I give up... TRS vs TS, Bal vs Unbal, LowZ vs HiZ

[kpsychedelic]

Ok thanks a lot for the insights.

Having read the owner's guide of your A&H ZED-10 (have you??)

Yes I did, sorry if I sounded lazy
But still, it only contains a few pages (well at least the printed version bundled, maybe I did commit the error of not checking some PFD online) and although it explains the inputs well, there are things that are left in the blue, because obviously they just describe the features, but not really need to explain all of these questions I had, they are more of general audio knowledge.

If you connect the 3.5mm to a 1/4" TRS adapter, then on the TRS plug you have the left channel on the tip and right channel on the ring, with the sleeve being common ground. That's stereo on a single plug

Ok got it. Maybe I still needed a bit of the "inside" knowledge of contruction of these cables, because probably there is no such thing as 3.5mm to "dual" 1/4" TRS.

The simplest solution in this case is to use a bog-standard 3.5mm --> RCA cable, plug that into a stereo channel of the mixer, which by chance also has RCA inputs. You could also fit 1/4" TS adapters on the RCA plugs and plug those on a pair of TRS inputs.

When you say a pair of TRS you mean the stereo channel dual "line-ins", right?
Although re-reading the manual they don't say if those line-ins are TRS or TS in the end, but yeah, I get it as RCA should be totally fine or a couple TS jacks inside them.

you have to stop thinking that TS/TRS has anything to do with the signal. All it is, is how many wires there are in the cable (if fully wired).

Ok thanks for the explanation.

[thecontrolcentre]

Maybe buy the cables, connectors and a soldering iron and make your own ... it will probably help your understanding.

[simonden]

Ok got it. Maybe I still needed a bit of the "inside" knowledge of contruction of these cables, because probably there is no such thing as 3.5mm to "dual" 1/4" TRS.

So either use the cable that thecontrolcentre mentioned to go through the stereo channel or use a 3.5mm to dual 1/4" TS and plug into channels 1 and 2 (or 3 and 4) and pan (shown as balance on the zed10fx) channel 1 all the way left and channel 2 all the way right.

EDIT - or of course into the 2nd stereo channel....

[BertKoor]

Maybe I still needed a bit of the "inside" knowledge of contruction of these cables

Page 29 of the User Guide maybe??

When you say a pair of TRS you mean the stereo channel dual "line-ins", right?

Correct

Although re-reading the manual they don't say if those line-ins are TRS or TS in the end

They don't state weather the two stereo line inputs are balanced or unbalanced indeed. In practice it won't matter that much anyway, since all combinations will produce sound without major issues.

[kpsychedelic]

Maybe buy the cables, connectors and a soldering iron and make your own ... it will probably help your understanding.

As a matter of fact that sounds like a great idea... will have it in mind...

So either use the cable that thecontrolcentre mentioned to go through the stereo channel or use a 3.5mm to dual 1/4" TS and plug into channels 1 and 2 (or 3 and 4) and pan (shown as balance on the zed10fx) channel 1 all the way left and channel 2 all the way right.

EDIT - or of course into the 2nd stereo channel....

Yes, but as a matter of fact I think I'll just use the same 3.5 to RCA and use a couple TS to RCA adapters (one TS that takes RCA as input) to use for the mono channels or the stereo but in the 1/4" inputs.

Maybe I still needed a bit of the "inside" knowledge of contruction of these cables

Page 29 of the User Guide maybe??

Hehehe I actually only came across that page last night by chance (don't know why I hadn't seen it), but anyway I was more referring to generally speaking, the construction of TS and TRS plugs, since they are not the same all the time.

They don't state weather the two stereo line inputs are balanced or unbalanced indeed. In practice it won't matter that much anyway, since all combinations will produce sound without major issues.

Ok, I will try both combos and see what feels better.

Anyway I think I finally grasped the basic concept and at least was able to make an inventory of the cables I need last night given to your valuable help guys, thanks a lot!!!

[MajorMuzik90]

Just became a new member, and Im new to the audio specifics as far as Hi z/ low Z theory. Was hoping to get a clearer understanding I currently own a telefunken copperhead, its listed as 100 Ω.. But came with a high z cable and power supply ...I have a Uad neve 1073 pre with Hi Z- Low Z feature...which would be the more optimum setting?

[aciddose]

Again:

"Z" means impedance. The symbol "Z" is a symbol, not a letter. Impedance is like in a water faucet: if you pinch the hose/close the faucet you increase the resistance ("impedance", "Z") and the flow ("current", "I") of the water is reduced until pressure ("voltage", "V") builds up to overcome the resistance.

In a guitar you have very little current ("I") available, so if you use a low impedance ("Z") input you'll be draining a lot of current and this will result in loading the pickups and tone circuits and likely you'll lose high frequency content: the signal will get low-pass filtered and decreased in voltage ("V"). At the same time however the radio signals and other EMI will also be loaded and filtered away.

