current digital to analog converter chip compatible with cirrus logic CS4390KSEP JNAWEA9834?

[Bernardo]

hello good morning everyone!
It turns out that I have an alexis DM pro that I don't want to part with (especially since the modern equivalents have outrageous prices).
It has a problem in the audio outputs, they all have a background breath that bothers me a lot, especially when I insert compressors to the individual outputs. I'm sure they are the digital to analog converter chip, they are from the Cirrus Logic brand with the superior nomenclature CS4390KSEP followed by JNAWEA9834. I think these chips are 24 bits and 2 channels. I don't know anything about these things that convert digital to analog and vice versa, I've never understood how they work.
My question is if someone can tell me if there are chips compatible with this that are current since these are from Cirrus Logic already. They are not manufactured and from what I have investigated they are quite bad.
Thank you very much and sorry for writing so long.

 

[scott2000]

It has a problem in the audio outputs

Shouldn't you suspect something there too or have you already investigated the output circuitry? What is breath?

 

[Bernardo]

Shouldn't you suspect something there too or have you already investigated the output circuitry? What is breath?

Sorry for the expression, "breath" "blew it.In Spanish it is the noise like air made by a device that is not in very good condition, a background noise that is not noise or tone, rather like a constant "sssshiiiiiiiiii". Sorry for my primitive way of explaining it.
I have changed all the electrolytics, regulators and reviewed most of the circuit, everything leads me to these converters, I have also researched on google and there are people who have experienced the same thing as my machine.

 

[scott2000]

If your search for a drop in replacement doesn't go well, I've had luck with this place before. Maybe you could reach out to them and see if they can help?

https://www.roseelectronicsinc.com/search.html

 

[abbey road d enfer]

Sorry for the expression, "breath" "blew it.

Commonly known as "hiss".

In Spanish it is the noise like air made by a device that is not in very good condition, a background noise that is not noise or tone, rather like a constant "sssshiiiiiiiiii".

Is it "siseo"?

 

[Newmarket]

Sorry for the expression, "breath" "blew it.In Spanish it is the noise like air made by a device that is not in very good condition, a background noise that is not noise or tone, rather like a constant "sssshiiiiiiiiii". Sorry for my primitive way of explaining it.
I have changed all the electrolytics, regulators and reviewed most of the circuit, everything leads me to these converters, I have also researched on google and there are people who have experienced the same thing as my machine.

You're saying there is a pattern of these devices developing this hiss / noise problem ?

 

[ccaudle]

from what I have investigated they are quite bad

The CS4390 was considered a pretty high quality converter when it was new. The converter devices are not exposed to any external interfaces, so it seems that something like the output buffers would be more likely to get damaged and go noisy than the converters.

Was it quiet when new, and has become noisy recently, or was it always noisy?
Is it continuously noisy, or only when playing a sample?

The CS4390 has a pretty high drive capability (rated for down to a 4k load), so you could make a capacitively coupled probe with an instrument input on a sound card, and follow the circuit from the output back to the DAC to see if you can tell if it suddenly gets noisier after one of the stages. Keep in mind that the DAC has symmetrical outputs but DC shifted, so there will be a differential-to-single ended stage, which may or may not have gain. Don't get fooled by level changes that are just caused by the expected gain of a buffer stage.

 

[Bernardo]

The CS4390 was considered a pretty high quality converter when it was new. The converter devices are not exposed to any external interfaces, so it seems that something like the output buffers would be more likely to get damaged and go noisy than the converters.

Was it quiet when new, and has become noisy recently, or was it always noisy?
Is it continuously noisy, or only when playing a sample?

The CS4390 has a pretty high drive capability (rated for down to a 4k load), so you could make a capacitively coupled probe with an instrument input on a sound card, and follow the circuit from the output back to the DAC to see if you can tell if it suddenly gets noisier after one of the stages. Keep in mind that the DAC has symmetrical outputs but DC shifted, so there will be a differential-to-single ended stage, which may or may not have gain. Don't get fooled by level changes that are just caused by the expected gain of a buffer stage.

