Speaker cable thickness for 2 Ohm subwoofer

[Geertidow]

Dear fellow forum members,

I have a 2 Ohm subwoofer on a hypex NC500MP. Has been working fine for over 4 years now.

But, just swapped to a smaller speaker cable. 1.5 mm2 thickness copper.
Total length is 4 meters.

Is this OK or should I use thicker cable?

Thanks for your help.

 

[AdamG]

Speaker Wire

 

[Geertidow]

Then I may have a slightly too small cable. I'll fix it thanks

 

[OldHvyMec]

2 or < ohms can get HOT. Subpar wire size and add a loose connection; you can get into real trouble. I've seen a few vehicles burn to the ground behind
both issues. Double the run or buy a larger conductor. Make sure the connection are tight. It just doesn't cost that much to be safe.

Regards

 

[Geertidow]

The connections are safe with big QED connections. But I'll swap it with a larger cable.

 

[Lambda]

Bigger is better... I would go with 2,5mm² maybe even 4mm²
But i don’t think i would hear a difference to 1,5mm²

 

[Ropeburn]

Wire is cheap, so there's really no reason to skimp on it - except bigger diameters tend to grow too big for the usual plugs (banana etc.) and terminals at a point. That's how you know it's more than big enough. Example:

Made these from 4mm² automotive wire, 20m for 30€. 2x 2.5m result, total 8mm² - complete overkill, but what the hell. Why not? It costs next to nothing. Only reason for bi-wire configuration at the speaker end is the plugs I had flying around were too small for 8mm².

Use what you have or can get for cheap, and while you're at it, as big as possible for the lols - nice side effect is plenty of safety margin built in. Fun fact: that automotive wire is electrolytic copper 99.9%, some common industry standard. Not even audiophools could complain about it.

 

[Steven Holt]

Here, they'll fix ya up www.bluejeanscable.com

 

[Geertidow]

I don't like big cables and I've never heard a difference. I just used two cables of 1.50 mm2 (separate plus and minus cable). That should be sufficient.

 

[Speedskater]

Well let see, 500 Watts into 2 Ohms is about 15 Amps. So a 14AWG (2.0mm) wire could care a full volume test tones all day.
Also music with 1000 Watt peaks.

 

[AnalogSteph]

Well let see, 500 Watts into 2 Ohms is about 15 Amps. So a 14AWG (2.0mm) wire could care a full volume test tones all day.

Usually current carrying capacity isn't so much the limiting factor, resistance / damping factor is, especially since it's added to the amplifier's output impedance. If your amp only has a DF of 60 @ 8 ohm to begin with (i.e. 15 @ 2 ohms), it doesn't take that much to push DF below 10. Now a naked sub sans crossover arguably doesn't need a super high DF to begin with, but still. Thankfully the NC500MP can manage a DF of 1000 @ 2 ohms below 1 kHz (meaning it's negligible vs. any but the fattest / shortest cables), so there is a good bit more leeway in this case. The whole shebang should still manage a DF of around 20 even with the current 1.5 mm² wiring, so even that is arguably fine.

 

[Speedskater]

Damping factor with modern amplifiers is no longer a concern.

 

[HaveMeterWillTravel]

The other issue of "damping factor" as commonly used is it completely ignores the mechanical components which dominate the behavior of the total system.
Back "then" the ability to accurately measure the real time excursion/movement of a driver were rather limited. Not so now. IIRC, Klippel was the first commercial system to incorporate a laser displacement meter and that was 20+ years ago.

However that itself is semi-academic since the end user has the ability to measure the impulse response of the total system (source/amp/speaker/room) and apply real time corrections.

 

[Sokel]

Purifi has some interesting thoughts here:

PURIFI finally did a fully purified passive speaker design! The SPK 16 prototype is here - with a PTT tweeter

I thought you were joking, looks like you really had problems with vertical shift. Philharmonic BMR Monitor directivity: Horizontal -6dB beam width 160° (+/- 80°) Vertical -6dB beam width 40 ° (+/- 20°) Reference: https://www.erinsaudiocorner.com/loudspeakers/philharmonic_bmr/ Sitting...

www.audiosciencereview.com

(read the three posts under mine)

 

[HaveMeterWillTravel]

The assumption is the speaker system is the same in either case. So, considering driver mechanics is a non-sequitur.
Speaker wire resistance adds with Rs. But both together are insignificant relative to Re. This is the basic point.

Dave Reite.

the assumption that the speaker system is linear and has no effect upon the other components in the system is not based upon any evidence.
It also is importance to consider with respect to significance. Any change in system “damping due to small changes due to the amplifier is most likely insignificant compared to the loudspeaker.
Even the worst amplifier “damping factor” is orders of magnitude better than a woofers.

As an analogy, the significance of the difference of SINAD between -120 and -180 is insignificant against the difference between -40 and -100.
Or -0.1 dB versus -10dB
.

 

[Holmz]

Dear fellow forum members,

I have a 2 Ohm subwoofer on a hypex NC500MP. Has been working fine for over 4 years now.

But, just swapped to a smaller speaker cable. 1.5 mm2 thickness copper.
Total length is 4 meters.

Is this OK or should I use thicker cable?

Thanks for your help.

How does it sound now?

 

[ZolaIII]

If cable stays under or a bit above body temperature when you drive it very loud (for you) it's fine. If it gets hot you need thicker conductor one. Really no reason to skim on it good OFC AWG 10 (4 mm) starts at about 1.5 € for m. Don't use car cables all do they can do very high A they are very stiff (single thick conductor). Buy a normal one from normal brand that provides full spec's (what ever is cheaper from such where you are).

 

[Geertidow]

The same as always. I just don't want to set the house on fire or murder my amp.

 

[HaveMeterWillTravel]

The assumption is the speaker system is the same in either case. So, considering driver mechanics is a non-sequitur.
Speaker wire resistance adds with Rs. But both together are insignificant relative to Re. This is the basic point.

Dave Reite.

My comment was in the wider scope of whether or not damping factor 'matters' from an system modeling/measurement viewpoint.
Understanding is key to fending off snake oil.