[howzz1854]

i think i saw this somewhere a while ago. but if anyone can confirm. Does STX/ST have a lower SNR at 192khz than 96khz? 

 

[germanium]

Quote:

i think i saw this somewhere a while ago. but if anyone can confirm. Does STX/ST have a lower SNR at 192khz than 96khz? 

That is true of pretty much all DAC's currently available. It is not really  major issue though as it is almost always within 1-2db of the best measuring 48KHz sample rate specs. A look at the specs of the DAC chips themselves will tell you that this is the case

 

[howzz1854]

Quote:

That is true of pretty much all DAC's currently available. It is not really  major issue though as it is almost always within 1-2db of the best measuring 48KHz sample rate specs. A look at the specs of the DAC chips themselves will tell you that this is the case

 
so do all of you listen at 24bit/48khz then? i know a lot of those debate are almost inaudible, but mostly to satisfy my psychological obsession. 

 

[xeizo]

Which settings to use is an endless debate, the only thing that is sure is using "default" is safe ie "sounds good" 

 
As to the aforementioned LME49990-kit on Ebay, I got my sample a few days ago and just found time to mount it. First, the long part of the legs had been bent during the transport so that it came off almost by itself on all legs. So, only thing left was short stumps which I managed to press in place using my fingers during several minutes. It felt fit, but the chips can possibly fall off during transport. When I switched on the PC I was seriously worried it shouldn't work, but it did. Both channels loud and clear, and with balance between them.
 
And the sound? I will come back to that after gaining impressions, but it sounds subjectively very good so at least nothing seems wrong. I have only listened through stereo HiFi-speakers so far. The absolutely first impression anyway is that the sound seems very dynamic and lively and lifts far off off the speakers, which may be a good thing as the default Xonar ST sounds a little flat in most respects. But I will know more later on!

 

[gr4474]

Hi I am new to this thread.  I have the Xonar STX and run 2 channel to an Emotiva UPA-200 amp.  I want to upgrade the op amps either to LME49990 or THS4032, and have read that I will need 2 opamp for headphones and 3 sets for the RCA.  Would I use THS4032's for both RCA and headphones?    Here's the link to the THS4032:http://www.ebay.com/itm/1PCS-TI-THS4032CD-THS4032-ON-DIP-ADAPTER-/221070742557?pt=LH_DefaultDomain_0&hash=item3378d7d41d
 
I want to buy the soldered 49990 from Frugalphile but I can't find him on Ebay.  Any link to where I can buy those pre soldered?

Thank you!

 

[gr4474]

Ok I found frugalphile!  Is this what I need? http://www.ebay.com/itm/DUAL-SOIC-LME49990-DIP8-ADAPTER-/190762476231?pt=US_Amplifier_Parts_Components&hash=item2c6a5462c7
 
Do I need 3, or 5 of these?  I still want to try the THS4032 and compare if you have a link to those soldered.  I am using the RCA outs, and not using headphones yet but plan to.  I have Sennheiser RS 170 Wireless and am considering 650's.

 

[xeizo]

Quote:

Ok I found frugalphile!  Is this what I need? http://www.ebay.com/itm/DUAL-SOIC-LME49990-DIP8-ADAPTER-/190762476231?pt=US_Amplifier_Parts_Components&hash=item2c6a5462c7
 
Do I need 3, or 5 of these?  I still want to try the THS4032 and compare if you have a link to those soldered.  I am using the RCA outs, and not using headphones yet but plan to.  I have Sennheiser RS 170 Wireless and am considering 650's.

 
That's the one I use, but I only have it in the buffer position, it works just fine and I still thinks it has enhanced the sound. In the other two postions, the I/V-positions, I have two LM4562NA/NOPB instead of the original JRC2114DD and as I said - everything works fine together.
 
I think the sound is awesome and I really feel like listening through large parts of my collection again. Very complex music with lots of overlays is what has had the largest benefit - "HiFi-demo" music already sounded good as it was; the resolution of detail is amazing while not being harsh, it's not a "dark" sound though so those who prefer that may beware. While not a dark sound signature, the bass is really deep and powerful
 
You would need one, as me, or a maximum of three to fill all positions. There are only three sockets on the card so you can't use more.
 
I only use the RCA:s too.

