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PostPosted: Fri Jul 13, 2018 7:17 pm 
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Joined: Thu Jul 05, 2018 4:57 pm
Posts: 245
Location: Homestead, PA, US
Nowadays with quality audio salons getting further apart geographically, we can't always audition what we are interested in. I always enjoyed Sherlock Holmes stories, where a potential client would enter his office & using his deductive skills acquired from long experience, he could deduce all kinds of things within the first 20 seconds of first time seeing them. He'd look at their hands,perhaps their weather beaten face would give a clue as to his occupation, he could tellif thet were right or left handed by looking at the loops on their shoe laces etc. What about an inside picture of an amp, or preamp or CD player?
I recently joined and have not bought on this site yet, but on ebay, often the seller will show several pics of how the component looks inside.
The first thing I look at is the size of the transformer(s). If you see an amp with a big in size transformer, you can make one good inference; that might never be wrong, "the musical instruments will sound big in size." I have never heard an amplifier with a big transformer that didn't' sound "big". It seems to always come with the territory. Of course the opposite can also be inferred, if it looks like the amp or CD player has a small transformer, I wouldn't' expect life size images.The sound can still be "open", but the size of the instruments themselves will be on the small side in all probability, as opposed to, if the said component had a bigger transformer.
Transformers in CD players, tape decks etc. will generally be much smaller than the ones in amps. I have actually seen them as small as a quarter in diameter. I have never heard anything sound big & beefy with such a small transformer. The old saying that you can't tell a book by its cover is true, but at least one thing you can make a good inference on by simply looking inside a component. Beefier transformers also almost always sound faster and more full bodied than smaller ones. There may be a possible exception or two out there, but I have gone through enough equipment to know its one grand Sherlockian inference you can make with just a cursory visual inspection. Since the transformer is likely to be the most expensive component in an amp, an oversize beefy looking one is usually an indication that the manufacturer didn't skimp on parts quality.Experienced hobbyists can also take one look at the color & look of the capacitors and deduce if they are Nichnon, Black Gate etc. Big in size main capacitors are also a real good sign. These amps always or almost always sound more powerful than their wattage rating.
An amplifiers inside showing elaborate metal shielding tells you that the manufacturer did some experimenting with placement of components within the amp, in an effort to maximize performance by considering the negative influences that stray magnetic fields can have on the sound. Also on back, the quality of the speaker connectors can be a telltale sign of just how much care the manufacturer might have gone to.
These are solid things to go on, but you can't quite be a Sherlock Holmes, by just looking. Listening is the smartest thing if you can, with a CD/LP you really know extremely well. Its incredulous how many people will walk into a store and buy equipment after being impressed with a CD they are not familiar with. How do they know if its the equipment or the CD that's the reason for their being impresseed ? Have any of you ever done this and what CD or LP was it that caused you to get that "get your checkbook out feeling"?


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PostPosted: Mon Aug 06, 2018 11:44 pm 
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Joined: Sat Jul 26, 2014 3:33 pm
Posts: 2
Location: Los Angeles, CA, US
I only purchase components that I can upgrade and steer clear of anything that uses SMD circuitry. It's a real pet peeve to see expensive high-end components using PCBs loaded with tiny everything.

Take a look at this link - http://www.tonepublications.com/spotlight/visiting-light-harmonic/
The Light Harmonic DaVinci DAC costs $20,000. The link shows one of the DaVinci's output stages. Of all of the components in that output stage, there's only one pair of normal sized films caps which
are very basic MultiCap PPFXS. At $20k, this DAC should have way better components.

Compare that to something like this: http://sw1xad.co.uk/product/sw1x-dac-i-special/
I much prefer the $2,700 SW1X DAC over the $20k DaVinci.
Quote:
Master clock is based on low noise EC88 triode tube powered by a separate transformer and is output transformer de-coupled from the rest of the circuit

Quote:
Power supply of valve master clock is valve rectified

WOW

High quality PCBs draw my attention because it makes modding very easy. Conrad Johnson and Rogue Audio have excellent made in USA circuit boards. Ask me how I know. :D

The Audio Mirror Tubadour Dac that is currently listed in the mart is a good example of something that I would like to "Frankenstein". It appears that I can get under the PCBs by unscrewing a few screws. Even if I can't, I'll pull the caps or resistors off the top, use small tungsten carbide drill bits to open the eyelets, and install (solder) the new component. There might be ample space on both sides on the center/sideways PCB to replace the 'lytics with film caps such as Mundorf M-Tube caps or ClarityCap TC type. Maybe I can bypass those new film caps from the otherside of the PCB with .47uf V-Cap Copper/Teflon caps. Will this mod make a difference? Will it sound good? How about the internal wires? How will the DAC sound using 26 awg Duelund copper wire? There are too many questions but only one way to find out.

