Yes, I understand, of my 3 preamps all have xlr inputs and outputs, so I wanted to be able to use cables longer than 1.5 metres.
Thanks for your clarifications, they are much appreciated.
Of course it is not necessary, but highly recommended and makes sense. A chain is as strong as the weakest link.
I would not drive a 911GT3 with $200 tires. This is obvious.
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Indeed it is more complicated, doubles cost and space. I wanted to write "if he can build it", but that should be obvious
The absolutely highest end gear is always balanced and for a reason.
I see most people don't do the diodes as well, cause it makes it more complicated. But Nelson uses them, as there is a reason for.
If you use good chinch cables and have gear with properly engineered ins and out, you can use chinch cables much longer than 1.5m. Anything with low capacitance, resistance and proper shielding would do exceptionally. Check out for instance the Sommer Cable SC-Albedo MKII, just as an example.
No need for balanced (XLR) cabling between single ended gear in a normal user's home.
Also, having XLR ins/out doesn't necessary imply the gear is build balanced. Check this out, I have the feeling you don't really know.
Which amps are these, maybe someone here can help you identify?
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I do not enter into discussions involving technicalities outside my area of expertise, but I do not believe that reputable brands such as Mark Levinson, Accuphase and Audio Research insert balanced in/out connections just for marketing reasons. Having said that, I base this on my listening and comparing the different cables I found the balanced cables to be the ones that gave the best auditory results.
Then, as has already been said, in diyaudio, everyone believes they make their own masterpiece.
In any case, thank you again for your clarifying interventions.
Then, as has already been said, in diyaudio, everyone believes they make their own masterpiece.
In any case, thank you again for your clarifying interventions.
The proper way to use an XLR input in an amplifier is to use a proper summing circuit, or a transformer. That's not just marketing. There are distinct advantages to using a balanced connection, but only if properly summed inside the amplifier. This reduces overall distortion in the system, and eliminates common-mode distortion up to the last point in the chain that was fully balanced. Many preamplifiers are unbalanced, and only use a differential driver to create a balanced output, which is sort of pointless unless we're looking at long wiring runs (>10m).
What's marketing is if pin 1 and 2 are used, and pin 3 left open. You don't get any of the benefits of the balanced connector, and in fact pin 1 may carry more noise than the RCA shield. This sort of hack is pointless.
What's marketing is if pin 1 and 2 are used, and pin 3 left open. You don't get any of the benefits of the balanced connector, and in fact pin 1 may carry more noise than the RCA shield. This sort of hack is pointless.
I am not aware of any official Pass Labs or First Watt product which uses the diodes in parallel with source resistors. If there is one, I haven't noticed.
The schematic presented here uses the diodes as a concept, in order to increase current capability by bypassing the source resistors. There are alternatives to such a scheme and as I've mentioned before, the diodes can still be used with some other modifications to some of the component values.
Looks like you absolutely didn‘t understood what I‘ve written above. Mark Levinson and Accuphase are mostly build fully balanced, so yes they use balanced io. And yes, highest end audio gear is mostly build balanced as well. For myself I am running and building only fully balanced gear as I see advantages to it, separate chassis for the PSU‘s as well.
Bu,t if you expect balanced io to make your single ended, stereo, all in one chassis power amp to sound better only because of the XLR, you are most probably completely wrong.
Enough said.
It was not my intention to engage in controversy with any of the forum members, and I am not naive enough to believe that using an xlr cable will improve the sonic performance of an SE designed power amp, after it was made clear to me that the amp was designed for SE operation, the problem I'm facing is that of being able to use both XLR and RCA inputs and if there is a feasible way, I understand very well that what I want to achieve is a palliative that will certainly not improve the sound performance of the power amp, using the XLR input adapted to SE the sound performance will perhaps be worse or at most equal.
In any case, as things stand, I will only connect the RCA inputs to the FE board.
In any case, as things stand, I will only connect the RCA inputs to the FE board.
Hello members,
there are always arguments pro or contra balanced or single ended wiring in an audio system. So, I think we should
'cool' down a little bit.
Balanced interconnects are absolutely common in professsional audio (PA) because of its immunity against noise,
interference and other electrical 'trouble' ...
You could add a transformer or OPAmp (for example the THAT corp. 1606 and 1646 balanced line drivers and some extra circuit)
at the output of your audiogear to transform your audiosignal from single ended to balanced, transport the signal via XLR to the
next unit and bring the audiosignal back to single ended.
Is it worth the effort? Everybody has to decide on its own. For sure extra costs and perhaps extra trouble?
A really good article from Douglas Self: 'Balanced Line Technology'
http://www.douglas-self.com/ampins/balanced/balanced.htm
But I am getting completely off topic - this is the F5T illustrated build guide thread.
Have a relaxed Easter-weekend!
