My DIY Amplifier has a small sizzling sound

Any cables suggestions?
I'm with Peter, any quadripolar electric cable (4x2.5mm) is perfectly fine: just connect together the poles on the opposite side (if you don't use biwiring).
As to biwiring, they are hard to find, but I use a quadripolar with different section, 2x2.5 mm on th LF and 2x1,5mm on the HF.
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Agree. I would not overthink the speaker cable thing. Far too much nonsense is written about this stuff. You just want something that does not affect the amplifier Zout, so the individual wires should be reasonably thick, and ideally not too capacitive or inductive. With the co-ax, you have to remember its LC is lumped, so you have an L element there are well - the amplifier is not just seeing the capacitive part of 250pF/metre as in Sevy's cable. In any event, any decently engineered amplifier should easily be able to drive a few hundred nano-Farads directly without breaking into any sort of sweat - make sure you have plenty of phase margin, use an output LR coupling network
(0.5-1.5uH//2.2Ohms) and a Zobel from the amplifier output rail to 0V (8.2 Ohms in series with 0.1uF), ideally on the amp module PCB to keep the loop area small.

I made all my cables - I use good quality gold plated banana plugs or spade connectors, thick cable like the one below from Amazon and then I feed a nylon sheath over the whole thing with heat-shrink and silicone sealer to secure everything at the ends. The thick cable on the back of the B&W 703's below I bought in Japan - the actual copper strand area is 5mm in diameter for each cable :cool:. As they say in these parts 'Its proper decent like'

(The RC networks on the back on the speakers are because I've been experimenting with cable termination - different subject)

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With the co-ax, you have to remember its LC is lumped, so you have an L element there are well - the amplifier is not just seeing the capacitive part of 250pF/metre as in Sevy's cable. In any event, any decently engineered amplifier should easily be able to drive a few hundred nano-Farads directly without breaking into any sort of sweat - make sure you have plenty of phase margin, use an output LR coupling network
(0.5-1.5uH//2.2Ohms) and a Zobel from the amplifier output rail to 0V (8.2 Ohms in series with 0.1uF), ideally on the amp module PCB to keep the loop area small.
So if I understand it right, 250pF/metre in my cable, versus "amplifier should easily be able to drive a few hundred nano-Farads directly", I don't have to worry, right?

And as for "use an output LR coupling network (0.5-1.5uH//2.2Ohms) and a Zobel from the amplifier output rail to 0V (8.2 Ohms in series with 0.1uF)", my actual design have that:

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So these professional 2.0mm2 ,15 AWG OFC cables shouldn't be problem... I bought them from a Professional Studio material company here in Montreal. I guess they know a bit about Professional gears...

http://www.economik.com/mogami/w3082-2c-14awg-superflex-coax-speaker-price-per-foot/

 
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Yes - assuming your amplifier feedback compensation is also good, you should easily be able to drive your cable. The output of your amp above looks good. When you test your amp, one of the things you have to do is spend a few hours with a range of capacitors from say 100pF up to 2.2uF in parallel with 2 Ohms, 4 Ohms, 8 Ohms, 33 Ohms, 100 Ohms and open circuit looking at the stability. This test is done at 2-3V pk-pk output squarewave at 2 or 3 kHz. You look for overshoot and any oscillation. I use LTspice extensively for loop gain analysis, but you always have to follow that up with extensive testing on the prototypes.

(You only really see very high capacitive loads on ESL's, but I test at 2.2uF because you never know if someone won't use an amp with an ESL)
 
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It doesn't matter what it says on it, it's still one of the worst ideas. 253pF/m
I really can't understand where all these crazy ideas come from and especially how the world accepts them. It's just audiophile nonsense.
W3082 cable was designed to have an appearance, size, and flexibility of a microphone cable, for very tight-space control room installation, yet still offer decent 15AWG copper cross section. Higher than usual capacitance/meter is an inevitable, perhaps somewhat unwelcome, consequence of its compact construction, rather than a "feature".
Mogami makes quality pro cables. It's unfortunate they had people who could have known better in marketing put out some silly snake oil style "customer testimonials".
I use 3173 for interconnects, analog and digital, and 3104 is my favorite speaker cable.
 
I made all my cables
I must also admit that I've never once bought a finished speaker cable :D

Back in the 1980s and 90s I used to be able to buy '79 strand' and Monster cables from the roll at HiFi shops, this was in the heady days before 'Cable-Woo', and the industry realising it was more profitable to sell cables and gold plated fuses... than to develop actual products :D
 
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I find it funny that the cables type question was address to sesebe because he was arguing my cable choice, and that everyone came with goods suggestions, except him... lol

Don't take it personally sesebe, I respect your choice ;-)
Well, I came up with a very good and to-the-point suggestion, but that was more or less ignored because was not audiophile.
https://www.diyaudio.com/community/...as-a-small-sizzling-sound.411503/post-7656725
In the same time when I made only a little comment that coaxial cable are not for speakers the storm has begun because it is a sensitive audiophile topic (speaker cables).
 
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...ignored because was not audiophile.
You seem frustrated with what you call "audiophile."

According to the dictionary, it just means:
"a person who is enthusiastic about high-fidelity sound reproduction"

https://www.merriam-webster.com/dictionary/audiophile

The word does not mean crazy or anything like that. It even kind of looks like you are interested/enthusiastic about rational high fidelity sound reproduction, so you might be a rational_audiophile?
Thus maybe you are using the word "audiophile" to mean "irrational audiophile" or something more or less like that?
 
An audiophile is a person who listens to devices instead of listening to music.
A person who loves music is not so interested in exactly how the music sounds, but is happy to listen regardless of the quality of the recording/playback and is more interested in the quality of the interpretation.
More something like this" Thus maybe you are using the word "audiophile" to mean "irrational audiophile" or something more or less like that?"