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LongtimeListener

Review - CD dynamics cut off by sound engineers therefore faulty by design

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15 hours ago, Addicted to music said:

@stereo coffee

 

so so what would a direct replacement for a 7805 if you think it shouldn’t  be used for audio?    Like you said there are many respectable manufacturers using it.  Or simular, it’s easy to just plonk one in the circuit and easy pcb layout.    It’s techbook designed.  Even many electronics engineers will just drop it in!   Just remember it’s standard throughout the industry where in SS some company disappear over night.

 

 

The LT3045 is being provided with heatsink on eBay , it has a footprint 

using 5 pins of which 3 are used. So whilst electrically a close equivalent allowing for 500ma of current it would require only small modification to suit,

namely the two outer pins requiring cutting and using the middle 3 which are

arranged the same as a 7805 , namely  Vin Gnd  Vout. On the downside supplied with heatsink, its pricing is about 10 times more than a 7805 .  But can be seen

it is a complete package requiring no external capacitors or resistors.

 

To install you would desolder the existing 7805, ensure the output was set for 5 volts as it is supplied adjustable to 15 volts, ensure the heatsink would fit and

solder in the middle 3 pins. Also observe the input voltage was no higher than 22v and output current was lower than 500ma... and you are good to go.    

 

 

It differs to the 7805 in important ways by having ultra low noise

and ultra high PSRR ( Power Supply Rejection Ratio )

Its datasheet is here:

http://www.analog.com/media/en/technical-documentation/data-sheets/3045fa.pdf

 

$_10.JPG?set_id=880000500F

   

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On 22/03/2018 at 2:17 PM, LongtimeListener said:

Hi all,

 

Since my quest for better sound has worked well, I sadly discovered that not only the musical detail of my recordings is revealed but also the flaws on at least one of my recordings, too.

I am owning that CD since 2003 and, although it was always a bit rumbling for my taste, I was quite happy with it. It is a very nice interpretation of the piece which I like a lot.

 

Now with my enhanced sound system I suddenly could hear a noise that is not belonging to the sound scape an orchestra produces. This noise is present in both the CD and the rip I used for the investigation below.

 

I took the time to investigate the issue and discovered, that the CD does not cover the total dynamic range, rather cut off the dynamic in multiple places.

 

I have attached my investigations below.

 

You can already see in the Total View that the sound waves don't fit in the range. Zooming in reveals indeed that the sound dynamics are tampered.

 

I am in the process to approach the reputable producer of this CD for an explanation and see what their comment to this is.

 

In times where those companies are worried about piracy I always wonder, why they cannot provide pristine faultless music to those who pay for it. This is in my eyes a big selling point and I am amazed why those companies not picking up this opportunity.

 

Cheers

 

Track 28 Total View.jpg

Track 28 Detailed View.jpg

Track 28 Cut Off Sound Curve 1.jpg

Track 28 Cut Off Sound Curve 2.jpg

Track 28 Cut Off Sound Curve 3.jpg

Track 28 Cut Off Sound Curve 4.jpg

Track 27 Total View.jpg

Track 27 Cut Off Sound Curve 1.jpg

Track 27 Cut Off Sound Curve 2.jpg

Hello,

 

if I may ask the OP a question. This thread is in the Product Reviews forum. I am not sure, what is the product under review?

 

regards

Grant

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Quote

if I may ask the OP a question. This thread is in the Product Reviews forum. I am not sure, what is the product under review?

Well, it is a classical music piece, it is very dynamic (Jospephs Legende, Staatskapelle Dresden, Giuseppe Sinopoli, P 2000) from the Deutsche Grammophon.

 

Sorry for the long break in responding, I was away.

 

Thanks everybody for the clever responses and thoughts.

I have written to Deutsche Grammophon (DG) and had a lovely time with their autoresponder. With other words they give a .... and are satisfied with their work and are happy bunnies up there in Germany.

 

To the discussion about the db range. Of course I do not listen to 120db music. My room noise measured usually is 5db with the audio system idle. There is some clock and fridge responsible for those 5db (and perhaps my stomach). A very loud classical passage, eg the sunrise of Zarathustra or the Josephs legend mentioned  above produces during a fortissimo a short peak of around 82db which one perceives as LOUD and stomach punching. Listen here if you like to Josephs Legende Finale

What I want to say is: there is no need to castrate a medium like the CD which is capable of a dynamic range of 120db by lousy music engineering.

 

The lesson for me is:

  1. Check the sound file in an editor after purchase
  2. Give it back to the shop where you bought it if it is castrated and
  3. Ask the money back

 

 

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10 minutes ago, LongtimeListener said:

My room noise measured usually is 5db with the audio system idle

trying to understand this.. I would think a quiet room would be well above 5dB… I doubt even a recording studio is that low

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Most likely 50db for most houses

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4 hours ago, Sir Sanders Zingmore said:

trying to understand this.. I would think a quiet room would be well above 5dB… I doubt even a recording studio is that low

Just as perspective.

