Friday, July 10, 2015

Reducing Echo, Sound Reflections or Reverb from audio recordings

Since I come across audio issues in videos quite often, I thought I'd write a quick article explaining about sound reflections (echoes) and some tips on how to control them.

Correcting echo in recordings?!?!

Ok, the title is a misnomer.  You will have a VERY hard time reducing echo from completed audio recordings.  Echo or sound reflections are exactly the same pitch as your voice, and much harder to remove from recordings [Ed - as compared to background noise, see below] without affecting the quality of your own vocals.

What you do instead is control your recording environment before you record.  Here's a good quick video someone created, with tips on controlling your recording environment:

https://www.youtube.com/watch?v=daa-Qp7C3qE

If you must reduce echoes and reflections in the recordings, I give some quick tips at the end of the article.  But let's assume you did a test recording or can re-record first.

My first attempt - control reflections in my bedroom.
desk for recording on right with blanket on desk,
pinned a towel on the curtain behind desk over the wall.

Controlling the environment - My first attempt

When I first tried recording, I was working at my temporary desk in my bedroom.  I planned to make many courses, so I needed to have great quality.

So I in a similar way to the video's first section and recorded in my bedroom.  I put blankets on the walls with thumbtacks, a towel on my desk, pinned a towel to my curtains behind my desk with clothespins, etc. See the image "My first attempt" to the right.

It worked great, in spite of wooden floors and bare ceiling.  But once I moved my desk back into my living room, I didn't want to record in my bedroom any more -- and I wanted to see if I could do even better.

Second attempt - works beautifully

PVC frame.
The audio quality in my living room is abysmal.  It has an archway to the kitchen, and a long hallway.  Recordings outside the booth sound like I'm shouting on stage in an auditorium.  I honestly started looking for the automatic "reverb" setting that must be on the application I was recording in.

Then I built a PVC booth, which is more similar to the 2nd part of the video above -- a dedicated cubby with padded walls for recording.  In the video, he uses mattresses and blankets and says that you can cover all 4 sides.  That's what I did.

First I drew myself a sketch and decided how tall I wanted the booth, so I could figure out what types of connectors I'd need, and how many pieces of pipe.  I already owned a PVC pipe cutter -- I brought that to the store with me along with a tape measure and fine-point permanent marker to mark lengths of pipe.

I hung heavy duty moving
blankets from the frame,
and draped some garden
cloth over the top.
The booth is made from inexpensive 1-inch PVC pipes, and a bunch of connectors.  I cut pipes to the right length for the tall poles while in the parking lot, so they would fit in my little hatchback.  When I got home, I finished cutting out all the smaller pieces and built myself a booth that's about 6'4" tall (a foot over my head) and about 4 foot by 3 foot.

I bought 3 thick "heavy duty" moving blankets to hang from it, and I found the perfect sized clamps to hold up the blankets at a "dollar store."

Assembly was quick.  I didn't glue the pipes so it can be disassembled, but it can also skew, so I have it in the corner of the room where I can nudge it towards the wall so it has no place to go.  You could build a better booth, I'm certain!  I just needed a place to hang my blankets.  I also could change how it's assembled to make it larger inside if I want to, but I haven't needed to.

This booth works much better than the blankets strewn around the room, especially considering it's in the worst room in the house!

Sound booth interior:
clamp lamp, mic with pop
filter on stand.
Inside the booth I have a mic stand with a mic, and pop filter.  I have a clamp lamp I already owned to help me see notes or just not be in the dark within the booth.  I use clothes pins to pin up notes, or I have a small flexible camera tripod and an iPhone adapter so I can hang my iPhone up and read notes from the screen.

Next I want to make a version for when I'm sitting at my desk doing screencasts.  I've also considered ways I could possibly use the current booth materials to create a greenscreen for video recordings.

What about background noise?

The sound of machine fans running, cars driving by, my chickens clucking, or just the mic's noise with no other desired noises going on is called "background noise."

To get rid of it it's called "Noise Reduction" -- you can take a (free) application like Audacity.  You record about 30 seconds at the beginning or end of each lecture without talking.  That's a "noise profile".  Then you first have to select the noise profile section without talking and tell Audacity that "this is the background noise profile"  Then you tell it to filter that out of your recording.  Because that sounds different from your voice, that's pretty easy to do.  [Ed -- see Noise Reduction in Audacity or watch this video.]

Another way to reduce background noise is to get closer to the mic.  The closer you are the easier it will be to filter everything else out.

I already recorded, now what?

If there's no option to re-record with more control for echo and reflections, you might be able to play with the noise filter, or a sound gate, and reduce the reflections.  But it takes a lot of time and experimentation to get the settings right for you, your voice and your environment.

Go forth and record!

It's always best to record the cleanest, clearest audio you can right from the start and save a lot of time on the editing & audio processing end.  If you have a lot of audio to clean up, it can take hours to fix minutes of audio.

So try recording in your room before & after the blankets, try further and closer to the mic, try with and without a pop filter, and use headphones so you can actually hear your recording more accurately than through computer speakers.  Side-by-side you should be able to tell the difference in the recording quality.

