Do the type/brand of XLR Cables really matter? - Page 3 - AVS Forum | Home Theater Discussions And Reviews
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post #61 of 89 Old 09-08-2018, 07:57 PM
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Originally Posted by Ethos4Lyfe View Post
Immediately, the db level was higher.. . .
Also, it 100% seemed like the bass response was better - it was just more prevalent...I just hearing more bass than I was previously.
That's called the Fletcher-Munson equal loudness curve effect.

In A/V reproduction accuracy, there IS no concept of "accounting for personal taste/preference". As art consumers we don't "pick" the level of bass, nor the tint/brightness of a scene's sky, any more than we pick the ending of a novel or Mona Lisa's type of smile. "High fidelity" means "high truthfulness", faithful to the original artist's intent: an unmodified, neutral, accurate copy of the original master, ideally being exact and with no discernable alterations, aka "transparency".
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post #62 of 89 Old 09-08-2018, 08:28 PM
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Originally Posted by m. zillch View Post
That's called the Fletcher-Munson equal loudness curve effect.
sooo...does that mean its actually louder, or im perceiving it? i mean, it seems to me that i noticed a difference, so seems like it was worth the purchase for me LOL
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post #63 of 89 Old 09-08-2018, 09:42 PM
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Quote:
Originally Posted by Ethos4Lyfe View Post
sooo...does that mean its actually louder, or im perceiving it? i mean, it seems to me that i noticed a difference, so seems like it was worth the purchase for me LOL
It should be 6db louder with XLR as it has twice the output voltage. I know on my 7702 going from RCA to XLR it increases 3db and running Audyessy will reflect this as it set the speaker and subwoofer levels lower accordingly.

You are not actually gaining 3db of more output but you get the other benefits of XLR vs RCA along with the increased output voltage going from RCA to XLR. I notice less system noise overall going from RCA to XLR. Using a normal tweeter it probably is as noticeable but using a high-efficiency horn loaded driver any noise is easily heard when there is no music playing, so a lower noise floor.

I would stay away from cheap Monoprice XLRs and RCAs as they have poor fitting connections. I had good luck with Mogami XLR and they are reasonably priced and much better connections that are snug. https://www.markertek.com/product/ms...e-3-foot-black

From your 8805 manual...........Rated output:

Unbalanced RCA pre-output: 1.2 V

Balanced XLR pre-output: 2.4 V

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post #64 of 89 Old 09-08-2018, 10:00 PM
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Originally Posted by Ethos4Lyfe View Post
Well, I can honestly tell a difference. I have never bought into the more expensive cabling theory...but, I get great deals cables (35-40% off) and I get to try them for a bit before I make a decision. I unhooked the flimsy amazon cables and connected some AQ Mackenzies. Immediately, the db level was higher. I was watching the same youtube content I watched earlier in the day, and I had to turn it down...so, it was playing the same volume but at lower settings. Not sure what that does for me overall, but interesting to note.

Also, it 100% seemed like the bass response was better - it was just more prevalent...I just hearing more bass than I was previously. I only did the front 3 speakers, and plan on keeping it - for less than $225 I don't have a problem keeping them. I don't think its placebo effect (LOL) because I actually did need to turn the processor master volume done while watching the same content. Again, not sure what that means for me in real world usage/value, but I'm okay with it.
Just to be clear: you replaced cheap Amazon XLR cables with AQ ones and heard a significant increase in volume, all other things being equal?

That's, er, unexpected.
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post #65 of 89 Old 09-08-2018, 10:12 PM
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Originally Posted by bobknavs View Post
Just to be clear: you replaced cheap Amazon XLR cables with AQ ones and heard a significant increase in volume, all other things being equal?

