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post #211 of 274 Old 06-30-2019, 05:44 PM
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Originally Posted by drh3b View Post
Well, since you didn't quote a person, you just asked about equipment, not sure who you are talking about. If you're still talking about imagic, he has a gig reviewing audio/video equipment here, so he's heard more than you can dream of. He's also gone to high end shows in the past. He does have certain equipment that is his, plus a whole bunch floating through. If you really want to know what he has, read his reviews, he doesn't hide it.
I can attest to Mark's prowess with subjective listening too. We both stood around face to face outside a certain room at AXPONA 2017 and had just about the same conclusion regarding what we had just subjectively heard. And, btw, we were not in the room at the same time. I was in there and then up to room 1247 while Mark was in the subject room. I ran into him when I got back down from the 12th floor when he was exiting the room. If you read our show recaps, we said pretty much the same. I did mine day by day so mine was up that night, before I read his. He heard the same issues I did and they were fairly serious issues for an $80k pair of speakers. I know he does measurements, but he also 'hears' pretty well too.
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post #212 of 274 Old 06-30-2019, 05:45 PM
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I was quoting from post #197 , where did you get the 3 rooms over?
Come on, dude.

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post #213 of 274 Old 06-30-2019, 05:47 PM
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I just want to know the people here joking about golden ear and all what do they have. It's all fun and game, like can tell from the other room.


I am confused, is this supposed to be offensive to ask what people have? Particular people that have strong opinion, maybe we can learn something about paying less for mor.
"about golden ear"

Hopefully, you meant 'golden ears' as in plural or we'll be spending out listening moments listening to Duke Ellington - Masterpieces, Circa 1950.

Btw, fantastic album so if you ever have a little Mood Indigo, here's your album.

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post #214 of 274 Old 06-30-2019, 05:54 PM
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You can't tell how good stuff is from at least 3 rooms over?!? How can I take you seriously?

I believe you can be aware of tonality just as well or maybe better from another room. Or in my case it's sort of an 'L' shape. Living room and speakers facing this direction, and the end of a long hall, toward the front door, then my office is on the right. I'm just as aware of tonal coloration or lack thereof in this room.
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post #215 of 274 Old 06-30-2019, 06:23 PM
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I read a few posts and it looks like this thread went down south really quickly (into measurements vs testings and 'audiophile' snake oil gibberish), but I don't even want to comment on that.


What I find really amusing is the statement that DBT testing would be somehow short-term memory related. It's the same thing as saying that I, as a mixing engineer in the studio, am not able to tell what guitar amp would fit the mix/genre/guitar/band better, because of short-term memory. It doesn't even make any sense, how can someone even come up with this. It's not like you're listening to speaker A, then wait 3 hours while doing nothing, then listening to speaker B. The differences are immediately obvious, so this whole argument is based on wrong facts.


One more thing:
is one of my reference tracks for system comparison (well, not YT quality). Enjoy!

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post #216 of 274 Old 06-30-2019, 06:26 PM
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Originally Posted by peniku8 View Post
I read a few posts and it looks like this thread went down south really quickly (into measurements vs testings and 'audiphile' snake oil gibberish), but I don't even want to comment on that.


What I find really amusing is the statement that DBT testing would be somehow short-term memory related. It's the same thing as saying that I, as a mixing engineer in the studio, am not able to tell what guitar amp would fit the mix/genre/guitar/band better, because of short-term memory. It doesn't even make any sense, how can someone even come up with this. It's not like you're listening to speaker A, then wait 3 hours while doing nothing, then listening to speaker B. The differences are immediately obvious, so this whole argument is based on wrong facts.


One more thing: here is one of my reference tracks for system comparison (well, not YT quality). Enjoy!

Audipile? Yeah, I could agree with that
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post #217 of 274 Old 06-30-2019, 06:30 PM
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Originally Posted by Scotth3886 View Post
Audipile? Yeah, I could agree with that

That's something you might find on the scrapyard I guess

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post #218 of 274 Old 06-30-2019, 06:42 PM
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Originally Posted by peniku8 View Post
I read a few posts and it looks like this thread went down south really quickly (into measurements vs testings and 'audiophile' snake oil gibberish), but I don't even want to comment on that.


