cranked high enough


But a 16ohm cab is better to use with a 50 foot speaker cable compared to the 8 ohm cab, as resistance losses are lowered, isn't it? Set the amp at 16ohms to match the cab and you're ok, even with a tube amp, right?


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## nonreverb (Sep 19, 2006)

tomee2 said:


> But a 16ohm cab is better to use with a 50 foot speaker cable compared to the 8 ohm cab, as resistance losses are lowered, isn't it? Set the amp at 16ohms to match the cab and you're ok, even with a tube amp, right?


Indeed it is. You're trying to minimize the effect of the cable resistance due to its length.


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## Paul Running (Apr 12, 2020)

player99 said:


> I am setting up a separate recording space for my amp cabs, and will have the heads in another area of the house by my recording equipment. So I will need about 50' of speaker wire to go from the heads to the cabs.
> 
> A site that sells the wire suggests on longer runs " *(**)If you run cable lengths over fifty feet, we recommend you to use 14 gauge or 12 gauge.(12 gauge is recommended)* "
> 
> ...


If your amp has a distributed-system line out, like the vintage PA, tube amp TFMs use. Run that high-impedance line to drive a slave amp.


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## Paul Running (Apr 12, 2020)

Or, if no slave amp...a matching TFM at your cab.


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## Paul Running (Apr 12, 2020)

Better yet, use your vintage PA amp...it will probably have 70 and 100v lines out. I bet you that amp with 6 X 6L6s would sound awesome...if you have enough cabs.


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## mhammer (Nov 30, 2007)

*MEASURE the resistance of the cable!* The load that the amp sees is the sum total of the speaker impedance PLUS whatever the connecting cable adds on top of that. Normally, the distance between head and cab are short enough that we are only concerned with the cable's ability to handle the current passing through it, and not with the linear resistance added by the cable. But at the distances the OP is talking about, there can be appreciable linear resistance added between head and cab. Heck, 50ft of 18gauge might have no issues passing the current from a 50W head, but add 3-4ohms of linear resistance between head and cab.

Advice about wire gauge and plug dimensions is all well and good and sensible, but best to actually measure the linear resistance to have a better idea of what you're dealing with.


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## Granny Gremlin (Jun 3, 2016)

nonreverb said:


> If you have the option, run the head/cab at 16 ohms to minimize the effect of line loss.



Total non issue (this is amplified speaker level not line level; the power/strength of the signal trumps all noise issues and line loss). Especially with 12 gauge cable. I mean, how long do you think the cable runs are in large venues from amp to speakers ?

The suggestion to mod the amp to keep preamp close and power amp by the cab is even worse. The BEST thing to do for long cable runs is send the amplified signal on the long run; keep low level signal chains short and well sheilded, especially if unbalanced as is the case with guitar and intra-amp connections. That's litterally why pro studios have all their heads in the control room running speaker wire to the cabs in the live room. The next best thing (prob better but more of a pain) is , yes, to send a balanced loZ, (not hiZ) line from instrument to amp (e.g.use 2 passive DIs, 1 backwards at the amp end; will need a custom XLR cable or gender changer adapter for that) but then you don't have remote control. You'd need the DIs (or a transformer, or an active solution, which can be cheaper but more complex to implement) if you did this between pre and power sections too, but that's even more of a pain and ain'tnobodygottimeforthat. Also forget about resale.

OP is on the right track; he's got the wire and the jacks. Lets not complicate things unnecessarily.

@mhammer does raise a valid point, but again it is probably negligable. Doesn't hurt to check tho, and if it is more than 1-2.5 Ohms, you can use the 4 Ohm amp out into an 8 ohm cab since 4 + 3 to 5= 7 to 9 and close enuf. Remember impedance (Z) is not a constant; varies by frequency so a perfect match is pointless (see also the infamous Traynor 6x10 with 6 ohm rating; or the Fender 3x10 Bandmaster combo - neither of those blow up more than any other amp/speaker combination). Even 8 ohm out to a 1 inch wire to 8 ohm cab is gonna peak at 20 Ohms or even more at e.g. the speaker's upper resonance point (more at the lower resonance point). That's why they call amp/speaker Z ratings 'nominal,' and the speaker's DC R is (almost) always less than the nominal Z.

Take this example of a "4Ohm" speaker's Z response curve. Notice how it's only actually 4 Ohms at approx 60 and 200-some-odd Hz. Notice also how it remains +/- 3 ohms for most of the useful range of a guitar, but then it does go up significantly in the treble end (or in the bottom if playing bass); tube amps have been handling that fine for literally ever.



https://images.audiojudgement.com/2016/08/impedance-chart-explained.jpg



The speaker's reactance (voice coil is a coil, therefore inductive) is gonna be > cable DCR except in insane circumstances.