That's, er, unexpected.
yes - i had to lower the video i was watching on youtube. it was just louder once i hooked up AQ. that could just be because less signal interference maybe? better cables/sheathing, allowing less noise?
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post #66 of 89 Old 09-08-2018, 10:20 PM
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Quote:
Originally Posted by Ethos4Lyfe View Post
yes - i had to lower the video i was watching on youtube. it was just louder once i hooked up AQ. that could just be because less signal interference maybe? better cables/sheathing, allowing less noise?
No, the volume should be unchanged. Noise would be additive.
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post #67 of 89 Old 09-08-2018, 10:28 PM
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Originally Posted by bobknavs View Post
No, the volume should be unchanged. Noise would be additive.
I mean, I'm fairly new to all this. But, basically - I had a Youtube video on -22 on my Marantz. I turned everything off, and swapped the front 3 cables. I turned the same video back on, sstood at same distance and it was just louder. I set the master volume to -25 or -27 and it sounded around the same it had previously. So, who knows. There could be other things - maybe my a/c had turned off or noise outside had stopped? LOL I have no idea. Either way, I don't have a problem spending around $200 on cables for gear that I spent this much on....now, going up further to their water cable that are like $400 each seems excessive.
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post #68 of 89 Old 09-09-2018, 02:28 AM
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Quote:
Originally Posted by Ethos4Lyfe View Post
yes - i had to lower the video i was watching on youtube. it was just louder once i hooked up AQ.
How many dB difference, out of curiosity? [Meaning, please look at your volume display number and see how many dB you need to crank up the cheap Amazon wire in order to match the level you hear from the AQ] Thanks.

Try using pink noise instead of music:

It is steadier and more consistent.
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post #69 of 89 Old 09-09-2018, 11:10 AM
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Sounds like the Amazon cables may have been either defective or wired wrongly for your system (there are two "standards" in relatively widespread use around the world for wiring the connectors). That would create a single-ended connection and explain the level difference.

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #70 of 89 Old 09-09-2018, 01:12 PM
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Originally Posted by DonH50 View Post
Sounds like the Amazon cables may have been either defective or wired wrongly for your system (there are two "standards" in relatively widespread use around the world for wiring the connectors). That would create a single-ended connection and explain the level difference.
Although the pin-out configuration of jacks on the gear sometimes use one of two standards*, the male-to-female balanced XLR audio cables we buy don't, i.e. XLR Pin 1, 2, and 3 adhere to a standard, EIA RS-297A (with the exception of a cable sold specifically as a "reverse polarity cable"). There may be exotic designs which have an optional "ground lift feature" (more often found on the gear itself, not the cable) however customers buying 3-pin, male-to-female XLR cables, aka XLR3, for balanced runs, be it mic level or line levels, professional or consumer, need not worry that there are two types of pin configuration they might buy.

If I was wrong about this and there were indeed two types then when we shop for XLR cables we'd see a designation like "6 ft, male to female, EIA RS-297A pin-out configuration" vs. say "6 ft, male to female, 1950's Japan pin-out configuration". In modern times they are all the same standard.

https://upload.wikimedia.org/wikiped...inouts.svg.png
Pin Function
1 Chassis ground (cable shield)
2 Positive polarity terminal for balanced audio circuits (aka "hot")
3 Negative polarity terminal for balanced circuits (aka "cold")

*In a situation where a consumer plugs from one device to another using the alternate standard in the second device's jack then Pins 2 and 3, hot and cold, become flipped hence the polarity of the signal is reversed but there is no other apparent change. The level stays the same. This is where a polarity flipper such as the one I linked to above might come in handy or alternatively the red and black speaker wire connections on that channel's amp could be flipped to solve the issue.

Of course many/most XLRs can be opened up and re-soldered so the pin out can be whatever a consumer wants, including using some differing grounding methodologies in situations when going from a balanced output to an unbalanced input, however if the ad just says "M-to-F XLR balanced audio cable" you are good to go.

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post #71 of 89 Old 09-09-2018, 01:48 PM
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Quote:
Originally Posted by m. zillch View Post
How many dB difference, out of curiosity? [Meaning, please look at your volume display number and see how many dB you need to crank up the cheap Amazon wire in order to match the level you hear from the AQ] Thanks.

