I always go long...
Trying to read everything to get back up to speed. Even spent time in reading in "The Great Speaker Cable Debate."
What I have found most interesting is the D amps and MOSFET for their efficiency and power. Having read the Lepai mods, i.e. replacing op amp with something better got me here.
Meanwhile back at the ranch I still be thinking of DIY projects and ones I have done in the past. For instance I have built R/2R resistor ladders for D/A convertors on both MS DOS and Atari platforms. While I am sweating the details of my next project, I would like to do something strong but lame: Something like an 8 pin Tiny AVR using PWM to drive a power MOSFET in D mode, I decides to take a look back at my old friend R/2R as it relates to AVRs.
In R&D the common wag is "One experiment is worth 1000 theories."
R/2R-network as DAC for an AVR
Those invested in this discussion may find the substitution of 741 for the 3140 to be interesting. First they used kind of a cheap solution to get things in range i.e. just used 7 bits instead of 8. It probably would have been better to just use a divider on the op amp input. Point being even using only 7 bits things looked like crap with the 741 because of its construction<?> limiting its voltage response range.
Not to try and drift the thread but I was suprised at what the 7 bit DAC sin wave looked so good. I specifically mean I know the R/2R is producing a step approximation but the curve is smooth as a baby's behind. There is a 1/128 or ~1% error in there but your eyes can not see it on the scope but your ears could possibly hear it!
Rick
Trying to read everything to get back up to speed. Even spent time in reading in "The Great Speaker Cable Debate."
What I have found most interesting is the D amps and MOSFET for their efficiency and power. Having read the Lepai mods, i.e. replacing op amp with something better got me here.
Meanwhile back at the ranch I still be thinking of DIY projects and ones I have done in the past. For instance I have built R/2R resistor ladders for D/A convertors on both MS DOS and Atari platforms. While I am sweating the details of my next project, I would like to do something strong but lame: Something like an 8 pin Tiny AVR using PWM to drive a power MOSFET in D mode, I decides to take a look back at my old friend R/2R as it relates to AVRs.
In R&D the common wag is "One experiment is worth 1000 theories."
R/2R-network as DAC for an AVR
Those invested in this discussion may find the substitution of 741 for the 3140 to be interesting. First they used kind of a cheap solution to get things in range i.e. just used 7 bits instead of 8. It probably would have been better to just use a divider on the op amp input. Point being even using only 7 bits things looked like crap with the 741 because of its construction<?> limiting its voltage response range.
Not to try and drift the thread but I was suprised at what the 7 bit DAC sin wave looked so good. I specifically mean I know the R/2R is producing a step approximation but the curve is smooth as a baby's behind. There is a 1/128 or ~1% error in there but your eyes can not see it on the scope but your ears could possibly hear it!
Rick
for clearing things up sake's, as english is not my native tongue...is bulldada the same as mumbo jumbo
Audio reviewers of this ilk used to be called guessers (GESR's) - Golden-Eared Subjective Reviewers...
maybe tomorrow I'll swap the burson for two 1028ACN8...just as a reality check, I find those "IC's sound better than discrete" statements dubious to say the least
1124 + 1028 doesn't look that complementary numerically... but if you say you're colorblind, why not try
Anyway, I have no need to establish that either my favorite chips sound better than 'discrete' or the opposite. The LT1028 and others simply sound excellent, that's enough for me. Think of it, I remember how much I liked the LME49720HA as well. It might be worth for me to try the LM4562HA too (no, it mustn't sound identical).
I think it's really absurd to conceive an "audio review" that isn't subjective.
For me the real problem is another. You would presume that those involved in such quality judgments would be endowed with a good taste in music - thus with ears & mind trained to beauty enough to discern. Unfortunately, no, most of the time, audio reviewers have such a discomforting taste in choosing the music to listen with their stuff... And by correspondence...
So, in the end, I only completely trust the subjective reviews of those who have musical tastes compatible with, or not too distant from mine. As a music lover above all, I think it's the only criterion to follow...