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## nonreverb (Sep 19, 2006)

Granny Gremlin said:


> Total non issue (this is amplified speaker level not line level; the power/strength of the signal trumps all noise issues and line loss). Especially with 12 gauge cable. I mean, how long do you think the cable runs are in large venues from amp to speakers ?
> 
> The suggestion to mod the amp to keep preamp close and power amp by the cab is even worse. The BEST thing to do for long cable runs is send the amplified signal on the long run; keep low level signal chains short and well sheilded, especially if unbalanced as is the case with guitar and intra-amp connections. That's litterally why pro studios have all their heads in the control room running speaker wire to the cabs in the live room. The next best thing (prob better but more of a pain) is , yes, to send a balanced loZ, (not hiZ) line from instrument to amp (e.g.use 2 passive DIs, 1 backwards at the amp end; will need a custom XLR cable or gender changer adapter for that) but then you don't have remote control. You'd need the DIs (or a transformer, or an active solution, which can be cheaper but more complex to implement) if you did this between pre and power sections too, but that's even more of a pain and ain'tnobodygottimeforthat. Also forget about resale.
> 
> ...


Why do you think 70V and 100V constant (high impedance) systems were made way back in the 50's and '60's? Also, most if not all PA's in the early days utilizing non carrier voltage systems were 16 ohms. Because they minimized line loss. You're forgetting that linear line loss is not reactance. It's a measurable constant loss along the line which as it's made longer, will insert more resistance...not reactance to the system. Remember: a 1 ohm increase along a conductor in a 4 ohm system is 25% increase in total resistance. 2 ohms is 50% regardless of reactance! Yes, reactance varies with frequency however, a 50' cable could add a significant amount of loss across the frequency range. If one has the ability to set it for 16ohms why not? It's ensuring the best transfer of power possible.
Also cable runs to large passive speakers in most large venues I've seen are a thing of the past. They're all self powered units. Why? For many reasons. One being it's far more efficient to run line level signals where line loss is negligible than running power outputs to passive speakers.


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## nonreverb (Sep 19, 2006)

"@mhammer does raise a valid point, but again it is probably negligable. Doesn't hurt to check tho, and if it is more than 1-2.5 Ohms, you can use the 4 Ohm amp out into an 8 ohm cab since 4 + 3 to 5= 7 to 9 and close enuf."

Suggesting a 100% mismatch increase plus line resistance is asking for trouble. We're not talking solid state here. Tube amp output transformers...especially dimed which is the whole premise this discussion is probably about, risk being damaged. One should thoroughly investigate all the scenarios before plugging in and blasting away.


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## mhammer (Nov 30, 2007)

In case some folks are getting lost in all of this, let me emphasize that my encouragement to measure the actual DCR of the cable is not so much for the purposes of not having the amp head blow a transformer. Rather, whatever amp settings get you the sound you want when head sits atop cab, should not change dramatically when cab moves 50ft of cable away. I was viewing it through a consistency and replicability lens rather than amp-safety lens. In terms of safety, yes it probably *is* negligible. But since the OP's goal is to create a setup for production purposes, one likely wants to know that what the cab does when it's over* here* should not be different in some way from what is does over *there* as a result of unanticipated output load changes. If one has measured the DCR of the connecting cable, and used the gauge that gets you as low a DCR over and above the speaker load as you can get, then one can at least check that off the list and safely assume that any "tonal surprises" may well stem from the positioning of the cab in the performance space, and not from the connecting cable.


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## nonreverb (Sep 19, 2006)

mhammer said:


> In case some folks are getting lost in all of this, let me emphasize that my encouragement to measure the actual DCR of the cable is not so much for the purposes of not having the amp head blow a transformer. Rather, whatever amp settings get you the sound you want when head sits atop cab, should not change dramatically when cab moves 50ft of cable away. I was viewing it through a consistency and replicability lens rather than amp-safety lens. In terms of safety, yes it probably *is* negligible. But since the OP's goal is to create a setup for production purposes, one likely wants to know that what the cab does when it's over* here* should not be different in some way from what is does over *there* as a result of unanticipated output load changes. If one has measured the DCR of the connecting cable, and used the gauge that gets you as low a DCR over and above the speaker load as you can get, then one can at least check that off the list and safely assume that any "tonal surprises" may well stem from the positioning of the cab in the performance space, and not from the connecting cable.


Agreed Mark....One thing that could be added to this is remember to measure BOTH wires. For instance, If the hot were to have 2 ohms across it's lengh, it's a pretty safe bet the ground probably does as well.


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## Granny Gremlin (Jun 3, 2016)

@nonreverb your straw man arguments (I didn't say some of the things you say I said) and seemingly (it's hard to tell on the internet) angry ranting do not make you look like you know what you're talking about or that you know how to present a succint case for your point of view (e.g. 70V systems are NOT constant impedance but constant voltage; hence being called "70V").