What I find really amusing is the statement that DBT testing would be somehow short-term memory related. It's the same thing as saying that I, as a mixing engineer in the studio, am not able to tell what guitar amp would fit the mix/genre/guitar/band better, because of short-term memory. It doesn't even make any sense, how can someone even come up with this. It's not like you're listening to speaker A, then wait 3 hours while doing nothing, then listening to speaker B. The differences are immediately obvious, so this whole argument is based on wrong facts.


One more thing: here is one of my reference tracks for system comparison (well, not YT quality). Enjoy!
One of my two favorite symphonies. Probably going to get this, I only have at least five versions already.

Yeah, if short term memory isn't useful, how did we get the hundreds of thousands of recordings we have, some of which sound really good? They didn't just produce themselves.

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post #219 of 274 Old 06-30-2019, 07:10 PM
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Come on, dude.
Come on what?

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post #220 of 274 Old 06-30-2019, 07:15 PM
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One of my two favorite symphonies. Probably going to get this, I only have at least five versions already.

Listening to it every now and then, sometimes in the car and also seen it as live performance. Every single time is a trip though goose bumps and the occasional tear (one of those "single tear pesons"). I'm an orchestra percussionist myself and man.. what I'd give to perform this on the timpany.. sadly my current orchestra is a brass orchestra
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post #221 of 274 Old 06-30-2019, 07:18 PM
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Originally Posted by peniku8 View Post
I read a few posts and it looks like this thread went down south really quickly (into measurements vs testings and 'audiophile' snake oil gibberish), but I don't even want to comment on that.


What I find really amusing is the statement that DBT testing would be somehow short-term memory related. It's the same thing as saying that I, as a mixing engineer in the studio, am not able to tell what guitar amp would fit the mix/genre/guitar/band better, because of short-term memory. It doesn't even make any sense, how can someone even come up with this. It's not like you're listening to speaker A, then wait 3 hours while doing nothing, then listening to speaker B. The differences are immediately obvious, so this whole argument is based on wrong facts.


One more thing: here is one of my reference tracks for system comparison (well, not YT quality). Enjoy!
I guess they assume everyone has really bad ears. I don't consider myself have golden ears, but I can sure remember a lot of what I heard at least for a few hours. I know one person that play guitar, I had a few distortion pedals I design which is a different variation only, he can point out the one he heard last time a month ago. Those pedals are NOT of different design, just change the clipping diode. The difference is small enough, but he could just point out the one he heard before.

I know a lot of people have short memory, or they really cannot tell the difference, but some people can. The worst part is those that cannot insist on people that can are hearing things.


I had been a musician performing in concerts for quite a while long time ago, I consider myself have quite good ears. I sure know a lot of people that have really bad ears from teaching guitar. So I am not surprised.
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post #222 of 274 Old 06-30-2019, 07:30 PM
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I know a lot of people have short memory, or they really cannot tell the difference, but some people can. The worst part is those that cannot insist on people that can are hearing things.
Does it even matter that some others don't believe you? What's the end game in getting the skeptics to believe you?

I would have an easier time convincing people of Simulation Theory than my experience of hearing an actual difference between multiple DACs.
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post #223 of 274 Old 06-30-2019, 08:10 PM
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Does it even matter that some others don't believe you? What's the end game in getting the skeptics to believe you?

I would have an easier time convincing people of Simulation Theory than my experience of hearing an actual difference between multiple DACs.

I do both theory and listening and testing. I have people come over to do blind testing also as I design amps. People consistently being able to tell the difference.

Sometimes, I think those who cannot tell the difference are lucky, they don't have to be picky, just buy anything and they'll be happy, just don't tell people that can hear the difference that it's all in their heads.


Good ears is a gift, most people don't have it. Most people don't have to be sound engineer or be a musician that have to have good ears.
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post #224 of 274 Old 06-30-2019, 08:21 PM
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I do both theory and listening and testing. I have people come over to do blind testing also as I design amps. People consistently being able to tell the difference.

