Hi Marchel,
Is this the mod mentioned by scateo? I haven't tried it yet.
To be honest, I'm quite new at soldering so I'm always afraid, but this seems easy enough. Do you know what is the purpose of the resistor? If it's for protection, I might have to think about it. (I've had a bad experience with RCA connectors and broken equipment before)
I'm actually in the process of making some pretty big changes in my system. So I'll probably wait until the dust settles and see how everything integrates together before trying anything which requires a soldering iron to reverse.
If you put it that way, I'll definitely have to try the AD797 along with the OPA627 for the output stage. Shipping will probably take weeks, but I'll let you know the results.
My 4x AD797 arrived!! (I ordered yesterday from Digikey and got it today...now that is beyond FAST and I'm in Canada! )
My impressions so far closely mirror Marchel's. I doubt I can articulate the differences better than he did, so I won't bother. Suffice it to say, the changes are pretty big in a very good way! I might not even bother with OPA627 on the output stage depending on how I feel after the honeymoon is over.
Marchel, thank you for the lead/tips on AD797. Best $35 I've spent on audio in a while. I'm getting all giddy just thinking about it
Zipperdog, I do think the soundstage is a significant strength of this dac. Take what I say with a grain of salt as I don't do a lot of "critical" listening, I don't have experience with many different dacs, and my speaker placement leaves a lot to be desired. But in general, I find the Wolfson has a more involving, 3d soundstage than my old dac. The instruments are more believable and layered. In fact, this was the main thing I noticed right out of the box. Of course, given the issues I've mentioned above, it's hard to say if it's good relative to my old dac or in absolute terms, or perhaps it could even be willful thinking.
)My impressions so far closely mirror Marchel's. I doubt I can articulate the differences better than he did, so I won't bother. Suffice it to say, the changes are pretty big in a very good way! I might not even bother with OPA627 on the output stage depending on how I feel after the honeymoon is over.
Marchel, thank you for the lead/tips on AD797. Best $35 I've spent on audio in a while. I'm getting all giddy just thinking about it
Zipperdog, I do think the soundstage is a significant strength of this dac. Take what I say with a grain of salt as I don't do a lot of "critical" listening, I don't have experience with many different dacs, and my speaker placement leaves a lot to be desired. But in general, I find the Wolfson has a more involving, 3d soundstage than my old dac. The instruments are more believable and layered. In fact, this was the main thing I noticed right out of the box. Of course, given the issues I've mentioned above, it's hard to say if it's good relative to my old dac or in absolute terms, or perhaps it could even be willful thinking.
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Hi Marchel,
Is this the mod mentioned by scateo? I haven't tried it yet.
To be honest, I'm quite new at soldering so I'm always afraid, but this seems easy enough. Do you know what is the purpose of the resistor? If it's for protection, I might have to think about it. (I've had a bad experience with RCA connectors and broken equipment before)
Hi, Sorry for the late reply.
I've studied the datasheet of the opamps that we use, And they are short circuit protected, The datasheet does not even suggest a series resistor in the output, So I'm not sure what they are really for, A safety net perhaps.
But even if you manage to destroy an opamp by short circuiting the output, They are easy to replace, And the sonic improvement you will enjoy by doing the tweak, Far out weighs the the supposed safety net the resistor offers.
The best and safest way in connecting and disconnecting components is with the plug, unplugged.
I just received the OPA627, But I have to return them, Because both are defective, Both run very hot , with very faint output, And one of them have + 12v on the output and another have about -11v, Luckily My TKD volume pot in my Pass B1 pre did not get damaged. I tried cleaning the contacts and placed back the opa627 ,same result. I replaced my AD797 and the OPA134, Both are good. I sent back the OPA627.
OTOH, I just ordered a pair of LME49710.
OTOH, I just ordered a pair of LME49710.
Lordearl, how did you find the LME49710s? I'm looking forward for your impressions. Did you get a chance to try AD797 for the filter stage yet?
Marchel, I'm sorry to hear the OPA627 gave you trouble. Did you order from ebay or a reputable reseller? (I'm debating this myself as the costs on ebay are a LOT cheaper, but I would have to worry about issues regarding authenticity etc.)
