When wire DOES make a difference

[DWPress]

For over 30 years I have been running 50 feet of speaker wire because my amps, computer and DAC were all at my desk and speakers at the other end of a 30' room. Things got even worse when I switched to an active XO for my 3-way speakers 15 years ago and I had 7 pieces of 50' speaker wire for the 6 drivers + a sub on that end of the room. Even though I was running 12 gauge wire to the speakers I knew this was less than ideal. A couple years ago I scored a 50' 8ch XLR snake at a good price but had been putting off the chore of relocating the amps, ripping out cable and routing the beefy snake.

Well, over the weekend as a birthday present to myself I decided to dive into the project along with a phono cart upgrade. This is purely subjective because I have no way to ABX this obviously but WOW, quite a difference and I'm able to achieve a higher SPL than previously as well. Even though I used heavy speaker cable and it was routed in parallel it ran next to other AC cables and, until recently, some florescent fixtures. As of now, none of my speaker wires are longer than 9' - that 40' of added impedance wasn't helping anything that's for sure.

A shielded line level signal is nice and clean by any comparison. Not the fastest or easiest tweak I've ever done but a solid one for sure. Now to give the amps a little more airflow and some cable wrap is already in route to my door. Yup, big speakers, not pretty.



edit: To close out the thread hopefully - the change in SPL is attributed to swapping amps on the tweeter channel. Previously was using a Topping PA3 with 19dB of gain on balanced connection and now using a Hypex with 25dB of gain. I misread the 4pt type on the Topping spec sheet and saw the 25dB gain for single ended. Since I'm doing an active crossover things like individual speaker gain and amp gain are controlled in software. However, the whole point of the thread was that line level runs are better than speaker level runs in pretty much any situation.

 

[Cbdb2]

A shielded line level signal is nice and clean by any comparison. Not the fastest or easiest tweak I've ever done but a solid one for sure. Now to give the amps a little more airflow and some cable wrap is already in route to my door. Yup, big speakers, not pretty.

If its unbalanced, 50' of line level cable might have enough capacitance to roll of the high end. Depends on the cable and the input impedance of the input.

 

[LTig]

For over 30 years I have been running 50 feet of speaker wire because my amps, computer and DAC were all at my desk and speakers at the other end of a 30' room. Things got even worse when I switched to an active XO for my 3-way speakers 15 years ago and I had 7 pieces of 50' speaker wire for the 6 drivers + a sub on that end of the room. Even though I was running 12 gauge wire to the speakers I knew this was less than ideal. A couple years ago I scored a 50' 8ch XLR snake at a good price but had been putting off the chore of relocating the amps, ripping out cable and routing the beefy snake.

Well, over the weekend as a birthday present to myself I decided to dive into the project along with a phono cart upgrade. This is purely subjective because I have no way to ABX this obviously but WOW, quite a difference and I'm able to achieve a higher SPL than previously as well. Even though I used heavy speaker cable and it was routed in parallel it ran next to other AC cables and, until recently, some florescent fixtures. As of now, none of my speaker wires are longer than 9' - that 40' of added impedance wasn't helping anything that's for sure.

Hmm. According to wikipedia a 12 gauge wire has 0.0015 Ohm/ft.

• 50 ft of wire result in a resistance 50 x 0.0015 x 2 (two conductors) = 0.15 Ohm.
• 9 ft of wire result in a resistance 50 x 0.0015 x 2 (two conductors) = 0.027 Ohm.
• With a 4 ohm speaker we would see an SPL of 20 x log10(4/(4+0.027)) = -0.05 dB for the 9 ft cable, and 20 x log10(4/(4+0.15)) = -0.32 dB for the 50 ft cable, which results in a SPL difference of 0.27 dB. This is audible but far from WOW.

 

[MusicNBeer]

... which results in a SPL difference of 0.27 dB. This is audible but far from WOW.

Maybe the 30 year old speaker cable was oxidizing, raising it's resistance. Still, for me the WOW would be the frequency response no longer affected by the series resistance, rather than raw SPL difference.

 

[LTig]

Maybe the 30 year old speaker cable was oxidizing, raising it's resistance. Still, for me the WOW would be the frequency response no longer affected by the series resistance, rather than raw SPL difference.

This would flatten FR, reducing the typical loudness effect desired by tube lovers, which is their Wow factor.

 

[DWPress]

I have no other way to explain where the additional dB difference is coming from. Absolutely nothing else has changed. The speaker wire was fine, no oxidation. At the very least I think we can all agree - long cable runs are better at line level and shielded.