Sometimes, I think those who cannot tell the difference are lucky, they don't have to be picky, just buy anything and they'll be happy, just don't tell people that can hear the difference that it's all in their heads.


Good ears is a gift, most people don't have it. Most people don't have to be sound engineer or be a musician that have to have good ears.
You know what's also a gift? Not giving a damn that some people think you are delusional. No need to get so defensive over something this trivial.

For the record, I have convinced myself that some DACs do sound quite different from each other. So what do I do with this information other than just enjoy my system?
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post #225 of 274 Old 06-30-2019, 08:46 PM
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You know what's also a gift? Not giving a damn that some people think you are delusional. No need to get so defensive over something this trivial.

For the record, I have convinced myself that some DACs do sound quite different from each other. So what do I do with this information other than just enjoy my system?

I am not familiar with sound of DACs, I can only say power amps with different topologies sound different even though all of their THD measurement are below 0.005% at 50W and 20 to 20KHz. When I did blind test, people can pick it out in one or two minutes consistently.



I know in preamps, the opamps used make a difference in sound, in general opamps with JFET transistor input sound livelier. All the opamps are 0.0005% or lower THD, but they sound different.

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post #226 of 274 Old 07-01-2019, 06:30 AM
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I know in preamps, the opamps used make a difference in sound, in general opamps with JFET transistor input sound livelier. All the opamps are 0.0005% or lower THD, but they sound different.
I was into the PC sound card craze that was most prominent during the early and mid-2000s, when the go-to solution to achieve a different sound was switching out opamps. Auzentech made some of the best sound cards, but they unfortunately dissolved as high quality USB DACs became much cheaper and more reliable.
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post #227 of 274 Old 07-01-2019, 09:15 AM
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I was into the PC sound card craze that was most prominent during the early and mid-2000s, when the go-to solution to achieve a different sound was switching out opamps. Auzentech made some of the best sound cards, but they unfortunately dissolved as high quality USB DACs became much cheaper and more reliable.
I have been working on power amps for like 3 years, my experience is there is a disconnect between measurement, spec etal. from the sound you listen to it. I cannot explain with science. Me and my friends did a lot of switching opamps in our preamps, they have distinguish difference just by switching. I designed 4 amps, the first 3 has the exact same power supplies, EXACTLY the same output stage. The only difference is at the front end. 1st one is the basic entry level design. 2nd is my own design that is very different from all the commercially available, the 3rd is more the Krell type with more. All of them are below 0.005% THD into 4ohm. You would think they all should sound the same..............NOT!!! people can pick out each of them consistently and fast in the blind test.

Then the 4th amp which I added error correction in the output stage, but the frontend is exactly like the 3rd amp. THD is down to 0.002% from 20 to 20KHz into 4ohm @50W. I spent 7 months working on this. I ran the blind test. WE COULDN'T hear much difference from the 3rd!!!! They both have the same frontend.


How the hack can you explain that? That's so disheartening!!!

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post #228 of 274 Old 07-03-2019, 10:46 AM
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How is this a problem? Certain people refuse to test equipment, but instead look at price tags as an indicator of quality. I've brought this up before. If Yamaha were to take a stock soundbar from Best Buy, paint it gold with Rustoleum and upcharge 5x the original MSRP, that's all it would take to make it "high end".

I believe it was Krell that replaced the face plate of an Oppo TOL blueray player with one of their own and charged 10x the asking price of the original Oppo... Lots of high end engineering there I'm sure to ask for such an exorbitant price hike.
I wonder how many short cuts are taken by the high-end manufacturers. Expensive doesnt always equate to being good. The only high end manufacturer I would consider is Bryston as they stand behind their products with one of the best warranties out there.
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post #229 of 274 Old 07-03-2019, 12:50 PM
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I have to agree about Krell. I studied their KSA power amps, The design are very crude, missing a lot of stuffs. My conclusion is they just brute force with big heatsink, run in class A all the way to cover up the short coming. But still there is a lot to be said about being pure class A.