I still haven't tried the mod yet. I have a bit too much on my plate right now. I'm trying to finish a TA3020 kit and a speaker kit I purchased a while ago. My first time doing such projects...so it's been quite a journey
Marchel, I'm sorry to hear the OPA627 gave you trouble. Did you order from ebay or a reputable reseller? (I'm debating this myself as the costs on ebay are a LOT cheaper, but I would have to worry about issues regarding authenticity etc.
)I still haven't tried the mod yet. I have a bit too much on my plate right now. I'm trying to finish a TA3020 kit and a speaker kit I purchased a while ago. My first time doing such projects...so it's been quite a journey
Hi,
My opa627 looks authentic, It is laser marked but looks old stock, The seller offered to send me another pair for free, Even if I don't return the defective pair. But I declined to that offer and opted to send back the opamps instead, For a refund. The seller have 99% plus feedback.
The LME49710 seems to equal if not surpass the opa627 in terms of SQ anyway, At least that's what I've read.
If the seller says on his/her ebay ad that the Opamp is genuine or orig, and the price is not far off, There is a big chance that they really are genuine. I don't trust those that sell these opamps so cheaply and doesn't give assurance of authenticity in their ad.
I've bought the lme49710 from here eBay.ph: LME49710 Single HiFi Audio OpAmp AUTHENTIC; LME49710NA (item 150458088551 end time Jul 20, 2010 17:39:40 PHT). It cost 3.96usd cheap, But then this opamp is in reality cheap, As I've read that one can order it for a minimum quantity of 350pcs for 1 usd each, So the price for retail seem to be ok. Fingers crossing.
My opa627 looks authentic, It is laser marked but looks old stock, The seller offered to send me another pair for free, Even if I don't return the defective pair. But I declined to that offer and opted to send back the opamps instead, For a refund. The seller have 99% plus feedback.
The LME49710 seems to equal if not surpass the opa627 in terms of SQ anyway, At least that's what I've read.
If the seller says on his/her ebay ad that the Opamp is genuine or orig, and the price is not far off, There is a big chance that they really are genuine. I don't trust those that sell these opamps so cheaply and doesn't give assurance of authenticity in their ad.
I've bought the lme49710 from here eBay.ph: LME49710 Single HiFi Audio OpAmp AUTHENTIC; LME49710NA (item 150458088551 end time Jul 20, 2010 17:39:40 PHT). It cost 3.96usd cheap, But then this opamp is in reality cheap, As I've read that one can order it for a minimum quantity of 350pcs for 1 usd each, So the price for retail seem to be ok. Fingers crossing.
OK done some good listening with the LME49710NA at the output and to be honest, there's very little difference.
It's a very balanced opamp & gives slightly better definition in the bass - but you lose that "made for rock music" feel you get with the OPA627.
There's not too much to add, save to say that it's worthwhile taking as an upgrade to the OPA2134. In fact, I'd say that the OPA2134 + OPA49710 is a good combo - and the price of the chips is about the same.
One thing I did notice is that there seems to be less gain ... Marchel you might be able to measure this when you do the switch. Another point would be that I find it REALLY shows up bad recordings. I quite enjoyed listening to Pink Floyd's ANIMALS with the OPA627, but the LME49710 shows the layer of silt that sits on top of the sound in that cd.
My next step will be to add a pot in here so I don't need a preamp any longer.
Anyone have an idea as to which pot will be best?
It's a very balanced opamp & gives slightly better definition in the bass - but you lose that "made for rock music" feel you get with the OPA627.
There's not too much to add, save to say that it's worthwhile taking as an upgrade to the OPA2134. In fact, I'd say that the OPA2134 + OPA49710 is a good combo - and the price of the chips is about the same.
One thing I did notice is that there seems to be less gain ... Marchel you might be able to measure this when you do the switch. Another point would be that I find it REALLY shows up bad recordings. I quite enjoyed listening to Pink Floyd's ANIMALS with the OPA627, but the LME49710 shows the layer of silt that sits on top of the sound in that cd.
My next step will be to add a pot in here so I don't need a preamp any longer.
Anyone have an idea as to which pot will be best?
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Hi Lordearl,
My dac originally came with opa134, And i've read that it is supposed to be a newer version of the opa132, And based on this link Notes on Audio Op-Amps They are closely related and should sound similar . I don't supposed they would do justice to the 4 wm8740's inside.