BTW, I don't need the SPL, just an unexpected benefit. I was getting a clean 104dB before which is more than enough lol, check gear list below...

 

[kemmler3D]

A 50-foot run past unfriendly electronics like fluorescent lights is probably one of the better use cases for balanced cables. If nothing else you probably got a drop in noise floor. That said, balanced signals are usually 2x amplitude (right?) so we have to consider changes in level as likely causes of "wow factor" here.

 

[DWPress]

Perhaps my term "WOW" is taken slightly out of context here though I appreciate you all focusing on that, it is ASR after all.

These are the changes I made:

50+ feet of 12 gauge speaker wire (x7) reduced to < 9'
6 feet of balanced cables replaced with 50' XLR (x8) snake
I swapped the Topping PA5 v1 I was using with the tweeters to the extra 2 channels on my 4ch Buckeye NC252mp but both amps have the same output gain and are only used for 3700-20kHz so pretty overkill either way and not a lot of music power in that range anyway.

And yet for some reason I can no longer comfortably turn the volume of my Okto dac8 Pro up beyond -10dB. Somehow I gained SPL and quite a bit. As I said before, this was not my goal. I live rural, noise floor in the studio is about 35dB and prior to the changes the system could easily do 105dB of solid undistorted music of any kind with still plenty of power left for dynamic headroom, now I hit 108dB (at 12' away) with the same meter. I've been building speakers for 30 and doing it with active crossovers and DSP for over 15 years and I like to tweak things so I am perhaps overly familiar with my digital signal processing chain and nothing changed there during this "upgrade".

My, perhaps slightly click baity, thread title was only meant to imply that one sort of cable is better than another for moving audio information even if line level and speaker level are different things. There is nothing I can buy (perhaps new $$,$$$ speakers) to make any improvements to the sound in this room so I was proud of myself for taking on this chore that I didn't expect to make any difference at all.

 

[coonmanx]

So... Are you actually measuring dBs with a meter?

 

[DWPress]

Yes. Just a phone app but I find it comparable to my Umik and REW. It's actually annoying to have gained dBs, guess I can give my DSP some more headroom to get rid of some of it.

 

[Speedskater]

If its unbalanced, 50' of line level cable might have enough capacitance to roll of the high end. Depends on the cable and the input impedance of the input.

If it is a modern interconnect system, with low output impedance and high input impedance, then No the high end will not roll off.
The roll-off idea is an old using the wrong formula mistake.

 

[DWPress]

It was 50' (x7) of speaker wire not unbalanced cables and I've never had an issue with high frequency roll off.

 

[egellings]

When wire lengths get that long, they can influence SQ. For normal short living room lengths, the effect will not be noticeable for reasonably selected types.

 

[DWPress]

I haven't done any sort of measurements since the change because I'm swapping tweeters within the week so new crossovers and plenty of measurements are coming. I scored some nice Audax TW034X0 34mm domes that reach a bit lower than the Fountek ribbons I've been using and should match up with the midrange better before beaming begins in in those drivers (Dayton RS150P-4). I'll run sweeps and MMM before the work though so I'll have recent measurements to compare against.

 

[Timcognito]

They have LEDs that fit in almost every florescent scocket and no ballast needed, no buzzing. I replaced 20 4ft bulbs in my workshop/garage and love all the light. Recycled the ballasts and cut 320 watts off the florescent in the existing fixtures.

 

[DWPress]

They have LEDs that fit in almost every florescent scocket and no ballast needed, no buzzing.

I did this a couple years ago, you can see the tubes in the first post pics. Much better quality of light too.

 

[pseudoid]

The audio world does not work in the old binary formula of "Mohamed and the Mountain".
100feet of cabling (+/- round trip per channel) just seems to be an abnormal length for speaker runs. (imo)

When I was confronted with such dilemma, a few years back, I resorted to 75feet of outdoor grade, 22AWG, copper. SFTP (8P8C) configured, Cat6a cable.
I use that cable for networking upstairs/downstairs; while also routing PoE surveillance video, and PoE Dante audio thru it... without getting approval from either Mohamed nor the Mountain.

 

[Speedskater]

We seem to be co-mingling different types of cables in this thread.

 

[pseudoid]

Does long runs of speakers cables getting replaced by alternative solutions considered co-mingling?
If anything I am inclined to think that a replacement can help prevent cable co-mingling (=noise/emi coupling).

 

[egellings]

Does long runs of speakers cables getting replaced by alternative solutions considered co-mingling?
If anything I am inclined to think that a replacement can help prevent cable co-mingling (=noise/emi coupling).

Maybe co-mingling was intended to imply both speaker and small signal cables.