Funnily enough, those who do believe that any quality judgment can ever be objective, will tend to forget about musical taste at all... kind of like humanity wasn't composed of billions of different individuals with each a different perception of things
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And still to go back to my original point... all you guys are saying about the wonderful sound of these devices, how transparent etc, yet those very properties could surely be said to apply to the 5532/4 LM833 etc etc that the music was mixed on.
So are the various combinations of device leading to a "coloured" sound that you happen to like.
So are the various combinations of device leading to a "coloured" sound that you happen to like.
Hey, you guessed right... I have a dermatitis caused by stress/tension in my righ ear, which from time to time tends to partially close my ear canal... Time for a visit (booked for tomorrow morning).Perhaps the golden ear has tarnished somewhat
Yet, the stock TI5534 of one of my DACs were pretty much intolerable for my ears due to that shrill upper midrange, and the closed-in sound. I would have started with a pair of LT1357 as stock...
At any rate, let's make it clear that nothing is perfect... not even my favorites LT1028, LME49720HA, and the others mentioned in the first post. They all have their little flaws I could always put my finger on... but... this is life...
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You would be surprised at just what the ear can detect.
Take an amp/speaker and say a pure low level sine at 2 to 4 khz. If you reduce the bias on a Class AB amp the "harshness" appears in the sound before the crossover spike become detectable on a 'scope.
I have a very good function generator with a "low" THD yet the sine on that sounds rough and harsh compared to a Wein oscillator. Looks perfect on the 'scope though.
Hey, you guessed right... I have a dermatitis caused by stress/tension in my righ ear, which from time to time tends to partially close my ear canal... Time for a visit (booked for tomorrow morning).
Most will have seen them but for those that haven't,
Amplifier Institute Failures
Regarding the potential new DAC to buy...
I like this, in case I couldn't save up enough for the NG94...
HA INFO - HA INFO NG98 - Amplificateur casque + DAC USB SPDIF CS4398
The nice thing is that it could make a good headphone amp for my (currently unused) Senn. HD650, besides a good DAC. True, the line out is via mini-jack, but I do have a few practically new mini-RCA cables I'd like to put into service... Chord iChord, Kimber Cable GQ-Mini, etc.
For the line out buffer, it has a dual opamp... I guess I'd put in one of my already made LT1028ACN8 browndogs, or maybe I'd buy a pair of ADA4627-1...
For the rest, parts quality looks high enough not to demand any other tweaking... only those two Nichicon bipolar caps (predictably in the line out signal path) could like a small polypropylene bypass.
I like this, in case I couldn't save up enough for the NG94...
HA INFO - HA INFO NG98 - Amplificateur casque + DAC USB SPDIF CS4398
The nice thing is that it could make a good headphone amp for my (currently unused) Senn. HD650, besides a good DAC. True, the line out is via mini-jack, but I do have a few practically new mini-RCA cables I'd like to put into service... Chord iChord, Kimber Cable GQ-Mini, etc.
For the line out buffer, it has a dual opamp... I guess I'd put in one of my already made LT1028ACN8 browndogs, or maybe I'd buy a pair of ADA4627-1...
For the rest, parts quality looks high enough not to demand any other tweaking... only those two Nichicon bipolar caps (predictably in the line out signal path) could like a small polypropylene bypass.
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BTW, I'm listening to the EELS' "Hombre Lobo", and being impressed with the bass quality the LT1028 manages...
I remember the bass lines of this CD as being a bit messy and invasive with the LT1363, and not this fast and well-articulated even with the LME49720HA...
This CD really benefits by the recent LT1028 treatment of my DAC.
I remember the bass lines of this CD as being a bit messy and invasive with the LT1363, and not this fast and well-articulated even with the LME49720HA...
This CD really benefits by the recent LT1028 treatment of my DAC.
Thank you very much; congratulations on your superior discernment, too.
Not meaning to offend anyone, but... do you really feel that I've been in competition with leeperry?
I told you we'd better keep it in PM...these very smart ppl can't hear a difference between all these op-amps(wooden ears maybe?)...they have to be the smartests ones amongst us, right?Not meaning to offend anyone, but... do you really feel that I've been in competition with leeperry?
they don't send it as sample, and it's pretty pricey.