Still getting static, Mac OS 10.4.11

[khoffcran]

Hey Bill - No, the problem pre-dated the ART interface. I had a Numark TTUSB turntable when I first encountered the problem. The reason I switched to the analog TT / ART interface setup was because I believed the intermittent "static" was caused by EM interference from the TTUSB, either because of shoddy electronics, or because of the open non-detachable RCA plugs that weren't in use when the USB cable was being used. I had hoped to defeat the problem with an analog TT and A/D pre-amp. And, in fact, the signal going into Audacity is much, much cleaner. But I still have the static problem, although as of now only when using the USB cable.

Now, the idea that the USB cable might be faulty is definitely worth checking out. I'm using the same USB cable with the ART interface as I was with the TTUSB. That is, I'm using the USB cable supplied by Numark.

And, in calling the problem "common" because similar problems appeared to have been encountered by a few users - among thousands using the program and identical hardware and operating systems without a hitch - was probably imprecise language on my part. But there are a few others out there with a problem that sounds very, very similar to mine.

And thanks to those who suggested I step up to Aud 1.3.12 from 1.2.5. While it didn't fix the problem, it got me to get used to 1.3.12, which I agree is superior in all respects. As an example, the noise reduction is now a relatively subtle tool, as compared to the blunt meat axe of 1.2.5. Although the 1.2.5 noise reduction was effective at removing vinyl surface noise, it left such significant electronic artifacts - even when used at the lowest level - that it really left a Hobson's choice, particularly on sounds like acoustic guitars, that it tended to obliterate altogether. The combination of noise reduction at 10dB, click removal, and normalization/re-amplification back to 0dB gives a good result, without introducing the distortion of electronic artifacts.

Thanks, Keith H, NJ / USA

[billw58]

As an example, the noise reduction is now a relatively subtle tool, as compared to the blunt meat axe of 1.2.5. Although the 1.2.5 noise reduction was effective at removing vinyl surface noise, it left such significant electronic artifacts - even when used at the lowest level - that it really left a Hobson's choice, particularly on sounds like acoustic guitars, that it tended to obliterate altogether. The combination of noise reduction at 10dB, click removal, and normalization/re-amplification back to 0dB gives a good result, without introducing the distortion of electronic artifacts.

You sound like you're quite serious about this project. Not to knock Audacity but you owe it to yourself to check out Brian Davies' ClickRepair and DeNoise tools. They have a 21-day free trial. http://www.clickrepair.net/

-- Bill

[waxcylinder]

... you owe it to yourself to check out Brian Davies' ClickRepair and DeNoise tools. They have a 21-day free trial. http://www.clickrepair.net/

I second Bill there - the package costs a little but is just a little short of magical in its effectiveness, and is very easy to use. See this sticky thread: http://forum.audacityteam.org/viewtopic.php?f=28&t=1994

And yes Keith I would suspect somewhere in the USB chain - the cable or the socket.. Can you try another USB socket - you're not using a USB hub are you?

WC

[bgravato]

I think he said earlier that he's not using an usb hub.

I've put the oscilloscope probe on the usb's +5V of my macbookpro and the oscilloscope screen showed what seemed to be more like a cloud than a wave. The amount of high frequency noise going there is mesmerizing. My Art Dual Pre seems to filter well that noise when powered from usb, I'm expecting other ART products to be on the same level filtering the noise from power supply. Anyways since the problem was present on the other usb turntable I guess it's not a problem with the preamp here...

[khoffcran]

Thanks Wax, all - I've tried all three USB sockets on the iMac5,1, and eventually gotten the same results. No, I'm not using a hub.

Hopefully tonight I'll be able to try some more recording and gather some more data. So far I haven't had any problem with the pre-amp to RCA outputs to 1/8th" input. I would like to switch out the (arguably faulty) USB cable and try the USB socket again, to see what happens.

I'll also try the Brian Davies' software as suggested, although I have been getting acceptable results with the combo of noise removal / click removal / reamplification in Aud 1.3.12. Of course, before you all turned me on to the superiority of 1.3.12, I was satisfied with 1.2.5. So, who knows? And I'm still waiting on the delivery of an Ortofon 2M Red cart to replace the stock Denon cartridge that arrived with the analog TT.

This puts me in mind of the sci-fi concept of why it's useless to launch an extra-solar system space exploration mission: Continuing improvements in technology will always result in a later mission overtaking an earlier mission! (Of course, the logic is ultimately flawed, because you can't gather enough data and experience to maximize the improvements in technology without the experience of the earlier missions).

[Sorry if I'm stereotyping others who share my interests as being middle-aged men who read a lot of sci-fi as adolescents (and perhaps cointinue to enjoy the occasional LeGuin/Dick/Heinlein read), but I'm guessing I'm not far off!]

Keith H NJ / USA

[billw58]

[Sorry if I'm stereotyping others who share my interests as being middle-aged men who read a lot of sci-fi as adolescents (and perhaps continue to enjoy the occasional LeGuin/Dick/Heinlein read), but I'm guessing I'm not far off!]

Well, you pegged me!