Re: Potentiometer, There are plenty to choose from, But I'd definitely recommend the TKD pots, Expensive though at around 70USD. Very transparent sounding with deep soundstage , And nearly equals my high end remote controlled relay based dual mono attenuator in terms of imaging. The less expensive Noble and Alps should also be good, Based on what I've read . But I have no experience with either in the same circuit, So I can't compare the two.
My dac originally came with opa134, And i've read that it is supposed to be a newer version of the opa132, And based on this link Notes on Audio Op-Amps They are closely related and should sound similar . I don't supposed they would do justice to the 4 wm8740's inside.
Re: Potentiometer, There are plenty to choose from, But I'd definitely recommend the TKD pots, Expensive though at around 70USD. Very transparent sounding with deep soundstage , And nearly equals my high end remote controlled relay based dual mono attenuator in terms of imaging. The less expensive Noble and Alps should also be good, Based on what I've read . But I have no experience with either in the same circuit, So I can't compare the two.
done a bit of research on the volume levels & have a rough idea, but if I play some quiet music with the DAC straight into the power amp, there's some noticeable background noise in the speakers. this was lessened somewhat when I changed the output opamps from 627 to 49710 (which has a higher PSRR), but still makes me think it may well need another buffer between the dac and power amp
Hi,
I've been listening to the LME49710 for a few days now, They are at the output stage of the dac, I'm using AD797 at the filter stage. I've exchanged between the LME49710 and the AD797 at the output stage for maybe 5 times, And switched between two preamps a few times in my system ,In the time that I have the LME49710. So that I could carefully verify the difference in SQ between the two.
Well , I'll just describe what I'm hearing, Let me just say that the difference in sound quality is apparent. First of all there is the difference in highs, The AD797 have a crystalline quality and sheer transparency when dealing with sibilance, It just sound so natural like it (The AD797) is not there in the circuit, Wheres as in the LME49710, The highs, Though good by general standard ,And much better( I presume) than the old opamps like JRC5532 the likes, That I heard in other electronics before. The highs still have some graininess which makes sibilance sound a little hard or accentuated and it also seem to have this subjective high freq limit to the sound, Which also resulted in loss of sound-stage depth, Even when my preamps' load are pretty benign , One is 47K the other is 250K load. I'm not implying that the LME49710 sounds struggling though, In fact the LME49710 sound more dynamic especially in the bass.
The bass is where the difference is even more apparent, So apparent that I have to turn down the volume of my sub-woofer after I changed to LME49710 form AD797, The LME's bass sounds louder than the 797, But I can't comment whether which one is better in this regards , Because there is vast difference in taste amongst listeners , When it comes to bass quality, But I can describe the difference between the two, The bass in 797 sounds softer even when the sub's volume is turned up a bit, Where as the bass in the LME sounds loud and have this thumpy quality , Even when the sub's volume is turned down a bit.
The midrange is just about equal, Neither is too forward nor too laid back , I think they are just right , And the imaging is just about equal too, It is just that the LME49710 have less deep sound-stage due to the high frequency difference mentioned above. By comparison, The OPA134 is more laid back especially in the upper midrange.
I was really hoping that the LME49710 would equal or exceed the AD797's sound quality , Cause the AD797 is kinda expensive, And I like to use cheaper alternatives in my other projects , But it did'nt, So all in all, I think the AD797 is a clear winner here, And I really recommend it to be used on this Dac, Both in the filter stage and output stage. You should try it, I'm pretty sure you will not be disappointed.
I've been listening to the LME49710 for a few days now, They are at the output stage of the dac, I'm using AD797 at the filter stage. I've exchanged between the LME49710 and the AD797 at the output stage for maybe 5 times, And switched between two preamps a few times in my system ,In the time that I have the LME49710. So that I could carefully verify the difference in SQ between the two.
Well , I'll just describe what I'm hearing, Let me just say that the difference in sound quality is apparent. First of all there is the difference in highs, The AD797 have a crystalline quality and sheer transparency when dealing with sibilance, It just sound so natural like it (The AD797) is not there in the circuit, Wheres as in the LME49710, The highs, Though good by general standard ,And much better( I presume) than the old opamps like JRC5532 the likes, That I heard in other electronics before. The highs still have some graininess which makes sibilance sound a little hard or accentuated and it also seem to have this subjective high freq limit to the sound, Which also resulted in loss of sound-stage depth, Even when my preamps' load are pretty benign , One is 47K the other is 250K load. I'm not implying that the LME49710 sounds struggling though, In fact the LME49710 sound more dynamic especially in the bass.
