Showing posts with label podcasts. Show all posts
Showing posts with label podcasts. Show all posts

Sunday, December 09, 2018

Compressing spoken word audio for podcasts

What a terribly lax blogger I've been over the last few months; part of that was due to a couple fo trips to Saudi to finish building a facility in Riyadh (more about that to come; did you know that protective mains earths are not mandated there?!).
Anyway - I look after a couple of podcasts (just spoken word content) and for the longest time I've been using the Conversations Network Levelator to compress the dynamic range of each clip before I import them into Audacity and then edit/normalise them before exporting as an MP3 for upload. Imagine my horror when after switching to a new (old) laptop that I installed Mojave (OS-X 10.14) onto I could no longer use The Levelator; and it's a thing - lots of folks complaining online about it, but it's abandoware so what are you going to do?

 You upgrade the OS and some software stops working...!

 People listen to podcast in noisy environments; in cars, on the bus in earbuds and in other non-ideal listening environments. So, like talk radio the best thing is to compress the signal until there is almost no dynamic range and then normalise it to less than a dB under 0dBfs. Then it's a loud and punchy as it possibly could be and it'll be usable in bad listening situations. The Levelator was brilliant at doing this, but I thought I should at least roll my sleeves up and see how good the compressor in Audacity is, and blow me down it isn't bad!


After a bit of tinkering around with the ratio and threshold I arrived at these values as being best for audio that is peaking around -10dBfs (I'm a broadcast engineer, after all!) - it produces speech that still sounds OK, but has almost no dynamic range!

In this clip the band starts at around 2'15"

Sticking this .WAV file through the compressor set up (above) produced a very usable result which I then normalised before joining it to the rest of the segments of the podcast.

It looks like there is a lot of noise, but it's the sound of a very large room and on the speakers is sounds OK.

Friday, February 24, 2017

My favorite music podcasts

For me the last ten or twelve years has seen an almost 100% move to on-demand radio listening. The only live radio I listen to is the Today Programme on Radio 4 whilst having breakfast; I do put Six Music on at the workshop for the wiring guys, but for me (even shows produced for radio) are consumed as downloads.  Here are the things about music that I never miss.

  1. BBC Mastertapes - John Wilson presents artists talking about how they recorded a classic album. The show slips in two ("The A Side" and "The B Side") with Wilson doing the interview in the first half hour and then the assembled fans asking questions in the second. Wilson is clearly a music fanatic and never fails to engage with the artist. It comes from BBC Maida Vale and there are currently 74 hours for you to catch up on! Billy Bragg's "Talking with the Tax Man about Poetry" was the first episode back in 2012 and the glorious thing about it is I've discovered some records I never knew about and been really surprised by how much I enjoyed artists I thought were not my thing. Rufus Wainwright is a prime example. The artists always do a minimal arrangement of the well known numbers off the album their talking about and so of course the format tends to favour performers who can do it live.
  2. Between the Liner Notes - A podcast (not produced for radio) that takes some aspect of the music industry and devotes an hour to it. Really engaging and has a big radio rockumentary production feel. For me - a Gen X'er coming of age in the eighties the episode on MTV is required listening.
  3. Music City Roots - this is a "proper" radio show out of Nashville. I like it because Mike Farris has a show (which sometimes makes it into the podcast feed) but the main man is Jim Lauderdale who is a real champion of Alt-country and Americana.
  4. Sodajerker on Songwriting - Sodajerker is a songwriting team from Liverpool in the United Kingdom. Founded by co-writers Simon Barber and Brian O’Connor who, like most jobbing musos, have to suppliment their work with teaching and podcasting. They have had some great guests in their (so far 97) shows. In classic podcast fashion the length varies and the best one so far (for my money) has been Paul Simon although I've enjoyed all of them (check out ep.80 - Marcus Miller).
  5. The Bored-Again Christian podcast - a notable mention even though he stopped making shows five years ago. I discovered a few artists via this podcast; Sufjan Stevens and Danielson to name a couple.
Podcasting is the answer to the dumb mass-market HeartFM/TalkFM/LBC type radio. It's no coincidence that you don't get anything like this kind of treatment of musicians and who they do on commercial radio.

Saturday, April 02, 2016

The Engineer's Bench Podcast - tops tips for video

Next in our tips series - broadcast video.
Go to the website for a PDF of the notes.

https://youtu.be/18QR4E1yzKI



Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Saturday, July 25, 2015

The Engineer's Bench podcast - "KVM-over-IP and Data Encryption"

Hugh and Phil talk about KVM-over-IP systems with particular reference to Teradici and Phil's favourite manufacturer Amulet Hotkey. They also go over the basics of encryption with symmetric and public-key crypto.


Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Friday, April 17, 2015

The Engineer's Bench podcast - "Beyond Colour Bars"

Phil and Hugh talk about modern picture quality analysis and why good old fashioned colour bars are of little use to the modern broadcast engineer!



Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Tuesday, February 17, 2015

The Engineer's Bench podcast - "TV Colour 3 - using LUTs for calibration"

Hugh and Phil go over the practice of using a 3D LUT (look up table) to get OLEDs & LCD televisions closer to the Rec.709 gamut.



Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Saturday, December 06, 2014

The Engineer's Bench "Video Compression 101"



Hugh and Phil go over the principles of the Discrete Cosine Transform as applied to video compression and the differences between IFrame and long-GOP codecs.
Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Friday, October 24, 2014

Fibre 102; CWDM & encircled flux - The Engineer's Bench Podcast

Hugh and Phil talk about optical multiplexing as well as new methods for accurately testing fibre cables. A few tips on basic fibre cleaning as well.


Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Saturday, April 05, 2014

The Engineer's Bench Podcast: Intelligent Power Distribution

Simon Quill of Bryant Unlimited and Phil go over their range of network controlled, intelligently monitored power distribution units. Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Friday, February 14, 2014

System Design with Excel - The Engineer's Bench Podcast


Phil and Hugh go over a few tips and tricks for using MS Excel in the design of film & TV facilities. Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Saturday, December 28, 2013

DD-WRT and open source router firmware - New Engineer's Bench podcast

Phil & Tim Taylor go over some of the features of the DD-WRT router firmware and how they can be used to secure a home network.


Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Monday, December 02, 2013

The Engineer's Bench - hosting a video podcast

So for whatever reason Blip.tv have shut down the account that Hugh and I were using to host the RSS feed and media for the video podcast we do. Without any warning they shut off making any changes to the account (like re-directing the RSS feed and I hadn't been sensible enough to run it via FeebBurner) or even putting up a "so long and thanks for all the fish" clip up to let our iTunes & other podcast watchers know that the feed was dieing. Apparently we're a bit dry; they don't want engineering/educational screencasts, rather stuff that's more 'off the wall'. Ho hum - it was free (and free is never good) and so we've stretched to paying for hosting. 

From now on all Engineer's Bench goodness will be at it's own domain;

http://www.engineersbench.co.uk

What is worth noting is that only a minority of our watchers do so via iTunes/RSS - most folks now get it via Youtube, and so that has been unaffected and can still be found at the same old place.

We've been a bit slow recently but it's just the pressure of work. We have several planned:

  • KVM-over-IP - a technology whose time has come 
  • Software tricks and tips with Excel and other software for broadcast engineers 
  • Hardware pt.2 Raspberry Pi and NetIOM control boards
So hopefully 2014 will produce a return to form for your favorite broadcast engineering related video podcast!

Tuesday, July 30, 2013

Engineer's Bench Podcast - Photosensitive Epilepsy

Phil goes over OFCOM, DPP, Harding and other aspects of PSE.

Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Sunday, June 23, 2013

Engineer's Bench "Ultra High Definition - 4k & 8k Television" next podcast

Hugh and Phil go into the emerging standards for Ultra High Definition television.

Find it on iTunes, vanilla RSS, YouTube or the show notes website. My notes for this episode (with relevant URLs)

Monday, May 27, 2013

New Engineer's Bench Podcast "Traditional Video QC with Tektronix"

Hugh and Phil go through some of the principles of traditional video QC using the Tektronix WFM and WVR series test sets. Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Tuesday, May 21, 2013

Managing multiple identical sound devices in OS-X

I use Skype (although I may be looking for alternatives due to Microsoft's proved snooping - see here) and I like to have two sound devices so that the radio can keep playing through my speakers without me having to reach for volume control when I take a call. Also, when podcasting, I use the same laptop to run the presentation, keep the Skype call going and make the recording (that chews up three sound devices!). So along with the laptop's internal sound chip I have two cheap external USB dongles. Since they are identical they show themselves with the same name is all apps and invariably (especially if I've been away from my desk for a day and re-booted the OS without any of the USB devices attached) Skype picks up the wrong sound devices as default. It's trivial to change back but I always get it wrong ("..is the headset the first or second one"?!)

In Utilities is the Audio MIDI setup application (which I've never used before) where you can set "aggregated sound devices" - presumably to allow the same audio to play through several outputs? But - it allows you to create a proxy for a device and give it a sensible name.

So, I made new devices for the two USB sound dongles and gave them sensible names.
This now means that when I look at available sound devices in other apps (particularly Skype) I see things I can distinguish!



Saturday, May 11, 2013

Engineer's Bench podcast - new episode; "File based QC for TV delivery"



Hugh and Phil go over some of the basics surrounding delivery of TV shows as files. We then do a QC pass using Vidchecker. Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Saturday, April 13, 2013

Engineer's Bench podcast - "Digital Cinema"


Hugh and I are joined by Deluxe Digital's CTO Laurence Claydon to talk DCI, DI, projectors and Dolby ATMOS. Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Thursday, March 28, 2013

The Engineers Bench podcast - shared storage for film & TV

Hugh and Phil are joined by Rupert Watson from root6 to talk about SANs, NASs and shared storage for film and TV. Find it on iTunes, vanilla RSS, YouTube or the show notes website.

Shared storage for film & TV - the next podcast

Hugh and Phil are joined by Rupert Watson from root6 to talk about SANs, NASs and shared storage for film and TV - see the wiki