There was a huge thread on this and the best guess was about 3 min. into Pines of Rome was lifted by someone in Hollywood.
by Bruno:
Review and Measurements of Purifi 1ET400A Amplifier | Audio Science Review (ASR) Forum
Old farts era has definitely ended (me included)
This performed well too:
Review and Measurements of Benchmark HPA4 Headphone Amp/Pre | Audio Science Review (ASR) Forum
Could be. IIRC, as you mention now and then for circuits, its all been done before. In music the problem is much worse, since there are only 12-notes in a scale (in Western music), and fifths are in nearly every chord (relative to the chord tonic). Therefore, brief sequences are reinvented all the time. Sometimes they are borrowed as well. Very hard to be sure which is the case in many instances.
Guitar, for about 50 years now. When I was young learned reading and theory - then forgot most of it. Theory is important, but all the theory in the world won't write a good song. Have done quite a bit of writing.
It's not that simple. I listen to a lot of things on a lot of different levels but also just forget all that and get into the performance as a whole.
Yes, indeed. Last time I looked at the Benchmark website, both units were sold out.
If there is a DAC-4 and it turns out to be a full featured AK4499 design, I think some of the people who claim low level distortion, detail, etc., are all inaudible and can't matter may be surprised when they compare what they are using now to a system comprised of the technology that is becoming available from the likes of Benchmark, and guys like Bruno.
Even Amir seems to be impressed with the sound of the headphone amp.
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Can you describe the new sound, and where in the circuit is the resistor ? I hear you about fine differences making such subjective differences, and I have extracted differences due to cables and ferrite filters and they do correlate with subjective findings.
Dan.
BZZZZT, you did: https://www.diyaudio.com/forums/the...owtorch-preamplifier-ii-9837.html#post5277836
Ain't search engines a bitch?
I did find that post and nope
is not stating that Bill is a "winging pom" but it is saying that he has acted like such description, two very different cases. Bill has chosen to bring this up himself and it is best that you keep out of this discussion, thank you.
Dan.
Really? Putting in a link into that kind of stuff kind of paints you for what you are in my book. You put no disclaimer in there so how precisely is one expected to read that?
The denial of science and reason at every turn . . .
Well I’ll toss it out there bit by bit and see what happens.
Speaker wire.....
I’ve found it does indeed make a difference but not because you need the latest greatest most expensive boo-teek wire.........it’s more about the LCR and matching. Your all gonna say the measureable differences are to small to make a difference but I’ll go to the mat saying it does.
Materials matter also but I never got to compare different wire that had the same LCR measurements so I can’t really say for sure.
In a nutshell the people that find so much difference in high dollar cables is most likely due to finding a good match for their system......a match which could be had for much less $$ with a little experimentation. But hey if you have the money and you just have to have the leopard skin sheathed wire with fossilized amber and quintuple 9 fine terminations then who am I to judge.
Edit.....oh yah (your gonna love this one) I found that disturbing the system in any way such as changing of speaker wire did indeed ‘upset’ the system. It usually took anywhere from 30-90 min to settle.....sometimes a little longer. And it’s not wiping off oxidation......it never really had time.
So we are supposed to believe this on faith? Sorry I still dont believe in your hearing, no matter how many time you tell us its great. Heard that too many times. Its probably your brain that needs settling time.
And a quick question, did you measure the crossover components to make sure they were the value printed on them?
An oft overlooked or dismissed phenomenon.
And keep a Sharpie with you to write the actual value on the part.
Would that comparison be level matched and visual bias controlled or level unmatched and sighted?
I'm impressed with the sound of built-in DAC in $99 disc player. That means it's a valid evaluation, I suppose. BTW, I'm not in audio business so it means my review is not tainted with commercial interest.
The actual value is (slightly) less important than the corresponding component in each crossover are within a close tolerance of each other (if there's going to be a dip in frequency response, it's best to have the same dip in both speakers). To do this, add an appropriate value cap in parallel with the smaller value to make them as close as practical (or buy extras and sort as I describe below). Some may claim that this also needs to be the same brand or "quality" as the main cap, but just getting the component values to match within a tight spec is a good start.
I like to put a simple serial number on components (#1, #2, #3, #4, ...) and keep a record of the measured values in a spreadsheet. If you've got (for example) qty. ten of a component, a sort of both columns brings the best-matched pairs into adjacent rows. Make a third column of adjacent differences and look for the smallest one(s).
It is a circuit like the one attached except ground the loose end of the 10k resistor and signal input is put into the non-inverting node. I have different resistor values.
The resistor I had to change is the one labled 2M2 (221k in my circuit though). My version has 40db of gain so everything is magnified. At that kind of gain the 2M2 position plays a much bigger part in the quality of the high frequencies than one would think. This is in spite the corner frequency being at about 200hz!
I had initially used a pretty nice thin film SMD resistor and that is what sounded bright and scooped. Could have been useful for a mic preamp or some such but for LP playback it wasn't my cup of tea.
So went back to what I usually use in that position; a big, over rated Dale RN65.
Midrange came back
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