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Old 10-19-2015, 07:35 PM
George Frankly George Frankly is online now
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Default Any audiophiles in here?

Probably a long shot, but what the hell.

I started doing car audio with my older brother when I was about 14, and got hooked. Throughout HS and college I did a lot of car audio builds, and then near the end of college I started doing home audio. Initially it was a Denon receiver and Klipsch speakers. Then I tried Magnepans and upgraded to an NAD integrated amp and CD player, and then some really nice Avance bookshelf speakers, which I still have. Bought a McIntosh pre-amp and amp at some point.

And then I got into DIY. I built a tower speaker (sort of like the Seas Thor) with a pair of 7" woofers and the matching Seas Millennium tweeter. And all was going pretty well.

But back in around 2010-2011 I started re-thinking high efficiency and, specifically, horns. In doing so, I also started re-thinking bass and the use of multiple subs. And after a lot of thinking, a few months back I started buying gear. So now I'm building a totally new setup.

I started with a pair of Dayton Audio 15" subs driven by a Crown amp, fed by a Behringer Feedback Destroyer that's basically a big EQ. And then a friend offered me an SVS sub for a great price, so I added that. Three subs.

Then I found some JBL 14" woofers (not subwoofers), they are JBL LE14H-1 if that means anything. I *think* I can run two per side, so that's four 14" woofers to handle 70Hz to 750Hz. And then for the treble I have some JBL horns with beryllium drivers (model 435Be, looking for the matching 045Be currently), really nice. All being fed by a signal processor to do all the crossover/EQ work (White Instruments Paramedic 26). And I have a measurement system with which to tune. For now it's all in really crappy cabinetry just to see if it'll work. Still have some dialing in to do, but it sounds great. It's got great dynamics, and it will get loud and sound great at high SPL, and those were the real goals.

Hoping at least a couple others are into audio at some level. Happy to answer any questions about the system, or audio in general. Like why use three subs, etc.
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Old 10-19-2015, 07:44 PM
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Rex Ryan's pet coyote Rex Ryan's pet coyote is offline
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Are you listening to 128 kbps mp3s on this system?
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Old 10-19-2015, 07:53 PM
George Frankly George Frankly is online now
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Originally Posted by Rex Ryan's pet coyote View Post
Are you listening to 128 kbps mp3s on this system?
It depends. I have a decent CD player (brand is NAD) for high-quality sound. I'm not above using mp3s, I rip at 192kbps, a compromise of sound quality and file size. I need to get a decent DAC in the stream though, haven't done so yet. And sure, I'll throw on streaming audio sometimes. So I'm not such a snob that I let the bit rate get in the way of listening to good music.

Also, a lot of the music I listen to wasn't exactly recorded all that well. I like the Yeah Yeah Yeahs, Built to Spill, etc. No matter what format, those bands won't sound all that hifi. I won't listen to an album just because it was recorded well, for me it's music first and recording/playback quality second. Listen to how accurate that distortion sounds on my system.

I did try a record player. Bought a decent Music Hall some years back. Didn't see the allure, sold the record player. I read the redbook specs on how music gets digitized for a CD, and I'm sold that CD quality is really, really good.
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Old 10-19-2015, 10:57 PM
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Is clipping on CDs still a thing?
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Old 10-20-2015, 12:08 AM
George Frankly George Frankly is online now
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Is clipping on CDs still a thing?
Clipping is an issue of amplification. I'm not aware of CD players clipping. Clipping is still a thing with amps, but not as much as it used to be. One, amps are cheap, so it's cheap and easy to buy as much power as you need. Two, some modern amps have protection circuits in place.

If an amp does clip, it could ruin your speakers. If things start sounding pretty ragged, turn it down. I've actually never blown up a speaker.
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Old 10-23-2015, 02:02 PM
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I like nicer sound systems and stream/play in the highest quality I can.

Earbuds: Klipsch noise cancelling
Headphones: PortaPro (lighter on-ear) and Sennheiser padded over-ear
Car audio: Was ELS in my TSX, have Bose in my mazda
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Old 10-23-2015, 04:32 PM
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Originally Posted by George Frankly View Post
I rip at 192kbps, a compromise of sound quality and file size.
Uhhh, can't you just go buy a 2 TB hard drive? Do you really have so much music that you need to worry about file size? I have like 300 CDs on my computer and they're all the highest quality that Windows Media Player would let me rip them at, plus everything else on my computer including family pictures and videos, and I'm using like 500 GB total.

Or, did I miss something. Maybe I did. TL;DR.
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Old 10-23-2015, 04:33 PM
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Is clipping still a thing in hockey?
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Old 10-24-2015, 12:24 PM
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But if you're a real audiophile and you read further about it, you'd realize how not-so-good CD audio really is.

Although the mathematical principles behind the CD audio format are sound (no pun intended), in practice things don't go so well because the theoretical concepts involved are too computationally expensive to fully implement.

The first shortfall in practice compared to the theory is the brick wall filter that is supposed to remove all frequencies above the Nyquist cutoff of 22.05kHz. Without removing those frequencies, one loses the ability to accurately reconstruct the continuous waveform from the discrete 44,100 samples per second.

But in reality there is no such thing as a true brick wall filter, i.e. completely removing all frequencies above the cutoff while leaving all frequencies below it untouched. A practical filter is going to introduce some distortion below the cutoff while still leaving something above the cutoff. The human hearing limit of 20kHz is not far below the chosen Nyquist frequency of 22.05kHz, so some filter-induced distortion can still leak into the human hearing range.

The second (and bigger) problem is that digital-to-analog converters (DACs) in consumer hardware don't even use the proven math for reconstructing the continuous waveforms, because it's too computationally expensive. Mathematically accurate reconstruction of the waveform would involve sinc functions and Fourier transforms and other math I don't understand, but that's too much for a typical $10 DAC chip to do in real time so they resort to cheap interpolations instead.

The good news is that improvements in technology are enabling the CD format to produce results closer to its theoretical ideal. In the early days of CDs, the brick wall filters were analog, and they introduced lots of distortion into the audible range so CDs back then sounded harsh. But now they're using digital brick wall filters which can perform much closer to the ideal, and they can keep improving those filters by throwing more computational power at them and tweaking the algorithms.

On the playback end of it, some high-end DACs are incorporating field-programmable gate arrays (FPGA) so they can be more true to the math that is involved with reconstructing the analog waveform. And there is software like HQPlayer that utilizes the processing power of multi-core PCs to perform that math to upsample to high rates like 192kHz or 384kHz, thereby leaving the DAC with less work to do with filling each gap between samples (provided your DAC can accept a sample rate that high, of course).
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Old 10-24-2015, 12:40 PM
George Frankly George Frankly is online now
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Quote:
Originally Posted by ActSciMan View Post
Uhhh, can't you just go buy a 2 TB hard drive? Do you really have so much music that you need to worry about file size? I have like 300 CDs on my computer and they're all the highest quality that Windows Media Player would let me rip them at, plus everything else on my computer including family pictures and videos, and I'm using like 500 GB total.

Or, did I miss something. Maybe I did. TL;DR.
I keep lots of songs on my phone. I do stream some, but like to have some stored. I think it's about 35GB at the moment. I have an iPhone with 64GB, my next phone will probably be 128.
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