Try using pink noise instead of music:
https://www.youtube.com/watch?v=8SHf6wmX5MU

It is steadier and more consistent.
for that video, i lowered it about 3-4 levels. so from -22 to about -25 or -26 and it sounded the same level then.
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post #72 of 89 Old 09-09-2018, 01:53 PM
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There are still components today using the European standard, e.g. the current crop of Emotiva gear and some pro mixers and such. I don't agree with that choice but they are doing it. Another variant is how to ground the connector case -- tie to pin 1 and connecting to the cable shield, leave floating, or tie via a small-value (RF) capacitor to provide an RF ground but not audio ground. Several of the major companies sell several variants, or did last I checked (last year when I bought new cables for a processor), but they are typically special order. I opted for the standard (EIA/AES) configuration even for my Emotiva processor figuring (a) the processor would handle the inversion for me and (b) I did not want more non-standard cables in my gig bag (already have a few, specially marked and labelled so I -- hopefully -- don't grab the wrong one).

The problem with signal loss is when the miswired cable/connector leads to grounding one side of the balanced signal. Usually an issue with the component and not the cable. Polarity inversion will not cause signal loss unless it happens on one channel and not the other (resulting in e.g. L and R channels in different relative polarity). A number of companies have had bad batches of cables that inadvertently shorted one side to ground when plugged into a "normal" connector. I have had bad ones from some pretty high-profile companies now and then through the years, and they usually send out a recall notice. It is rare IME. I have no idea if that is the case here, just seems curious there is such a difference in signal level, thus the comment.

Another potential problem is that a wire is not connected due to a bad connector or broken wire. That would also cause signal loss. Unless a whole batch is bad, swapping cables would fix that.

Finally, some components include a balanced/unbalanced switch, and leaving it in the wrong position can short one side of a balanced input to ground. This depends upon how the manufacturer implemented the input connections and the switch, of course. Ideally that would never happen, but one of my old amps did exactly that, much to my dismay. I had RCA and XLR cables plumbed and setting the switch to "Unbalanced" shorted one side the the XLR to ground. Seemed odd to me, and led to an interesting round of troubleshooting, but strange things happen.

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post #73 of 89 Old 09-09-2018, 03:17 PM
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Quote:
Originally Posted by DonH50 View Post
... = -0.000087 dB. I don't think you need to worry about the small wire gauge. Actually, since it is two wires into a balanced input, it should be 20*log10(200000/200004) = -0.00017 dB loss for 100' of cable. ...- Don
Are you sure?

Oh, wait. That is way less than the 0.1 dB that we level match in a DBT.
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post #74 of 89 Old 09-09-2018, 03:19 PM
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If we are certain there is a 3dB shift based on brand of XLR cable used, then that implies there is a mis-wiring or faulty connection in one of the wires.

Do they open up easily to inspect how they are wired and if any solder points have cracked or are "cold joints"?
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post #75 of 89 Old 09-10-2018, 02:42 PM
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I was wondering the same after I received the FosPower

Left is XLT to RCA


Middle is RCA RCA, Right RCA to RCA


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post #76 of 89 Old 09-10-2018, 02:59 PM
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Just tuned in....

FYI: If an XLR has one signal (not ground) wire missing, you get 1/2 the voltage = 6 dB loss. Strange things happen if you wire the cable shield to pin 2 or 3, I had a guy make that mistake once.

I worked as a pro recording and live sound engineer and know a lot of people in the industry. One I respect told me he used Mogami W2549 for balanced interconnects. Switchcraft or Neutrik connectors are both well made.

https://www.redco.com/Mogami-W2549.html

I use Mogami W2497 for unbalanced interconnects. https://www.redco.com/Mogami-W2497.html

I have also used Gepco, Canare, Belden and Gotham Audio cable. All are good.

I get cables made from Redco or Blue Jeans Cable. It's not worth it to me to break out the soldering iron to make a few cables. If I need a lot, I may do it, but don't really enjoy it much after three decades and making hundreds of cables of all types (balanced, unbalanced, RCA, 1/4", XLR etc).

Last edited by Rex Anderson; 09-10-2018 at 04:26 PM.
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post #77 of 89 Old 09-10-2018, 03:59 PM
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Quote:
Originally Posted by Rex Anderson View Post
Just tuned in....

FYI: If an XLR has one signal (not ground) wire missing, you get 1/2 the voltage = 6 dB loss. Strange things happen if you wire the cable shield to pin 2 or 3, I had a guy make that mistake once.

