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Hi,
Anybody knows what kind of D/A converters PA2x has?

King Korg wrote:Hi,
Anybody knows what kind of D/A converters PA2x has?

Cirrus Logic CS4398-CZZ

See the specs here ...

http://www.cirrus.com/jp/pubs/proDatash ... 398_F1.pdf

Thoraldus wrote:

King Korg wrote:Hi,
Anybody knows what kind of D/A converters PA2x has?

Cirrus Logic CS4398-CZZ

See the specs here ...

http://www.cirrus.com/jp/pubs/proDatash ... 398_F1.pdf

Thank you for your answer,I have searched on the internet but I didn't find anything,I don't know where you found the information.

The reason I asked for is because some people blame Pa2 converters for the "cold sound" compared to Tyros 4.I don't know what kind of converters use Tyros 4 but I don't think they are responsible for that "soft sound" of Yamaha.

I like Korg sounds for some styles, but for other styles (ballads for exemple) I would like to sound like Tyros.

I want to try to connect a compressor (with mastering settings) like RNC at the PA2 output to see if I can get something close.I already use a BBE Sound Maximizer after PA2 and the sound improvement is huge.

King Korg wrote:

Thoraldus wrote:

King Korg wrote:Hi,
Anybody knows what kind of D/A converters PA2x has?

Cirrus Logic CS4398-CZZ

See the specs here ...

http://www.cirrus.com/jp/pubs/proDatash ... 398_F1.pdf

Thank you for your answer,I have searched on the internet but I didn't find anything,I don't know where you found the information.

[snip]

That information and much more is in the PA2X Service Manual.

Hi Thoraldus,

Can you send me the PA2X Service Manual?

I'm looking for this document for the PA2X repair.

My e-mail: alexsirotnik at gmail dot com.

Your help will be highly appreciated.

Hi Doctor, the Pa2x converter is excellent, I saw the specs and much better as the converter used in the Pa500. Cirrus Logic develops one of the best converters family of the market. Some highlights of this converter CS4398 type that shows its excellent performance, 120db of dynamic range and differential outputs is a superb feature:

Advanced multibit Delta-Sigma architecture
120 dB dynamic range
-107 dB THD+N:
Differential analog outputs

The question about sound quality is very complicated. Good quality starts on the wave ROM samples. The multi sample technique used to record the real instruments sounds which involves mics placement, the instruments in used and the ability of the music guys to play each of the sounds notes, the patch creations, post editing of samples applying effects and normalization of dynamic range, etc plays an important role on the final sound quality. Next this comes the PCM DSP sound engine (HI synthesis, EDS, etc) and today the type of DSP in use doesn´t matters because this type of devices are very advanced. The last part and most critical is the quality of the DAC in use and post stages design. Today all the devices in use (DACs and operational amplifiers) are excellent in quality. With 24 bit of resolution the lost of dynamic range and resolution due increased polyphony on a performance is avoided. So the real problem that I see on most keyboards is a wrong design on the analog stages after DAC, starting on some cases on the 2nd order LPF (low pass filter) and design of the operational amplifiers stages.

I have a blog explaining the issue that I found on the Pa500
www.alfredoblogspage.blogspot.com

Again there are no easy solutions regarding the sound quality of an digital instrument or recording device. A careful design from manufacturer engineering following the standards is the key to avoid users dissatisfaction / complains about quality. And discard the DACs as the root cause of a bad quality sound, today such devices are excellent in performance and specs.

Regards.

Thoraldus wrote:

King Korg wrote:

Thoraldus wrote: Cirrus Logic CS4398-CZZ

See the specs here ...

http://www.cirrus.com/jp/pubs/proDatash ... 398_F1.pdf

Thank you for your answer,I have searched on the internet but I didn't find anything,I don't know where you found the information.

[snip]

That information and much more is in the PA2X Service Manual.

Can you send me the PA2X Service Manual?

alfredokiwi
It's absolutely true that DAC's high quality is determined primary of well designed filters and their
peripheral high tolerance components like low SN ratio op-amps ,high quality metal film carbon
resistors and mica or tantalum capacitors , since logic circuits of 16/24 bit converters & features are
almost the same with a common home CD player !