Test!  Test again!  If you test and think you have it all right, then go back to record the next morning -- test again.  The worst things are simple, like the pop filter moved and now is against the mic, or you forgot to turn the mic on, or you are dehydrated so you have dreadful mouth noises today, or you can hear the rain outside but it wasn't raining yesterday.  Test & listen to it.  Play with the editing commands with a short test piece.  Are you happy with how it came out?  Did it take too much fussing and still not sound very good?  Tweak the equipment, recording settings & environment until everything is right for today.

And feel free to ask for help.

Tuesday, March 31, 2015

My first Udemy Course on Tricky English Words!

Man sitting at desk writing in a journal, only his arms, desk, notebook, pen and a computer in the background are visible.  A thought bubble rising up from the notebook depicts "bear feet": a picture of someone wearing bluejeans and brown fuzzy clawed monster slippers.
Course Image: "Bear Feet"

I'm so excited to have my first course on Udemy.com: "Improve Your English Vocabulary with over 70 Tricky Words."

Mistakes can be embarrassing -- and for some people it can cost them a job opportunity, lose opportunities for a promotion, or cause them social media anxiety.  If you ever get confused between which spelling of "capital" to use (or is it "capitol"?), if you get embarrassed when people correct your word choices ("you mean 'accept' not 'except'"), if you don't know when to kick your autocorrect for adding an apostrophe to "its," this is the course for you! 

I've leveraged my creativity and brainstorming capabilities to find innovative ways to remember different sets of words and tell which is which, to make it easier to write and proofread what you've written.
  • Look more professional
  • Avoid miscommunications
  • Sharpen English writing skills
  • Say what you mean
  • Make a great first impression
In 24 closed-captioned lectures spanning about an hour and a half, you can learn mental tricks and stories to tell apart over 70 (currently 92) tricky words.

People who have found my course helpful:
  • English language learners (intermediate)
  • Businesspeople
  • Native English speakers who have writing anxiety
  • Homeschoolers
I have over 2,000 students in my course, and some great reviews.  I look forward to helping more people.

Feel free to watch my promo video, below, and my blog readers get a special discount!  Click here to view the course information, preview lectures, etc. and it will load a discount coupon for the course in case you're interested (it's currently $29,  and the coupon makes it only $5).  


Monday, April 8, 2013

Are you hungry?

One of the things I haven't discussed on this blog is food and, by extension, hunger.

Today is Blog Against Hunger day... so here's my 3 cents:

There's hungry -- those with nothing of any substance to eat.  And today is mostly dedicated to them.  We like to think these people live far far away, but they're here in our community also.

But then there's hungry -- those with an insufficient amount to eat.  And sometimes they're our neighbors.  You pass them in the street, in the supermarkets.  The mothers who go hungry to make sure they feed their children.  The families who can barely buy anything, and must make do with as little as possible.

And there's the invisible hungry -- those with much more than enough to eat, but it's is sub-standard or lacking in vital nutrients.  Unfortunately, that's most of us.  We may think we're eating well, but what we're eating isn't really food  at all.  Reconstituted foods, over-processed foods, foods that had to be "enriched" because the nutrients were stripped out and then added back in through "nutrients" made in factories.  Foods rendered unrecognizable to our metabolism through science.  Free-radicals that are costing our health.  We eat more and more because underneath all that massive food we're eating there's very little of actual substance or sustenance.

Those of us in the invisible hungry could improve our food intake, and fight for food freedom & responsibility -- then we won't be hungry anymore, and the food industry will respond to our demands and become more responsible.  That improves the food available to those who don't have a sufficient amount to eat who live next door, too.  Then together, we can help people find ways to grow good food locally, improve their soil, improve their water use, so that they can eat where they live, and live where they eat.  That's been the answer for the vast majority of human history: technology cannot change the fundamental fact that this is the healthiest way to eat, that it's how our bodies evolved to eat.

For more information on Food Freedom, I'm always posting on my Facebook timeline on this topic, but check out my Fairy Goddaughter, Linda Borghi of Abundant Life Farm.  She's got it all down and helps people learn about growing their own food.  She's been helping people in Africa grow their own food and become self-sufficient.

Namaste,
Criss

Friday, September 21, 2012

The Game of Essay Writing

So many of us have kids that are hyper-focused on games.  So here's an example of both an essay and how-to write and organize an essay for a kid who loves gaming (written for my son).

One of the problems is the word "essay" -- once we have the skill of "writing an essay" down it ends up being used in emails, in brochures, in business plans, in letters of request or recommendation -- the same skills we call "essay writing" in school is even used for short-form facebook posting through to long-form thesis or dissertation writing.  But we call it an "essay" which makes it daunting.  We could call it "Writing an Instruction Manual for a Game System".  We could call it whatever -- it's just "good writing technique".  Or if you will a "sandwich writing technique".  Or best of all "writing for the reader".

