Mitäs opariasiantuntija(t) sanoo OPA2134 korvaamisesta LM4562:lla?
Tuolaista moni, itseni mukaanlukien, harrastanut Linkwitz Orion aktiivisuotimessa (plug&play vaihtona). Moni on ollut aivan onnessaan. Itse en oikein tiedä..
Tuolla muutama Linkwitzin (nimim. SL) kommentti asiaan
http://orion.quicksytes.com/viewtopic.php?f=1&t=946
Edit. eikun täällähän se varsinainen pitkä ketju aiheesta oli
http://orion.quicksytes.com/viewtopic.php?f=3&t=303&st=0&sk=t&sd=a&hilit=lm4562
Tuo ketju on rekisteröityneiden alueella joten laitan pari SL kommenttia oparivaihdosta tähän.
"
Please note, the LM4562 has a 56 MHz gain-bandwidth product and therefore its behavior in the ASP has to be carefully tested for spurious very high frequency oscillation and at varying input signal levels. Also its low 100 pF load tolerance could be a concern though I include 196 ohm resistors in the outputs before any cables add capacitance.
The evaluation could be done with a 100 MHz oscilloscope or a spectrum analyzer. I will have a look next year when the ICs are readily available, but maybe someone else can investigate this beforehand and report their findings before people jump to conclusions from possibly flawed listening tests.
"
First of all let me explain the filtering on the ASP which uses inductance, the resistance of a diode and large and small capacitors. The purpose is to become independent of the external power supply filtering. Voltage regulation is not an issue though. But if someone uses a regulated supply, then the large capacitance of my filters can easily make it unstable. That would be perfectly normal, because regulated supplies have a feedback loop and their response is designed with a maximum capacitive load in mind, e.g. <100 uF. No reason to jump on anyone when they make allowance for that.
The LM4562 has potentially higher noise and radio frequency oscillation in the ASP circuit because I did not design it with such wide bandwidth opamps in mind. Several people are investigating this right now. If nothing is found that might degrade circuit performance, then any subjective evaluations are at least not influenced by artifacts.
Frankly, I am skeptical that anything different should be audible, but who knows. Certainly something can be learned from listening tests. Just don’t take them personal, even though they are personal experiences, and others may not go along. Let’s not start another divisive religion over this. And do not wait for my blessing. I will come to my own conclusion in time, but right now I have other priorities.
If what you find adds to your enjoyment of the music, then go for it and thanks for sharing.
I am the type who also wants to understand what is going on.