You might want to check out Roger Zelazny, Kate Wilhem (her SF from the 70's and 80's, not the "Barbara Holloway" mysteries), James Tiptree Jr, David Brin ("Earth" and the two "uplift trilogies"), Vernor Vinge and Kim Stanley Robinson (Mars trilogy) (if you haven't already ).

-- Bill

[khoffcran]

Bill, Wax - Thanks for the tips on Brian Davies. I'm going to download the tryout software when I get home. I did a little background reading on him. Is this guy for real? He's like the Renaissance man of mathematics, music and code-writing. Who is that smart? And that active? His list of published works is utterly ridiculous.

Thanks again,

Keith H NJ / USA

P.S. - Lest I get kicked off by a SysAdmin for being off-topic, my last words. Of course I know Zelazny, but not the others. (I felt compelled to use "lest" to impress alla youse real English speakers. Northern New Jersey is not completely bereft of the proper use of our common heritage!) And it might interest you, Wax, depending on your age and tastes, that (although it's all available on CD), some of the vinyl I'm archiving is Joy Division.

[khoffcran]

Hello All - A few things. As I write, I'm recording from vinyl through the ART USB interface, and then using a NEW USB 2.0 cable into one of the three native USB sockets in the iMac5,1. The sound is superb, and as of now there has been no static interference. If that continues to hold, you have collectively solved my original problem, for which I am very thankful. Still more, I am using Aud 1.3.12, for which I have additional thanks. Yet more, I have downloaded Professor Emeritus Davies' ClickRepair. By its reputation, and by demonstrations at his site, I have every reason to think that will open up for archiving entire sections of my collection - jazz, classical, ambient (Eno, Cage, John Hassell etc) - that I thought (because of its extraordinary dynamic range) could only be reacquired through CD. Because I approach this project not primarily as a technophile nor an audiophile, but rather an eclectic lover of great music, that is the greatest gift of all.

(Of course, if I suddenly get static interference, or ClickRepair is less effective than I'd hoped, all this warm and fuzzy effusion to my new Anglophone friends around the world will be down the tubes. )

Keith H NJ / USA

[khoffcran]

OK, the results are in:

1. I've now recorded about 200 minutes of vinyl with the new USB 2.0 cable. No static. Problem solved. And, like every successful solution, in hindsight it was obvious.

2. I've processed 40 minutes of raw input with ClickRepair. The source material was not good. The results are beyond anything I could possibly have expected. It's almost as if the combination of a quality analog TT, the ART USB interface, a fresh USB 2.0 cable, a 2006 iMac, free Audacity software, and a $40 software suite, have given me the ability to remaster in my little computer room.

3. The project is important to me, and its failure was frustrating, because my immediate aim is to revivify a vinyl collection of a friend / neighbor whose son died of cancer last year, and who will get some happiness when I deliver a set of CDs with music she hasn't heard for a long time.

Thanks All

Keith H NJ / USA

-30-

[waxcylinder]

... Lest I get kicked off by a SysAdmin for being off-topic ..

I wouldn't worry too much, the forum elves are just as bad at going off-topic at times

Seriously though, I'm glad youv'e got your recording chain working so well now. You won't regret getting ClickRepair, I had one LP that was totally unplayable because of all the clicks and pops (the Scott Joplin recordings by Joshua Rifkin). After ClickRepairing it, it now sounds pristine again. Sadly I only found out about CR after I had spent two weeks manually restoring my wife's favourite LP which is not available at all on CD - all that hard work and CR could have done it in a minute or two - d'oh

You might be interested in looking at my outline workflow for LP and tape transcription:
1) Record one side of an LP/tape - aiming for a max level of c. -6.0 dB (Audacity set at 44.1kHz 16-bit stereo)
2) I either mark the approximate track/song starts as I am recording by placing labels (CTRL+B will mark the current cursor position or CTRL+M will mark the current record/playback position). Or after the recording I zoom to fit the entire project and then I can usually visually spot the track/song start points and label them approximately.
2) Export a single WAV file of the project (32-bit)
3) Process the WAV file through ClickRepair (32-bit)
4) Import the repaired WAV file back into the still open Audacity project
5) Delete the originally recorded track in the project - this leaves the label track and the cleaned up audio (still in synch.)
6) Edit the inter-track gaps: fade-out/proper silence/fade-in and possibly shorten the gap to clean off the LP surface noise
7) Adjust labels to exact positioning
8) Use the Amplify effect to bring the level up to -2.0 dB (0 dB can clip/distort in some players). I use Amplify versus Normalize as in Audacity Normalize works on each stereo channel separately and thus can alter/damage the stereo image.
9) Export Multiple to create a set of WAV files (at 44.1kHz 16-bit PCM stereo)
10) Exit Audacity
11) Repeat for side-2 of the LP
12) Back-up the set of WAV files (2 copies to 2 external USB disks)

Note that nowhere in this process do I bother to actually save an Audacity project. Also note that stages 2 and 3 give me temporary “backups” of the whole project that I can revert to if necessary. The only time I save the project is if I have to leave it part way through overnight.

WC