I don't know the history of all amp design, I think Krell might be the first one to come up with the what we called Complementary IPS front end. My guess is other people copy the design. Again, I don't know the history. I heard the designer that design the KSA also design Aragon and Acurus. They all have the same type of design. Bryston also use the Complementary IPS.


I designed and built a few amps with different frontend, still the one with the Complementary IPS consistently sound the best. As I said many times, spec and THD don't tell you anything on the sound and different frontend do give different sound. If it is true that Krell was the original one that came up with it, then I won't put them down so much. But I don't know, I am just guessing.


From studying the circuits, I like the Adcom GFA-565 the most. It is Complementary IPS, but add a whole lot more then Krell.


Good amps are going to be more expensive, there's no other ways about it, it's about the cost of the big chassis with big heat sink, the cost of the capacitors, the transformers and lastly, the transistors. BUT just because it's expensive doesn't mean anything that the sound is good. I can tell you, each of my amp cost me $900 just for the parts only, I cannot make it any cheaper. It's only a small amp of [email protected], [email protected] and [email protected] I made them this small because any higher power, I have to use much bigger chassis not only cost more, it's a lot heavier also. They sell those Krell CLONE big chassis on ebay for DIY, they are over $500 each. So you can put it in perspective.
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post #230 of 274 Old 07-03-2019, 01:28 PM
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Originally Posted by 3db View Post
I believe it was Krell that replaced the face plate of an Oppo TOL blueray player with one of their own and charged 10x the asking price of the original Oppo... Lots of high end engineering there I'm sure to ask for such an exorbitant price hike.
I wonder how many short cuts are taken by the high-end manufacturers. Expensive doesnt always equate to being good. The only high end manufacturer I would consider is Bryston as they stand behind their products with one of the best warranties out there.
I don't think you'll get much argument about the price aspect. Only a complete fool would think that price is a guaranteed indicator of quality.

Even big manufacturers such as Denon and Sony historically sold some of their limited quantity high-end equipment for seemingly exorbitant amounts of money, but they of course usually do their own design and R&D for such gear. Speaking of Denon, whatever happened to Jeff Talmadge?
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post #231 of 274 Old 07-03-2019, 02:43 PM
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Most of the audible differences I have heard/measured are more related to output impedance than distortion, especially at low levels. Hiss can be an issue if you've too much amp (or too low SNR) for the speakers, e.g. high-power amps and horns six feet away are usually a poor match.

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post #232 of 274 Old 07-03-2019, 03:12 PM
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Originally Posted by 3db View Post
I believe it was Krell that replaced the face plate of an Oppo TOL blueray player with one of their own and charged 10x the asking price of the original Oppo... Lots of high end engineering there I'm sure to ask for such an exorbitant price hike.
Close. It was Lexicon: https://www.audioholics.com/blu-ray-...ray-oppo-clone.

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I wonder how many short cuts are taken by the high-end manufacturers. Expensive doesnt always equate to being good. The only high end manufacturer I would consider is Bryston as they stand behind their products with one of the best warranties out there.
Simaudio Moon also appropriated the entire digital section of a $1200 Denon AVR (without permission) for a pre/pro they charged $18000 for. [https://www.audioholics.com/av-pream...cp-8-processor.] Tip of the iceberg.
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post #233 of 274 Old 07-03-2019, 04:26 PM
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I think I mentioned this in another comment when you brought up this topic before, I think there must be a flaw in the testing methodology, that's what makes the most sense here. I don't know if I'm right or wrong, I'm just making an educated guess.

I appreciate that you design amps, that's a cool skill, but speaker cable nonsense I just really can't... Sorry. I'm not convinced. And that's the thing, a proper blind test would ideally be conducted by a qualified third party. With a publishable testing protocol. Just sayin'. And yes that basically restricts it to companies that can afford to do that.
He mentioned that he "doesn't say anything" during the test, which leads me to believe he does them single blind, not double blind.
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post #234 of 274 Old 07-03-2019, 04:59 PM
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Originally Posted by GIEGAR View Post
Close. It was Lexicon: https://www.audioholics.com/blu-ray-...ray-oppo-clone.