Enjoy the music
Dirk
there are always arguments pro or contra balanced or single ended wiring in an audio system. So, I think we should
'cool' down a little bit.
Balanced interconnects are absolutely common in professsional audio (PA) because of its immunity against noise,
interference and other electrical 'trouble' ...
You could add a transformer or OPAmp (for example the THAT corp. 1606 and 1646 balanced line drivers and some extra circuit)
at the output of your audiogear to transform your audiosignal from single ended to balanced, transport the signal via XLR to the
next unit and bring the audiosignal back to single ended.
Is it worth the effort? Everybody has to decide on its own. For sure extra costs and perhaps extra trouble?
A really good article from Douglas Self: 'Balanced Line Technology'
http://www.douglas-self.com/ampins/balanced/balanced.htm
But I am getting completely off topic - this is the F5T illustrated build guide thread.
Have a relaxed Easter-weekend!
Enjoy the music
Dirk
Once again I expressed myself wrongly, I meant that for the kit I bought and assembled and for my technical capabilities, I can only make an SE configuration.
@tricksters said that their pre-amp already has XLR outputs => I'll assume a differential signal. They've said that their run is (relatively) short at 1.5m. They just want to have both RCA and XLR inputs on the amplifier and experiment a bit, I believe. There was originally a bit of a misunderstanding on their part that a standard stereo F5TV2 would run balanced.
Converting balanced to SE and using an XLR jack at the input of the amplifier for an SE signal, is the current discussion, I think. @Sangram has listed some great pros and cons of ways to do that.
I think this post sums up their overall theme pretty well.
FWIW, I don't think anyone has engaged in controversy. I always learn a lot from everyone, and I hope none of my posts have come across as contentious. There are merits to running fully differential / balanced. I hope it never seemed like I was saying otherwise. That's why I continually was asking you WHY you wanted XLR inputs.
All the reasons have merit... some of them just deserve a bit more consideration, within each person's needs, IMO. Using a previous example... Sure, I'd drive a 911GT3 with $200 tires. I'm not on the track all the time... and some people will use a 911GT3 as a "grocery getter". I'd find it silly, but, it's their money. I'd also run it with lower octane fuel when not on-track... but that's me. I swap fuel, tires, engine mapping, suspension set-ups as needed for the purpose at hand. I also have a few cars. @starcat, I always love your posts. I'd love to hear your system; I'm sure it is impressive.
All the benefits for balanced / differential of which I am aware have been covered. The challenge (to me) is always weighing the pros against the cons. All things remaining equal, I'd have a fully balanced/differential chain from end-to-end in some cases. I also use an H2 generator, and I love it. To me, those concepts don't contradict each other.
Starcat listed some excellent cons. I added a few for consideration. I would never presume someone's level of ability. However, I've seen a number of builders far more talented than I struggle with this amp. In addition, this conversation started with what might be considered a fairly basic wiring question , which was shown incorrectly. It gave me pause. So... I did not immediately assume tricksters could successfully / easily build the more complex (IMO) balanced version. More importantly, I was wondering if they wanted or needed to build it. Perhaps I should have taken a different approach. Mea Culpa.
Back to the topic at hand... @tricksters
To be more concise (not my gift) ... IF your pre-amp(s) have both SE and XLR outputs they likely are already using one of a variety of circuits/components to go from differential to SE. Maybe they even have a nifty internal solution to go from SE to differential. Those solutions will likely depend on whether the selected input to the pre-amp is SE or balanced/differential along with whether the internal circuitry of the pre-amp is truly fully balanced / differential or not.
From what I've seen so far, my recommendation below is based on two things.
You want to use both RCA and XLR amplifier inputs for a SE signal and don't want to be lazy like me and potentially suffer from the previously stated downfalls. Like I said, I only do it on some builds.
Later, you may want to use XLR inputs for a differential signal and build another amp. This is low priority, but a consideration. You may want that 911GT3.
I'll also assume the following --
First ... let's call the new input on your amplifier XLR SE.
Next ... let's call all RCAs on amplifier or preamplifier RCA SE.
Then... let's call the XLR on the preamplifier, XLR Bal.
- You don't want to run RCA SE from your pre-amp to the XLR SE input on the amplifier. You could build a cable, but why?
- You want to run RCA SE from your pre-amp to RCA SE input on the amplifier. Obvious.
- You want to run XLR Bal from the pre-amplifier; convert it to SE properly; and use a XLR SE input on the amplifier. This seems to be your main concern part 1. This one makes the least sense to me, but there is a solution (IMO).
- You want to run XLR Bal from the pre-amplifier; convert it to SE properly; and use RCA SE input on the amplifier. This seems to be your main concern part 2.
My recommendation -
I'd build a single stereo amplifier (as designed) with a slight tweak. Add a female XLR input jack. Wire Pin 1 to the RCA tab / GND. Wire Pin 2 to the tip / signal. Ignore pin 3.