 

[gr4474]

Quote:

Probably not, you may aswell buy the Muses out of your own - works out the same. 
mmmm I actually can't help there.... I was busy testing buffers before my pc got taken out by lightening...... 
the AD797BR should work well - IF it doesn't oscillate, some members have got it to oscilate, and some have got it stable, I think the other opamps make a big difference, I think mine were oscillating in the I/V section. 
 
One thing is for sure - 3 THS4032 is just a bit too smooth. 

I'm confused, aren't 2 op amps for the RCA outputs, and 1 is for the headphones?  How are 3 too smooth?  What exactly do you recommend?
 
Thanks for all your help so far!

 

[gr4474]

Quote:

 
That's the one I use, but I only have it in the buffer position, it works just fine and I still thinks it has enhanced the sound. In the other two postions, the I/V-positions, I have two LM4562NA/NOPB instead of the original JRC2114DD and as I said - everything works fine together.
 
I think the sound is awesome and I really feel like listening through large parts of my collection again. Very complex music with lots of overlays is what has had the largest benefit - "HiFi-demo" music already sounded good as it was; the resolution of detail is amazing while not being harsh, it's not a "dark" sound though so those who prefer that may beware. While not a dark sound signature, the bass is really deep and powerful
 
You would need one, as me, or a maximum of three to fill all positions. There are only three sockets on the card so you can't use more.
 
I only use the RCA:s too.

Ok I ordered 3 LME49990's last night...I hope that's going to work because I didn't see your post that you only use 1. Should this be ok for all 3?  Wir3d said "3 THS4032 is to smooth" so I'm confused what to do.  Thank you for the reply!

 

[xeizo]

Quote:

Ok I ordered 3 LME49990's last night...I hope that's going to work because I didn't see your post that you only use 1. Should this be ok for all 3?  Wir3d said "3 THS4032 is to smooth" so I'm confused what to do.  Thank you for the reply!

 
I can only guess but I believe it will work ok since LME49990 is very similar to LM4562 in how it behave, just with lower distorsion, noise and slightly more power, and my LME49990:s works with two LM4562:s so it's not a very different config.
 
However, they also draw more power so let's hope the card can provide the juice. And, there is always a risk for oscillation when changing OP-amps sort of blindly like we do. What do oscillation do? Well, for one it draws even more power so if that would be the case the chips would get very hot. One thought is to test the config without the shield first with the sidepanel of the PC off, and try to determine how hot the chips actually get. Testing by holding a finger on top of them is probably enough to determine if they gets way too hot.
 
In case of actual oscillation I guess those more expensive adapters with condensators soldered on top of them would work better, but if it works anyway I don't see how those would be necessary.

 

[bcschmerker4]

Concerning the dual-surface-mount piggyback PCB for the JEDEC 8-pin DIP, the frugalphile version from eBay® appears to leave no room for any components that may be needed for Balance/Input Compensation on the National Semiconductor®/Texas Instruments® LME49990MA; but the Output Compensation is readily accessible, even if I have to hurdle the 49990MA's +Vcc pin.  Any better designs available for the adapter PCB itself?


 

 

[cdd3068]

Quote:

Ok I ordered 3 LME49990's last night...I hope that's going to work because I didn't see your post that you only use 1. Should this be ok for all 3?  Wir3d said "3 THS4032 is to smooth" so I'm confused what to do.  Thank you for the reply!

 
I only replaced the two opamps...however... I only use the headphones, not line out. 

 

[xeizo]

Quote:

 
I only replaced the two opamps...however... I only use the headphones, not line out. 

 
Yes, afaik that would do, just like myself gives priority to the single bufferamp socket since I only use the RCA:s .... things may be more complex, but I haven't found any good information on how those three opamps affect each other ....

 

[howzz1854]

can some of you make a recommendation on what OPamp to try out next. 
 
i ordered a pair of LME49720 and i wasn't quite impressed. it killed the bass. 
 
i am listening through HD598, which is what i consider bass neutral.
 
what i look for MOST is soundstage, and bass second. so if there is one opamp out there with great soundstage but doesn't sacrafice bass, or improves on it, i'd love to give it a shot.  thoughts would be deeply appreciated.

 

[nicholars]

Anyone know if the STX headphone amp works well with Sennheiser IE8 IEM's?
 
It says 10ohm output impedance and the IE8 are 16ohm so only 1.6x the output impedance?