Cirrus Logic as standalone without scientific complex filter design like
7 Pole Chebyshev filters , means just nothing !

AntonySharmman wrote:alfredokiwi
It's absolutely true that DAC's high quality is determined primary of well designed filters and their
peripheral high tolerance components like low SN ratio op-amps ,high quality metal film carbon
resistors and mica or tantalum capacitors , since logic circuits of 16/24 bit converters & features are
almost the same with a common home CD player !

Cirrus Logic as standalone without scientific complex filter design like
7 Pole Chebyshev filters , means just nothing !

Yes I agree but the specs from CS4398 are excellent because this converter is on the top of the list !!. Manufacturers put measurements on datasheets about the performance of their devices and a 2 or 3 pole DAC filter is well enough for filtering digital artifacts, more filtering quality will increase costs without benefits. I think that a "good dynamic range" is the most important aspect on a keyboard/arranger and next the quality of PCM samples. Because a keyboard is basically a PCM sampler/ digital mixer with real time effects the overall mix of voices/patchs will determine if sounds good or not.

I can´t complain the quality of the Pa500 after circuit changes, all explained on my blog. Because Pa500 factory dynamic range was to poor for a professional performer I decided to correct it. And maybe other keyboards/arrangers are affected in the same way

Here´s my blog link explaining the Pa500 issue:

www.alfredoblogspage.blogspot.com.ar

Regards.

hundreds of companies that produce High-End Hi-Fi audio equipments for decades
announce the same extraordinary specs and you can never listen even to close
results of each of them , same happens here !
I know for sure that this second-order Butterworth filter that Cirrus Logic proposes
is insufficient (not to mention poor designing), since I design op-amps for 20 years !
If you own an Apogee DA-16X like me , try to explore it to see what is the art of filter designing !

I'll give you an example ,when I was imported a HQ ambient DK multisample in Pa2X Pro
and then I connected digital output to Apogee DA-16X ... audio improvement
,compared to Pa2X internal DAC ,was Huge , though both DAC specs were too close !
See what I mean !!!

AntonySharmman wrote:hundreds of companies that produce High-End Hi-Fi audio equipments for decades
announce the same extraordinary specs and you can never listen even to close
results of each of them , same happens here !
I know for sure that this second-order Butterworth filter that Cirrus Logic proposes
is insufficient (not to mention poor designing), since I design op-amps for 20 years !
If you own an Apogee DA-16X like me , try to explore it to see what is the art of filter designing !

I'll give you an example ,when I was imported a HQ ambient DK multisample in Pa2X Pro
and then I connected digital output to Apogee DA-16X ... audio improvement
,compared to Pa2X internal DAC ,was Huge , though both DAC specs were too close !
See what I mean !!!

The same converter used on the Pa500 an AK4384 is used on the Korg R3 (MicroKorg XL should use the same). If the well acclaimed R3 use it means that sounding quality is achieved by this converter in other words the AK4384 is not a bad converter. I don´t know if the M50 use the same type, models who use a better converter are the M3 (PCM1793) and Pa2X (CS4398), both converters with differential analog output.

On the Korg R3 I have twice the line output level because most of the patches are not so loud on output volume sounding a little weak. After changes to control the gain I use the R3 volume knob as attenuator in case of to much output level. In other words is better to have more gain and in case of over level reducing it with the volume knob because it acts as a passive attenuator before last op amp stage and a passive component don´t adds noise. From technical perspective the last operational amplifier stage on the Korg R3 was factory set at unity gain and for me this approach is not recommended...., I prefer to have some gain on every stage (set to 2,2 after circuit changes) because each stage adds some noise floor and at unity gain you will have the same output level plus stage noise, so is always better to set each stage with a degree of amplification/gain.
I performed the circuit changes on the R3 to avoid the need of increase the gain on the mixing console because this method of more gain on the console to push up volume level increase the recording noise floor on the mix.
I will see to add some audio demos about the new R3 sound quality because dynamic range is improved to.

The Korg TR is OK on its factory output levels because last stage has an amplification factor of 1.1 a bit low I think but OK to avoid the add of stage noise floor, no complaints about it.