I worked as a pro recording and live sound engineer and know a lot of people in the industry. One I respect told me he used Mogami W2549 for balanced interconnects. Switchcraft or Neutrik connectors are both well made.

https://www.redco.com/Mogami-W2549.html

I use Mogami W2497 for unbalanced interconnects. https://www.redco.com/Mogami-W2497.html

I have also used Gepco, Canare, Belden and Gotham Audio cable. All are good.

I get cables made from Redco or Blue Jeans Cable. It's not worth it to me to break out the soldering iron to make a few cables. If I need a lot, I may do it, but don't really enjoy it much after three decades and making hundreds of cables of all types (balanced, unbalanced, RCA, 1/4" XLR etc).
This is something I've always wondered. Do the audiophiles who buy into the whole uber-expensive boutique cable thing think the studios who recorded the artist they're listening to used the same boutique cables to make the album? Or did the studio use quality, but bought in bulk cables like you listed or similar cables from a studio gear supplier.

I'm betting 99% of studios aren't spending $1,000 for a meter of fancy named XLR cable. So that means there's folks spending hundreds to thousands of dollars on cables for the home HiFi just to listen to artists who recorded in a studio using monoprice-like stuff.
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post #78 of 89 Old 09-10-2018, 04:24 PM
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Originally Posted by 2WheelsWillTravel View Post
This is something I've always wondered. Do the audiophiles who buy into the whole uber-expensive boutique cable thing think the studios who recorded the artist they're listening to used the same boutique cables to make the album? Or did the studio use quality, but bought in bulk cables like you listed or similar cables from a studio gear supplier.

I'm betting 99% of studios aren't spending $1,000 for a meter of fancy named XLR cable. So that means there's folks spending hundreds to thousands of dollars on cables for the home HiFi just to listen to artists who recorded in a studio using monoprice-like stuff.
The majority of studio engineers I known (including some Grammy winners) use cables from the companies I mentioned. Some have experimented with "boutique cable" and may use them in critical applications. At one time Bob Ludwig (famous mastering engineer) said his speakers were wired with MIT cable, very expensive stuff.

I don't think many audiophile folks think about the recording process and what goes on in the studio. It is interesting to think, a signal chain might be a $10,000 vintage tube microphone into a channel on a $500,000 mixing console using a $20 mic cable. Happens all the time....
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post #79 of 89 Old 09-10-2018, 04:57 PM
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Audio cables are the easist thing in the world for a consumer to test on their own under blind or even double blind conditions with the help of a friend or two yet I've rarely ever seen anyone attempt it.

Simply take any line level source like a CD player, DAC, phono preamp, etc. and split the L and R outputs with two y-cords. Connect the two competing RCA wires to these splits and feed the other ends to two different line level inputs on your preamp or receiver such as CD, Aux, Tape, Video, etc.. Now you can toggle between these two inputs on your preamp/receiver to your hearts content. Hear a difference? No? Then the wire makes no difference.

Have a friend do it while you aren't looking and you have a blind test. . . . Have a friend wire the two inputs while you aren't in the room and select what wire goes to what input randomly by coin toss [Hmm, should the expensive one go to CD and cheapo to Aux? Or the other way around?] and you have a double blind test. [The friend also must leave the room before you enter and no other communication between you is allowed, nor peeking behind the gear to see what's connected where, of course.] Do 10 trials or so, randomizing what wire goes to what input each time with (literally) a coin toss each trial.

I challenge my friends who claim to hear differences to bets just like this and I always win. It's a fun way to make money.

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post #80 of 89 Old 09-10-2018, 05:42 PM
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Quote:
Originally Posted by bscool View Post
It should be 3db louder with XLR as it has twice the output voltage. I know on my 7702 going from RCA to XLR it increases 3db and running Audyessy will reflect this as it set the speaker and subwoofer levels lower accordingly.

You are not actually gaining 3db of more output but you get the other benefits of XLR vs RCA along with the increased output voltage going from RCA to XLR. I notice less system noise overall going from RCA to XLR. Using a normal tweeter it probably is as noticeable but using a high-efficiency horn loaded driver any noise is easily heard when there is no music playing, so a lower noise floor.