Thanks for the explanation of the chip, could you tell me which components enter the output buffer? Is it some oamp like tl074? Isn't it strange that all 3 fail? I bought the machine second hand and I already had this problem so I don't know if it was a factory fault, I had some digital multi-effect comp yamaha rev500 p roland dep 3 that had "his"

 

[scott2000]

could you tell me which components enter the output buffer

Probably get an idea from looking at application notes of the chip. I looked real quick and couldn't find them.
Found this Lexicon uses the same chip. I wouldn't be shocked if the output set up had some similarities although I really don't know...

http://bee.mif.pg.gda.pl/ciasteczkowypotwor/#pro_audio/Lexicon/mpx500_svc_mnl_070-14399rv0.pdf

 

[Newmarket]

Thanks for the explanation of the chip, could you tell me which components enter the output buffer? Is it some oamp like tl074? Isn't it strange that all 3 fail? I bought the machine second hand and I already had this problem so I don't know if it was a factory fault, I had some digital multi-effect comp yamaha rev500 p roland dep 3 that had "his"

Not sure I understand. If you have investigated the circuit then you would know that ?

 

[ccaudle]

Isn't it strange that all 3 fail?

Three outputs on one machine? Or three different drum units? Are you sure it is a failure, and not just a limitation of the design of that model? Have you ever had one which you considered not noisy?

 

[Bernardo]

Three outputs on one machine? Or three different drum units? Are you sure it is a failure, and not just a limitation of the design of that model? Have you ever had one which you considered not noisy?

the alexis dm pro has 6 independent outputs, i seem to remember that it has 3 of these converter chips. I bought the unit second hand, I don't know if that noise is from the factory, possibly it is and I'm wasting time and I don't have much of a "pro".

 

[Bernardo]

Probably get an idea from looking at application notes of the chip. I looked real quick and couldn't find them.
Found this Lexicon uses the same chip. I wouldn't be shocked if the output set up had some similarities although I really don't know...

http://bee.mif.pg.gda.pl/ciasteczkowypotwor/#pro_audio/Lexicon/mpx500_svc_mnl_070-14399rv0.pdf

Thank you very much for all the information Scott, your help is always very valuable. I am going to investigate the output buffer and see what happens, perhaps the problem is the design of the model itself.

 

[radardoug]

It would be helpful if you could measure the noise level with a noise meter so we have an idea of how bad the problem is. A 24bit DAC should have a very low noise level. Having said that, if you are compressing after this device, then you will pull the noise floor up.

 

[ccaudle]

It would be helpful if you could measure the noise level with a noise meter so we have an idea of how bad the problem is. A 24bit DAC should have a very low noise level. Having said that, if you are compressing after this device, then you will pull the noise floor up.

The CS5390 is a late'90s 20 bit chip. It can have about a 105dB dynamic range best case, but the Alesis drum module has single ended nominal -10 dBV outputs, so probably not quite best case. Should still be at least as good as a CD player though. I would expect around 90dB dynamic range.

 

[ccaudle]

the alexis dm pro has 6 independent outputs, i seem to remember that it has 3 of these converter chips. I bought the unit second hand, I don't know if that noise is from the factory, possibly it is and I'm wasting time and I don't have much of a "pro".

You are setting max output level, right? You need to do that to maximize dynamic range.

You also never said what the outputs are driving. Have you verified the noise floor of whatever the drum module connects to?

 

[Bernardo]

but he jumped the 500 series preamp and connected the module directly to the ferrofish converter.
el ruido de fondo es el mismo, adjunto varias capturas de pantalla con alexis en el conversor y sin alexis en el conversor.
The 6 outputs have the same result in the analyzer and the listener

 

[Bernardo]

The oamps that lead to the continuation of the converter are TL082, sorry to mention the TL074, my memory is not the same as before.
It also has some LM339 but I think these control the triggers of the percussion pads

 

[abbey road d enfer]

TL082 is not the quietest opamp in the world, but in this position it should not be significant.
If all six outputs have the same noise, I would think either it's normal and there's not much to do, OR there is a problem that is common to all outputs and that may be a problem with the supply rails.

 

[Bernardo]

I changed all the electrolytics and regulators of the power supply, it was the first and the only thing I have done so far, but it seems that is what you say and that this device is that noisy.
thank you