The soldered stack presents a wonderful opportunity to surreptitiously introduce a placebo into the listening tests.
100 ohm resistors on pins 1 and 7 and a .1 microfarad cap across + and - pins 4 & 8.
With caps and resistors this is running cool. with no resistors the outputs will have a battle royal.
He even says that in a previous video. It works and sounds great, not forcing anyone to try it. Not sure where you are going with this.
Yes, master and slave op amps will run cool. I think you've totally missed the point, mine run cool, the heat sink is just a safety to avoid a chimney effect and they sound great.
He will tell you **** smells wonderful and is tasty as a michelin restaurant dish, because he sells those.... Also, not his invention...
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Those paralleled opamps from company Virtual HiFi are running very hot, they know what to charge for their products though. :)
Below link to my earlier post there's an IR picture attached showing how hot those are running with the heatsinks on.
ps. the whole post is not visible, so go to the actual post to view full content.
Well...so far zero heat issues and sounds great. He is smart to have heatsinks for enclosed cases. Yup, saw all his info and even his warnings. After I post actual samples, if people hate it fine, in the meantime I will simply ignore anymore folks that don't actually want a discussion.
Is there anything you would like to discuss?
Is there anything you would like to discuss?
Only thing i could think of is higher current output
Yes, now we are talking. This is why Greg from virtual HiFi also pursued this. I did a vid on how a Sparkos op amp swap worked, and it worked extremely well. Not the same thing at all, but for the folks that can't hear the difference between op amps, I recommend a critical listening class or a hearing aid. Not directed at you, just the folks that judge without listening or have zero ability to discern differences.
@jazzboy sure keep on with your project, could you perhaps measure the voltage over those 100R's output resistors at standby, ie no input signal, that would show how much DC offsets there is.
As for Virtual HiFi I have no idea what they are doing to make the opamps draw so much current, but guessing they loaded the output so the opamps run in Class A.
As for Virtual HiFi I have no idea what they are doing to make the opamps draw so much current, but guessing they loaded the output so the opamps run in Class A.
FWIW in the Yamaha TX950 they paralleled the two halves of an NJM 2068 dual opamp. They did it to lower the noise. I suspennt there are other chips with low enough offset and close enugh match to get away with this. They would most likely be recent chips on new processes where everything is a much closer match.
Will do next swap. I am using the same value resistors as in his photos and from reading, the .1 micro arrad was chosen. So not sure the heat. But!!!!! I am using the setup in a phono pre.
The resistors are used as buffers between the outputs of the op amps. Tons of info on doing that.