I would stay away from cheap Monoprice XLRs and RCAs as they have poor fitting connections. I had good luck with Mogami XLR and they are reasonably priced and much better connections that are snug. https://www.markertek.com/product/ms...e-3-foot-black

From your 8805 manual...........Rated output:

Unbalanced RCA pre-output: 1.2 V

Balanced XLR pre-output: 2.4 V

2 x voltage is an increase of 6 dB.

dB change = 20log(2)

log(2) = .3
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post #81 of 89 Old 09-10-2018, 08:00 PM
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Quote:
Originally Posted by bigguyca View Post
2 x voltage is an increase of 6 dB.

dB change = 20log(2)

log(2) = .3
Thank you for the correction. I'll edit my post so it has the correct info.

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post #82 of 89 Old 09-18-2018, 01:17 PM
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Quote:
Originally Posted by DonH50 View Post
Krell Chorus 5200 balanced input impedance = 200 k-ohms
24 AWG wire = 0.020 ohms/foot

So if you had 100' interconnects to the amp that is 100 * 0.02 = 2 ohms driving into 200 k-ohms. You'll lose 20*log10(200000/200002) = -0.000087 dB. I don't think you need to worry about the small wire gauge. Actually, since it is two wires into a balanced input, it should be 20*log10(200000/200004) = -0.00017 dB loss for 100' of cable. Still think you'll be OK. Spend the money on movies or music. Or I can PM you my address and you can send it to me.

Oh, capacitance, say 25 pF/ft so now if only considering the 100' cable you'll be about -3 dB at about 1/(2*pi*4 ohms*2500 pF) = 15.9 MHz. Nope, still probably OK, even with the ears of a bat.

FWIWFM - Don

In the audio world the cable will be driven by say a preamp that will have a non-zero output impedance. This preamp output impedance has be included in the calculations of the -3dB point.

Here are a few examples using the cable characteristics above. The -3 dB point is above the 20 kHz limit of hearing in all cases, but comes close with lower level equipment:

Let's say a PRO preamp has an output impedance of 50 ohms - that makes the calculation 1/(2*pi*54*ohms*2500 pF) = 1,179 kHz


Similarly for:

36 ohms - Mark Levinson Preamp No. 326s = 1,595 kHz

60 ohms - Benchmark HPA4 Line Amplifier or DAC3 - 1,061 kHz

100 ohms - For reference - 612.1 kHz

Approx. 400 ohms - Marantz AV7704, Marantz AV8805, Yamaha CX-A5100 - 157.6 kHz


In many AVR's the SE output is driven directly by the volume control, so the output impedance of the volume control is included. In the devices above with lower output impedances, the output is driven by a buffer such as the HDAM's in the Marantz equipment, or opamps in other brands. SE cables may have different characteristics, but let's use the ones above for the rest of this. There are enough numbers, calculations and chances for errors already!

Approx. 520 ohms - SE - Denon X8500H - 122.4 kHz

1,000 ohms - for reference, the SE outs on many AVR's are at this level or above - 63.4 kHz

Approx. 1,400 ohms - SE - Example mid-level AVR - 45.5 kHz
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post #83 of 89 Old 09-18-2018, 01:38 PM
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I started to include the output impedance but when a quick search turned up anywhere from ~1 ohm to ~1 k-ohm outputs I gave up and figured it would just muddy the waters and I was too lazy to run all the numbers. Thanks for doing that!

Typical SE cables are in the 20 ~ 30 pF/ft range and the few XLR cables I found were the same or a little higher so I just used 25 pF/ft and called it a day.

