Not wishing to keep you from trying whatever you like.
Neither TCR (thermal coefficient) nor inductance (the tiny amount we are talking here) would have any negative effect in the circuit for those resistors. Now more than 1uH or so I would be worried.
Now if you put some boutique resistor in there and love it, well more power too you.
Russ I was greatly impressed how sounds the Legato with the standard parts. Possible the 15nF teflon film & aluminium foil 1% caps are a big upgrade so I start to look for other possible critical parts like are the resistors, which are the others resistors not rated 1W more criticals? or do you have another idea to upgrade the Legato?
100 is too high if you decided to use passive I to V. Distortion figures will suffer…
with active, OP based I to V, better result could be obtained with OP's with lower than 627 input bias current specs because the OP's bias current compare directly with DAC's current LSB... so it becomes a factor at 24bit resolution... in particular if the ground topology, adequate decoupling / voltage rails regulation can provide low noise conditions. Without too much checking, I think twisted pair I to V boards could be used with 1704's but only in dual differential configuration (4 X 1704's for both channels).
There are posts around here and “over there” that explain in detail I to V conversion for single 1704 per channel…
Cheers,
Boky
I know what is TCR (temperature coefficient resistance) so is the value expressed in ppm the resistor can change with the temperature BTW thanks to remember me
Also I know that current noise is expressed in mV or uV over the audio bandwith not in ppm
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Well, I wouldn't be categorical about anything someone else would hear. Personally I wouldn't expect the CCS resistors to make much if any difference, provided they are decent quality - which the Dales are. But of course no one should stop you experimenting if you want to find out for yourself!
Re. the Vishays, yes, I'm planning to try out some TX2575 at some point myself for I/V. They measure exceptionally well, which seems to correlate with anecdotal reports of their sound, so they are worth trying IMO.
Sorry, forgot to reply. My tweeters are Fountek ribbons, and I also have some Grado SR80i headphones. Not sure why that's relevant though?
Well, I wouldn't be categorical about anything someone else would hear. Personally I wouldn't expect the CCS resistors to make much if any difference, provided they are decent quality - which the Dales are. But of course no one should stop you experimenting if you want to find out for yourself!
Re. the Vishays, yes, I'm planning to try out some TX2575 at some point myself for I/V. They measure exceptionally well, which seems to correlate with anecdotal reports of their sound, so they are worth trying IMO.
Hi Dan
I used Vishay S104D resistors for I/V as they have a current rating of 1W and TX2575 as output resistors (for SE) All I can say is my Legato sounds damned good.
I'm slightly confused as to whether 1W is necessary for the I/V resistors. If not then the TX2575 would be excellent otherwise consider the S104D's they work very well I think. To my ears there was an improvement.
Vishay (Texas components) make the Z foil version S104Z @ 1W, which would be even better but a bit pricey.
I'm sure you won't be disappointed whatever you choose. If you want I can give you the prices I was quoted for various types.
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Can be Audio Note 1% 1/2W, I don't know any source with stock 1K 1/2W or 1W for Shinkoh, I only know HIFICOLLECTIVE UK with 2W but can recommend you because are very big.
BTW Audio Note tants sonically speaking aren't the same like Shinkoh tants.
Since the talk was swirling around "glassy sound" and high pass filtration, etc., I just wondered if maybe you were a full-range advocate. ...since many of those implementations roll off on both sides... When talking about what we hear, and each us of is obviously different, we tend to assume that our speakers and acoustics are 'reference'. I know MINE are!
No seriously, BII SQ and pre-DAC crossovers have made me think that I'm not such a hopeless speaker designer after all! Cheers,
Frank
re: Lagato 2....
On the TPA website, is the schematic and users manual version 2?
The Lagato2 kit that I just receved is screened "Version 2.0.0"
But I can not find any reference to the "doubled up" I/V resistors, i.e. the 680R that was mentioned previously in this thread...or any other doubled up resistor. The docs and .xls parts list don't show the reference... I'm a bit confused.... ( and a little lost without the appropriate corresponding documentation... especially getting ready to purchase components for tweaking, let alone just stuffing the board with original parts)
JD
On the TPA website, is the schematic and users manual version 2?
The Lagato2 kit that I just receved is screened "Version 2.0.0"
But I can not find any reference to the "doubled up" I/V resistors, i.e. the 680R that was mentioned previously in this thread...or any other doubled up resistor. The docs and .xls parts list don't show the reference... I'm a bit confused.... ( and a little lost without the appropriate corresponding documentation... especially getting ready to purchase components for tweaking, let alone just stuffing the board with original parts)
JD
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current documentation for the current product... that's all. As that is what I would reference when building (intead of going back and forthing to figure out the differences) I confuse easily and need an exact "paint by the numbers" reference as the baseline.
example.... enclosed in the parts are 681 ohm resistors...... there is no reference to the in the parts list or schematic so I have to clue where they go.......
For me it's difficult to learn how a 2011 Ferrari is put together if I have a 2010 manual.
JD
example.... enclosed in the parts are 681 ohm resistors...... there is no reference to the in the parts list or schematic so I have to clue where they go.......
For me it's difficult to learn how a 2011 Ferrari is put together if I have a 2010 manual.
JD
What kind of reference are you expecting to see?
There should be 4 resistors per side where before there were only two.
And there is also no buffer to omit.
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