If you use a high "Z" input you'll maintain the high frequency content and avoid loading the pickups or tone circuits... but the line will be unloaded and any radio signals or clicks (flipping light switches? starting the car?) will get picked up without being filtered.

There is no "optimum"... This is like you're asking us "I'm currently at the supermarket but I didn't bring a shopping list, what the optimum ingredients for lunch tomorrow?" Try them both, understand what the effects are and why they happen (do your research) and decide for yourself.

Professionals use dedicated buffer circuits (powered by 9V battery for example) close to the guitar. The loading is adjustable using a load resistor on the buffer input. The buffer will go into a low-Z cable and into the low-Z input: the buffer will provide plenty of current to drive the line and this will minimize the amount of EMI the line can collect on its way to the input circuit.

It's also possible to drive into a high-Z input from a buffer and intentionally introduce some specific loading at the input (on either the output or input ends, or both) to provide the best possible result. A buffer can also be designed to generate a balanced output for long lines that are sensitive to EMI.

Again: you'll need to understand the situation, the effects at play and their causes. Then you can decide what is the best solution in your particular situation.

[BertKoor]

Short answer: 100 ohm is low impedance. 100 k ohm would be high.

I have never seen a cable specific for high impedance. It's all coax to me.

[aciddose]

There are low/high Z cables that are useful for radio or in situations like with guitars. A low-Z cable is essential to avoid loading the pickups/tone circuit as I described.

That isn't important to consider when you use proper equipment like line buffers as I suggested.

[BertKoor]

Can you explain how one would know / notice a low-Z mic comes shipped with a high-Z cable?

[aciddose]

Short version: the cable has reactance (capacitor), impedence (resistor) and inductance (inductor) that interact with the circuits it is connected between. The two circuits and the cable connecting them become the complete circuit when they're connected together.

So the cable itself becomes an electrical component and has an influence on how the circuit behaves.

It's too much to type details, just look it up: https://en.wikipedia.org/wiki/Electrical_reactance (or slightly less useful, focuses on radio: https://en.wikipedia.org/wiki/Transmission_line )

You can find me explaining it multiple times here on KVR: influence of guitar cables on tone.

viewtopic.php?p=4933921#p4933921

Watch out for panty knots.

There are a ton of factors at play like the type of mic, which pickups you use, the tone circuit, type of cable, amplifier, length of cable, where it goes (if it passes through any other EM fields, "inverse square" remember, x = 1/d^2).

If you know all those numbers you can do the math and figure out exactly what the spectrum looks like, what the filters are, where their "cutoffs" are and how that changes as you change the circuit elements.

[BertKoor]

Thanks for typing all that, but it did nothing to answer my question.

[aciddose]

Then you're incapable of understanding how you'd measure the difference. Anything I could do to "simplify" the explanation would cause it to be wrong.

You need this information:

• the mic and any circuits contained inside it
• the sockets, plugs and cable and anything inside them
• the destination device "amplifier" or otherwise and the complete input stage circuit

With all that information you could then determine what effects could occur if any and exactly what they would be.

Without that information? You have nothing. It's 100% about information. You can't just make information out of nothing! The information you get to answer your question is simply all that information about the devices you're using mixed up and put back together in a different format. It's the same information.


If you wanted to change your question to: "how can I measure the properties of the cable?" and remove anything about the mic or the influence it might have:

You can get tools to measure those three properties of a cable and give you the numbers called "LCR meters". Inductance (L = Henrys), capacitance (C = Farads), and resistance (R = Ohms).

https://www.amazon.com/lcr-meters/b?node=5011684011

Those numbers would be useless on their own, but you could use them to compare cables... although you couldn't tell which is "better" or "worse" only if they're "different" or "identical".

If you understood the complete circuit you could plug in all the numbers including the numbers for the cable and get information about what influence the cable or different cables would have.

[aciddose]

With regard to "would know / notice":

This is concluded by using a "window" of parameters that have a high probability of being perceived.

This is usually: 20 Hz to 20000 Hz, 0 dB to -40 dB (1 to 1/100th) in ~1 dB steps.

So if for example one cable produces a second order (12 dB/o = 40 dB/d) low-pass filter with a "resonant peak" (Q > 1/2 ... Q > 1) and "cutoff" around ~1 kHz.

If another cable created the same filter but where Q was slightly lower such that at the same 1 kHz point the level was more than 1 dB lower: this would mean the effect would be considered likely, plausibly perceptible.

In most cases you'll see much larger differences like:
Cable 1) 1.2 kHz 0 dB peak
Cable 2) 0.9 kHz 4 dB peak

That isn't 100% certain to be "would know / notice" but it's likely >90%.

[BertKoor]

a telefunken copperhead, its listed as 100 Ω.. But came with a high z cable

So aciddose, wouldn't you agree this looks suspicious? How would the OP know about targeted impedance of the cable? Connector type? Paper label? Printed sideways? And what would the effect really be?