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post #84 of 89 Old 09-18-2018, 02:31 PM
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Quote:
Originally Posted by bigguyca View Post
Approx. 1,400 ohms - SE - Example mid-level AVR - 45.5 kHz
for a 100ft cable with 25pF/ft

i have two sets of XLR cables, 3ft for side by side and 1.5ft for stacked and even with the 3ft cable and the poor 1400Ohm output we end up with 1.5MHz
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post #85 of 89 Old 09-18-2018, 03:23 PM
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Approx. 1,400 ohms - SE - Example mid-level AVR - 45.5 kHz
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Originally Posted by Mickey Mouse View Post
for a 100ft cable with 25pF/ft

i have two sets of XLR cables, 3ft for side by side and 1.5ft for stacked and even with the 3ft cable and the poor 1400Ohm output we end up with 1.5MHz

Based on the example, don't forget to purchase some SE to XLR adapters. One adapter needs to be XLR female to SE and the other XLR male to SE assuming your XLR cables are female on one end and male on the other.
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post #86 of 89 Old 09-19-2018, 01:34 PM
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In the audio world the cable will be driven by say a preamp that will have a non-zero output impedance.
Sure the pre Zout needs to be taken into account when comparing BW, but few if any real use (home) cables are going to be 2500pF and especially with SS gear Zin on a power amp is likely to be 10k SE, 20k balanced so out there examples aren't much help for a non technical punter who doesn't really understand the numbers.


Of all the service manuals of AVRs I have, I cannot recall seeing a single unit that drove the pre outs off a pot wiper. By and large they go from a buffered DAC out to the pre outs, paralleled to the internal amps. All processing and VC is done in the DSP.

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typical values are about 30pF/ft for the cables and you have to dig in deep **** to find a pre with more than 1kOhm output impedance.

Last edited by DrDon; 09-19-2018 at 05:38 PM. Reason: condescending remarks removed
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post #88 of 89 Old 09-24-2018, 04:42 PM
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Sure the pre Zout needs to be taken into account when comparing BW, but few if any real use (home) cables are going to be 2500pF and especially with SS gear 1) Zin on a power amp is likely to be 10k SE, 2) 20k balanced so out there examples aren't much help for a non technical punter who doesn't really understand the numbers.


Of all the service manuals of AVRs I have, 3) I cannot recall seeing a single unit that drove the pre outs off a pot wiper. By and large they 4)go from a buffered DAC out to the pre outs, paralleled to the internal amps. All processing and VC is done in the DSP.

1) The SE input would typically be 20k ohms or greater. The resistor that sets the input impedance isn't in the an SE input isn't in the signal path and doesn't contribute Johnson noise, so the resistor can be large. 10k ohms would be needlessly low.

2) A typical single opamp differential amplifier input (per your 20k example) with 4 x 10k ohm input resistors has an input impedance of 20k ohms on the hot, 20k ohms common mode, but 6.67 ohms on the cold (-) input.

3) Agreed, but relevance?

4) This will never be the case in an AVR. The outputs of the DAC will go to an opamp that sets gain, provides filtering and buffers the output (modestly), The output of this opamp goes to a volume control, normally an 8-channel unit from NJR or ROLM. This volume control is a key component in the AVR. In your example it isn't clear how the AVR would control volume. The volume control is a CMOS chip that provides gain (+ or -) via switched resistors that change the gain of a an opamp circuit in the chip. The ROLM unit also has opamp output buffers. Typically single-ended inputs to an AVR go directly to the volume control, or to CMOS switches in the case of the NJR unit, and then to the volume control.

At least for higher level units; from the volume control the signal typically goes to the preamp outputs or power amplifier inputs in the case of Denon, to the HDAM's and then to the preamp outputs or power amplifier inputs in the case of Marantz, and to the power amplifiers or opamp buffers or directly to the preamp outputs in the case of Yamaha. Balanced outputs are obtained by inverting the SE output using an opamp or HDAM circuit depending on the specific unit. Some units have switches to control which signal goes to which amplifier.
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1) The SE input would typically be 20k ohms or greater. The resistor that sets the input impedance isn't in the an SE input isn't in the signal path and doesn't contribute Johnson noise, so the resistor can be large. 10k ohms would be needlessly low.
Comment is based upon having thousands of different audio amps across my bench for repair over the decades, both home and commercial. 10k is not an unreasonable value and very easy for a modern opamp to drive. However, my point that you seemed to have missed is that it will usually be low enough that any reasonable amount of capacitance in an interconnect is not going to make a FR difference in the audible bandwidth. Of course poor implementations and stupidly capacitive cables do exist.

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