The bass is where the difference is even more apparent, So apparent that I have to turn down the volume of my sub-woofer after I changed to LME49710 form AD797, The LME's bass sounds louder than the 797, But I can't comment whether which one is better in this regards , Because there is vast difference in taste amongst listeners , When it comes to bass quality, But I can describe the difference between the two, The bass in 797 sounds softer even when the sub's volume is turned up a bit, Where as the bass in the LME sounds loud and have this thumpy quality , Even when the sub's volume is turned down a bit.
The midrange is just about equal, Neither is too forward nor too laid back , I think they are just right , And the imaging is just about equal too, It is just that the LME49710 have less deep sound-stage due to the high frequency difference mentioned above. By comparison, The OPA134 is more laid back especially in the upper midrange.
I was really hoping that the LME49710 would equal or exceed the AD797's sound quality , Cause the AD797 is kinda expensive, And I like to use cheaper alternatives in my other projects , But it did'nt, So all in all, I think the AD797 is a clear winner here, And I really recommend it to be used on this Dac, Both in the filter stage and output stage. You should try it, I'm pretty sure you will not be disappointed.
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Hi lordearl,
I think you're gonna need a proper preamp for this , As I'm not experiencing any noise problem form this Dac, It might be that the attenuator you use is not properly shielded or grounded, Or the impedance is too high. Or it could be ground-loop in your system, But I'm just guessing here at best. As I haven't seen your system and how it is connected from the ac line. The Pass B1 buffer preamp is the one I tested and I highly recommend for this dac, It is easy build, And you don't have to worry about loss in transparency , Cause this preamp is very transparent, As transparent as transparent can be. Just make sure it is placed in a proper chassis. Building a passive preamp for this Dac might prevent it from sounding it's best due to impedance mismatch.
It's available again! (Link)
I recently tried a m2tech Hiface with the DAC (just today actually.) I never knew I was missing out on so much! The difference was really night and day. The first thing I noticed was more/better bottom end. It sounded palpable as though it had texture! Vocals seemed more natural (it always sounded a bit thin before). There are more details, increased clarity, and the soundstage became more 3d (The Wolfson + the Hiface combo are really leagues above my old setup in this regard) . It was simply beautiful. I haven't sat down and just listened for a while and today I just couldn't myself. (*Note: Take the above with a grain of salt. It IS my first day with the Hiface and I have yet to switch back to USB for some A/B'ing)
OTOH, I do feel some parts of the music can be more refined. Sometimes I think the Hiface is either not resolving the details cleanly or not presenting them perfectly. I can't really put a finger on it. But I suppose it is possible that by improving the most glaring issues in my system, the Hiface has alerted me to some other area I didn't notice before. I am also getting a slight pop/clip every time I manually switch songs on Foobar (using KS).
On another note, I still haven't changed my output opamps. I can't decide between the ADA797s or OPA628s
I recently tried a m2tech Hiface with the DAC (just today actually.) I never knew I was missing out on so much! The difference was really night and day. The first thing I noticed was more/better bottom end. It sounded palpable as though it had texture! Vocals seemed more natural (it always sounded a bit thin before). There are more details, increased clarity, and the soundstage became more 3d (The Wolfson + the Hiface combo are really leagues above my old setup in this regard) . It was simply beautiful. I haven't sat down and just listened for a while and today I just couldn't myself. (*Note: Take the above with a grain of salt. It IS my first day with the Hiface and I have yet to switch back to USB for some A/B'ing
)OTOH, I do feel some parts of the music can be more refined. Sometimes I think the Hiface is either not resolving the details cleanly or not presenting them perfectly. I can't really put a finger on it. But I suppose it is possible that by improving the most glaring issues in my system, the Hiface has alerted me to some other area I didn't notice before. I am also getting a slight pop/clip every time I manually switch songs on Foobar (using KS).
On another note, I still haven't changed my output opamps. I can't decide between the ADA797s or OPA628s
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