I read a chart about typical noise ( db ) levels in various situations and a quiet library was 35-40 db.

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4 hours ago, Sir Sanders Zingmore said:

trying to understand this.. I would think a quiet room would be well above 5dB… I doubt even a recording studio is that low

He has an anechoic chamber in his house......

My purpose-built room with double gyp, green glue, acoustic doors with seals etc etc is mid to high 20s at night in a quiet neighborhood.

I would suggest his would be similar.

5db is VERY VERY VERY low.....

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Well, 5db is the lower end measured, it fluctuates between 5-10db. Yes, it is a quiet place where I live. In the night I sometimes want to open the window just to find them open already.

When listening to music, everything is closed to shut out any noise like birds etc.

I need that low noise floor as classical music has very quiet passages, sometime just rises out of a pianissimo.

Since real orchestras are much louder in average (they produce 120db) as me listening at home, those pianissimo parts would just not been heard.

I have to admit, though, that I did not measure with a calibrated sound meter. However, the measurement could be perhaps 5db off but certainly not 25db off.

 

A quiet library is quite noisy. Test it out next time and sit down with closed eyes. You will be surprised.

 

If you have 30db noise level in your "quiet" room you live in a very noisy place. 45db is what I have if eg a flute plays gently a pianissimo in an orchestral setting (microphone far in the room).

 

 

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2 hours ago, LongtimeListener said:

I have to admit, though, that I did not measure with a calibrated sound meter. However, the measurement could be perhaps 5db off but certainly not 25db off.

At such super super quiet levels, it could easily be this much off.... even expensive equipment could be.

 

2 hours ago, LongtimeListener said:

If you have 30db noise level in your "quiet" room you live in a very noisy place. 45db is what I have if eg a flute plays gently a pianissimo in an orchestral setting (microphone far in the room).

Yes, but only over a decade or so 300, 3000Hz.... this is why I asked how you are making the measurement (ie. which weighting scale, bandwidth, etc.) ..... although it's a bit academic - cos I agree there is plenty of range available to easily store any music signal ..... even if we did calibrate the quietest sound on the recording to be produced in the room at 5dB

 

 

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On 17/06/2018 at 9:25 AM, stereo coffee said:

The LT3045 is being provided with heatsink on eBay , it has a footprint 

using 5 pins of which 3 are used. So whilst electrically a close equivalent allowing for 500ma of current it would require only small modification to suit,

namely the two outer pins requiring cutting and using the middle 3 which are

arranged the same as a 7805 , namely  Vin Gnd  Vout. On the downside supplied with heatsink, its pricing is about 10 times more than a 7805 .  But can be seen

it is a complete package requiring no external capacitors or resistors.

 

To install you would desolder the existing 7805, ensure the output was set for 5 volts as it is supplied adjustable to 15 volts, ensure the heatsink would fit and

solder in the middle 3 pins. Also observe the input voltage was no higher than 22v and output current was lower than 500ma... and you are good to go.    

 

 

It differs to the 7805 in important ways by having ultra low noise

and ultra high PSRR ( Power Supply Rejection Ratio )

Its datasheet is here:

http://www.analog.com/media/en/technical-documentation/data-sheets/3045fa.pdf

 

$_10.JPG?set_id=880000500F

   

Nice find,

but I’ll be sticking to the noisy 7912/15 as they have a 1.5A capacity.

i don’t trust any SS on eBay.   I’d be looking at E14, mueser or RS etc that’s trusted.

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15 minutes ago, Addicted to music said:

Microsoft

−20.35dBA    😮

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Cool!  A room that you could actually sit in and listen to yourself listening to yourself.  

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8 minutes ago, Cafad said:

Cool!  A room that you could actually sit in and listen to yourself listening to yourself.  

Unlike some small manufacturers,  Microsoft, Apple Samsung etc have some of the biggest budgets going into R&D...  

 

20 minutes ago, davewantsmoore said:

−20.35dBA    😮

I doubt that you would be questioning that figure!   😉

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29 minutes ago, Addicted to music said:

I doubt that you would be questioning that figure!   😉

Well, I would ... Their result is over 400% quieter than the previous record.... and within reach of brown noise.   That's crazy.

 

.... but someone else (Guiness World Records) already did that for us.  👍

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2 hours ago, davewantsmoore said:

At such super super quiet levels, it could easily be this much off.... even expensive equipment could be.

Agreed.  Far more likely to be measurement error than than anything else. 

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3 minutes ago, Sir Sanders Zingmore said:

Agreed.  Far more likely to be measurement error than than anything else. 

.... yes, or 'measurement technique'

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