For the "balanced to SE converter" that you'll need to build or buy, use both an RCA SE and an XLR SE output. Same wiring as above. Ensure you label it properly, so you don't forget that your XLR output is not standard. The device will only have XLR Bal input.
That should meet all your needs... I think... maybe.
After the passing of many moons, you will have built some things, played with your new amplifier, tweaked your system to your heart's content, and listened to some wonderful music. Then, if you want balanced monoblocks; awesome! You already know how to build the amplifier. You'd build another identical one and do a relatively small rewiring job. Then, you'll either have a lot of fun or pull out all your hair. Why? Because, you'll have to get 2x2 amplifiers for the positive and inverted signals balanced out, the absolute and relative offsets nulled, and get the distortion profiles of the two monoblocks to match (if you care about such things).
But then.. you'd have a REALLY nice fully balanced / differential set-up. Once again... to me ... for this amp ... not worth it. For some... DEFINITELY worth it, but their needs and desires are different than mine ... or yours.
My goal is to see what YOU need and make a recommendation... not tell you what I like.
Mostly... enjoy your build process and the music.
Cheers!
my
May I suggest that instead of using an XLR but wired as if it a SE input, that the amp's XLR be wired to a high quality (Jensen 11P1 or equivalent Cinemag) line input transformer, so that the transformer converts the balanced input into a SE output? The output of the transformer is then connected to the input stage of the F5.
^ An exceptional suggestion. That would act as the "balanced to SE converter". However, the user has repeatedly stated that they would like to use an XLR cable / jack ... even after suggestions have been made that it is not ideal.
Perhaps your much more concise suggestion will carry weight. Cheers!
Perhaps your much more concise suggestion will carry weight. Cheers!
tricksters asked about some balanced to SE converters in post #1650
https://www.diyaudio.com/community/...rated-build-guide.254056/page-83#post-7317884
The LHS one looks like it's transformer based and may allow XLR / RCA input with the toggle of a switch. To my mind something like that built wth a high quality line transformer should satisfy his needs.
https://www.diyaudio.com/community/...rated-build-guide.254056/page-83#post-7317884
The LHS one looks like it's transformer based and may allow XLR / RCA input with the toggle of a switch. To my mind something like that built wth a high quality line transformer should satisfy his needs.
I did see that photo. The PCB on the right shows an active op-amp based converter and the PCB on the left uses very small 600/600 transformers, which also appear to be unshielded. That is why I suggested the Jensen transformer, which is shielded in a can and also appears to have much higher overload (inasmuch as the magnetic materials are much larger and therefore can accept more signal before reaching saturation. Another possibility is to the use the PCB on the left to take advantage of the input XLR and RCA jack mounting and the switching (assuming tricksters wants to have the option of both RCA and XLR balanced inputs), but wire in the Jensen transformers instead of the small 600/600 transformers. As this is DIY, tricksters has lots of options available.
^ Dennis and Halauhula - Agreed 100%... and already discussed as mentioned... the "difference" to the norm is using the SE signal output from such a device with an XLR jack for input to the amp vs. an RCA.
Again... I personally, don't think that's the best solution, and I've said so a few times... but...
Again... I personally, don't think that's the best solution, and I've said so a few times... but...
Nope, you can't run even a standard 911 with lower than 98 octane! And no, you can not put a $200 tyre on a 911GT3 as it is 20 and 21", as well wide and for a speed rating that not a single $200 tyre will fit that. It was engineered the way it is, so that it makes sense for the whole package as everything works together! And expect the ceramic brakes to match as well.All the reasons have merit... some of them just deserve a bit more consideration, within each person's needs, IMO. Using a previous example... Sure, I'd drive a 911GT3 with $200 tires. I'm not on the track all the time... and some people will use a 911GT3 as a "grocery getter". I'd find it silly, but, it's their money. I'd also run it with lower octane fuel when not on-track... but that's me. I swap fuel, tires, engine mapping, suspension set-ups as needed for the purpose at hand. I also have a few cars. @starcat, I always love your posts. I'd love to hear your system; I'm sure it is impressive.
The same applies to our other discussion. Things in the chain need to match, well it is good if they match
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^ You're fun. I can never tell when you're serious or just using hyperbole and analogies and having some fun. Always enjoy it... and you're always helpful, especially to me. However, you may want to look here if you really are talking about Porsches... I'm not doing this to point out an error. I don't care.
If you are trying to be factual.. update your facts. Cheers! Gotta run.
https://dealer.porsche.com/ca/oakville/en-CA/News-and-Events/Why-your-Porsche-needs-premium-gas
If you are trying to be factual.. update your facts.
Cheers! Gotta run. https://dealer.porsche.com/ca/oakville/en-CA/News-and-Events/Why-your-Porsche-needs-premium-gas