You can't forget about the most important parts to replace and experiment with: the tubes and the output coupling caps. Copper foil capacitors usually sound great in the output position.


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PostPosted: Tue Aug 07, 2018 7:45 am 
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Joined: Thu Jul 05, 2018 4:57 pm
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Location: Homestead, PA, US
When amplifier designers are asked what is the one thing that holds back an amplifiers sound, they often say "its the transformers." Some companies like Audio Note address this by building amps where the transformers are hand wound with pounds of pure Italian silver wiring. There was a French company Sans Pareil (spelling?) which in the 1990's came out with really advanced transformerless amplifiers which could drive normal impedences.The few reviews they got were fabulous. The David Berning company also dabbled in transformerless amps. Futterman and Moscode tried their hand many decades ago along with Sony. Sony's transformerless amps I read could only be used with Sonys special speakers which it said were around 200 ohms. As you know one of the main things transformers do is bring down the electrical impedence driving capability of amps to single digit ohms.


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PostPosted: Wed Aug 08, 2018 7:02 am 
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Joined: Mon Jul 30, 2018 8:11 pm
Posts: 2
Location: Orange County, CA, US
One perspective that can be obtained when "judging components by mere visual inspection" is the pride of ownership of the seller, (or previous sellers if the current seller is not the original owner). By pride of ownership I mean how well the component was taken care of. I'm sometimes surprised when sellers rate a component a 9 or a 10 and, based on the photos, there may be smudges, imperfections, dust etc. So, a general conclusion of the condition of a component can be made based upon the exterior inspection.

In terms of interior inspection I agree with the points already made. But I would also add that I think that viewing the size, type, etc. of the power supply unit would also be useful.


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PostPosted: Wed Aug 08, 2018 2:59 pm 
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Joined: Sun Dec 06, 2015 9:38 pm
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Location: Bellbrook, OH, US
Certain circuits just look cleaner and more elegantly designed. Dual mono type construction, shorter paths, Etc. I must be a real nerd cause I think they should all have plexiglass tops so the works are observable. Lol.


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PostPosted: Wed Aug 08, 2018 5:23 pm 
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Joined: Thu Jul 05, 2018 4:57 pm
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Location: Homestead, PA, US
I play all my equipment with the top cover off. Amps, tape decks, you name it. Like the dust cover on a turntable it rattles. Playing equip. with tops off, usually results in a more natural sound and gains in many areas. I don't worry about dust, except for my turntable, whose dustcover I do replace after the session is over. You owe it to yourself to hear your equipment with the tops off. Some people spray the inside of their metal tops with a liquid rubber and screw it back on, after its made more inert and less prone to rattle.
If you have a rubber mat on your turntable. You owe it to yourself to replace it with something more advanced. Rubber is not the best material under vinyl.


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PostPosted: Wed Aug 08, 2018 5:38 pm 
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Joined: Thu Jul 05, 2018 4:57 pm
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Location: Homestead, PA, US
Re: playing with tops off. Beware with CD players; stray laser light will come out (bad for your eyes), also watch with pets , ,children and people with drinks etc.


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PostPosted: Wed Aug 08, 2018 9:58 pm 
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Joined: Tue Nov 13, 2012 6:14 pm
Posts: 105
Location: Portland, OR, US
Did Sherlock Holmes have a stereo?


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PostPosted: Thu Aug 09, 2018 2:06 am 
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Joined: Thu Jul 05, 2018 4:57 pm
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Location: Homestead, PA, US
Holmes never had a stereo, but with his keen powers of perception & observation, and his over the top discrimination skills imagine what a great audiophile he would have been. Or what a top notch quality control supervisor. Actually Edison invented the phonograph within the same years as the Holmes stories. I don't know if the phonograph was ever mentioned in any of his stories. The line "Elementary My Dear Watson", was never a line in any of his stories. That's a long story. He missed the LP record by around 60 years, Stereo by 69 years, CD by 94 years, and Super Audio CD by over 100 years. Poor guy? I don't know, because back then people probably heard live unamplified music making of one sort or another in the streets, pubs, concert halls etc.a hundred times more than we do in these modern times. Progress??


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