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## nonreverb (Sep 19, 2006)

Granny Gremlin said:


> @nonreverb your straw man arguments (I didn't say some of the things you say I said) and seemingly (it's hard to tell on the internet) angry ranting do not make you look like you know what you're talking about or that you know how to present a succint case for your point of view (e.g. 70V systems are NOT constant impedance but constant voltage; hence being called "70V").


Easy buddy....sounds like you're the one losing his sh*t here. I said 100V constant (High impedance)...and you're accusing me of putting words in your mouth??....and there's no "straw man" arguments over here. You said the 16ohm to 16ohm option is a "total non issue"... you're incorrect. If you don't want to take my word for it, that's fine. mhammer, myself, and others have outlined our reasoning for why it's important to consider line resistance.
FYI If i read something that doesn't appear accurate, I'm going to comment...whether you like it or not.


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## Frenchy99 (Oct 15, 2016)

OK, let me get this straight...

You guys said to measure the wires... OK, so I did...










Yep, 50 feet ! Now what ???


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## jb welder (Sep 14, 2010)

Granny Gremlin said:


> Doesn't hurt to check tho, and if it is more than 1-2.5 Ohms, you can use the 4 Ohm amp out into an 8 ohm cab since 4 + 3 to 5= 7 to 9 and close enuf.


I'm not clear on what you mean here, so I'll ask for clarification. Cable resistance is outside the OT so it is in series with the speaker and becomes part of the load. It will dissipate a proportion of the power as heat.
So if you have a 3ohm cable, and you use the 4ohm out to an 8 ohm cab, you are matching the 4ohm head to an 11ohm load.
I think if you were trying to compensate by mis-matching, you would set the head to a higher setting than the spkr. cab.

In any case, you lose a bit of power to a resistive cable. Running the highest setting the tube head allows means the cable gets the smallest proportion of that total resistance (sprk R + cable R).


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## Granny Gremlin (Jun 3, 2016)

jb welder said:


> I'm not clear on what you mean here, so I'll ask for clarification. Cable resistance is outside the OT so it is in series with the speaker and becomes part of the load. It will dissipate a proportion of the power as heat.
> So if you have a 3ohm cable, and you use the 4ohm out to an 8 ohm cab, you are matching the 4ohm head to an 11ohm load.
> I think if you were trying to compensate by mis-matching, you would set the head to a higher setting than the spkr. cab.
> 
> In any case, you lose a bit of power to a resistive cable. Running the highest setting the tube head allows means the cable gets the smallest proportion of that total resistance (sprk R + cable R).


 Yeah sorry typed that backwards 8 ohm tap to resistive cable + 4 ohm speaker. 

The point was that nothing ever actually matches perfectly (even an '8ohm' tap to an '8 ohm' speaker) so close enuf is all you ever get anyway. The original power resistor in the first version Herzog was 10 ohm off an 8 ohm tap and the OTs didn't die because of it. Freaking out about a 25-50% mismatch is chicken littleing the thing.


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## nonreverb (Sep 19, 2006)

Granny Gremlin said:


> Yeah sorry typed that backwards 8 ohm tap to resistive cable + 4 ohm speaker.
> 
> The point was that nothing ever actually matches perfectly (even an '8ohm' tap to an '8 ohm' speaker) so close enuf is all you ever get anyway. The original power resistor in the first version Herzog was 10 ohm off an 8 ohm tap and the OTs didn't die because of it. Freaking out about a 25-50% mismatch is chicken littleing the thing.


No one's freaking out here. We're just attempting to help the OP with the best scenario to get the most out of the set up he's about to embark on.....that's all.


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## Frenchy99 (Oct 15, 2016)

So... if I plug my wire in the amp and the other end in the cab I should have sound ???


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## jb welder (Sep 14, 2010)

Frenchy99 said:


> So... if I plug my wire in the amp and the other end in the cab I should have sound ???


What colour is the wire?


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## player99 (Sep 5, 2019)

Here's the wire I bought


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## Frenchy99 (Oct 15, 2016)

jb welder said:


> What colour is the wire?


I ran out of reg wire so am using the red 12 gauge cooper electrical wires instead... had a spindle laying around. Should work no ?


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## nonreverb (Sep 19, 2006)

player99 said:


> Here's the wire I bought
> 
> View attachment 340501


I did the calculation for 12AWG @ 50'. It comes out to .08 ohm (x2) for 0.16 ohms total. I think you're pretty much safe with that. There's no chance of it suffering any heat related issues either.


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## nonreverb (Sep 19, 2006)

Frenchy99 said:


> I ran out of reg wire so am using the red 12 gauge cooper electrical wires instead... had a spindle laying around. Should work no ?


I got a deal on a closet's worth of metal coat hangers...blows the 12 gauge away....sounds better too.


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