Simaudio Moon also appropriated the entire digital section of a $1200 Denon AVR (without permission) for a pre/pro they charged $18000 for. [https://www.audioholics.com/av-pream...cp-8-processor.] Tip of the iceberg.
That is freakin' hilarious. At least they copied engineers who actually knew what they were doing.
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post #235 of 274 Old 07-03-2019, 05:11 PM
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Most of the audible differences I have heard/measured are more related to output impedance than distortion, especially at low levels. Hiss can be an issue if you've too much amp (or too low SNR) for the speakers, e.g. high-power amps and horns six feet away are usually a poor match.
I can tell you from a lot of testing with people, All 3 of my amps have the exact same output stage OPS, in fact, when I layout pcb, I use the layout of the last amp and just modify the frontend circuit, I did not even touch the OPS side of it and fab the pcb. Everyone is the same 9 pairs output transistors with 100mA per pair, 3EF stage. The power supply is exactly the same, they all sounded different and people have no problem distinguish the 3 within a minute or so. All have THD below 0.005%@20KHz at over 50W, and 0.0015%@1KHz.You would think at this low THD, they should sound the same, they are NOT. No spec can predict this.

On my 4th amp I spent over 7 months design, text and built. I put in the error correction into the OPS to further up the damping factor and reduce the crossover distortion. I use the same frontend as the 3rd amp unchanged. We could hardly hear the difference in testing!!! It's so disheartening!!!

You would think OPS govern the sound, I don't see that. You would think the front end is just like the front end of the opamp with differential pairs and they should not matter. It matters!!! I did not believe this, but it's proven from real life testing with people. There is a lot we don't understand.....at least I don't understand. I don't see direct connection between scientific measurement and sound.


That's why it's laughable when people say amps all sound the same as long as they are not clipped. Here I am, working over 3 years, hours a day designing, measuring, testing and listening like as if I am working part time in my real career, NONE of my amps including the PA-7 and Acurus sounds the same. They are all WAY below clipping level. I really question either they don't have the ears or just believe so firmly that it doesn't make a difference that they don't even listen.

Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.

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post #236 of 274 Old 07-03-2019, 05:31 PM
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He mentioned that he "doesn't say anything" during the test, which leads me to believe he does them single blind, not double blind.

But my amps all look the same, it's not one is Krell, one is Yamaha. Look at the picture, all are made identical in every respect. You can't even tell the difference if you look inside. Only I know which one is which.
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Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
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post #237 of 274 Old 07-03-2019, 05:54 PM
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Originally Posted by alan0354 View Post
But my amps all look the same, it's not one is Krell, one is Yamaha. Look at the picture, all are made identical in every respect. You can't even tell the difference if you look inside. Only I know which one is which.
Sorry, what you're describing is not the true double blind methodology.
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post #238 of 274 Old 07-03-2019, 05:55 PM
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But my amps all look the same, it's not one is Krell, one is Yamaha. Look at the picture, all are made identical in every respect. You can't even tell the difference if you look inside. Only I know which one is which.
Sorry, what you're describing is not the true double blind methodology. You're not supposed to know either.
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post #239 of 274 Old 07-03-2019, 05:59 PM
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Sorry, what you're describing is not the true double blind methodology. You're not supposed to know either.
I am not the one to judge, I know how they sound. I want to know what people think.


Don't put too much weight on DBT, people just read articles and think it's all true. I do this all the time, testing, listening, designing and building. You have to spend time with it for a few days to tell.
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Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
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post #240 of 274 Old 07-03-2019, 06:34 PM
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I am not the one to judge, I know how they sound. I want to know what people think.


Don't put too much weight on DBT, people just read articles and think it's all true. I do this all the time, testing, listening, designing and building. You have to spend time with it for a few days to tell.
I put weight on unbiased evaluations, not biased ones.
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