Monday, June 20, 2011

More on Writing

Writing Fiction For Dummies
Excellent Fiction Curriculum

I've actually come across the National Novel Writers Month  ("NaNoWriMo") and decided to participate both this summer, if possible ("Camp NaNo") and in November when the "official" NaNoWriMo kicks off.  For adults, the goal is to write a 50,000 word novel in 30 days.  You are allowed to do pre-writing tasks before the event, in fact it's encouraged (and helps you write a quicker, much more cohesive project).  There are no prizes, although winners might get special offers from sponsors.

They have NaNoWriMo YWP (young writer's program) where you (the instructor or parent) helps a child set a word-count goal that's within reason but still a stretch for them, and they can also set off and write along side you (if you participate).

Friday, June 17, 2011

Fruits of his Labor

Photo by Jo Christian Oterhals via Flickr
When we were discussing homeschooling, my son's father gave him an assignment: write a 1200 word essay on the pros & cons of homeschooling.

This is the same 13-year-old-boy who would write exactly 3 5-word sentences if that's all he was required, whose IEP writing goal in 8th Grade was to write 3 paragraphs.  His main problems being a huge reluctance to write due to handwriting issues when he was younger, years of handwriting remediation, and having convinced himself (and others) that he "can't" write.  His paper comes out with approximately a 10th grade readability level!

Monday, April 25, 2011

I live in a Pig Palace

I don't remember how young I was.  Much too young, I'm sure.  I was probably caught between the trap of being a preschooler, an only child, having a "pack rat" father and a tidy mother, and never having been taught how to declutter and purge.

Inevitably I got to an age, probably 5 or 6 at most, where I was expected to have developed cleaning habits and skills in the face of a daunting amount of STUFF in a room much too large for someone my age to be fully in charge of.

Saturday, April 2, 2011

Autobiography

I think I'd like to use this absolutely brilliant "Portfolio" assignment for an 11th grade writing course (following a creative writing course), although I'm considering working it in sooner rather than later and doing the assignments for myself alongside my son working on them. The end-product of this year-long assignment is a publishable autobiography. The teacher who created this curriculum packet has had a great amount of success with other teachers adopting it as well, including foreign language teachers, and has used the assignments in literature classes as well (where you write the portfolio assignment "as if" you are a character in a book).

Creative Writing

Hamlet on the Holodeck: The Future of Narrative in Cyberspace
Hamlet on the Holodeck
If things in homeschooling, assuming we homeschool, go the way I plan, then my son's remedial writing will focus strongly on expository writing skills. Thinking far ahead, in ways I probably shouldn't, I think the follow-up would be dedicated creative writing. I took creative writing twice in High School and again in College, and I believe it strengthened my overall writing abilities tremendously. My son's reading interests are very close to mine back then, and I can explain to him the importance of having the skill of creative writing. It doesn't hurt that he's read some of my own fantasy stories and liked the style and thought it was good.

The Myth of "Socialization"

How much "socialization" does a child get in school? How much does a homeschooled child "miss out" on this so-called socialization.

First, the term "socialization" makes it sound like something deliberate, like animal husbandry. You pair kids in the corral for purposes of "socializing them." Anyone who has been to a school knows this is simply not the case; the schools group children together based on their classes, which are usually based on their abilities and at the starting level children are grouped simply based on their chronological age. If we were to purposefully socialize our children, wouldn't we pair or group them based on common interests?

Sunday, March 27, 2011

Child-Centered Teacher in UK Sacked for Saving 5 Boys' Education

Here it is, another anecdote from the good-teacher vs. bad-system movement:

5 students that are completely beyond help, and one teacher who decides to put them first. So much so that she uses their first names and their group nickname in a fictional tale about how people in a downward spiral can turn everything around if they want to. The boys identify with the characters, I'm sure it's partially because their first names are in the book, and they actually read it. The students do so well, are so inspired to learn and straighten their lives out, that they all go on to post-secondary education. The teacher is given promotions and kudos.

The teacher's husband, without her knowing, puts the book up on the Internet and the teacher gets canned. Read more...

This is how we reward the world's best teachers.

The importance of missing the mark

Pay for performance. It's currently a pretty hot issue. There's plenty articles telling us how poorly it's working, too. A great summary of US and UK tests on pay-for-performance is at the Telegraph. Basically, giving teachers incentives for improving test scores of $3000-$15,000 is not effective in increasing the children's test scores.

I'm sorry, but everyone's completely missing the mark here!

Making History

So as adults, I ask how much of what you learned in History lessons do you use today? I'll say I use more of it in helping my children with their classwork -- and that's the be-all and end-all of the facts and details I was spoon-fed in K-12. In SPITE of the fact that I've done historical re-enactment! In other words, absolutely NOTHING I learned in K-12 classes helped me EVEN with my hobby of historical re-enactment! Shame on the school system!

Math - to Curriculum or NOT to Curriculum

My son loves math. He's got a lot of talent for math, and frankly I think schools and big textbooks hold him back. I don't really feel confident teaching Algebra, even though I think I remember all the important basics and could always brush up from resources online. However, I'm very confident that my son can almost teach himself Algebra with the right tools and materials.

Remedial Writing

My son has had quite the journey regarding writing challenges ever since Kindergarten. He was identified as gifted, but also earmarked for needing occupational therapy (OT) for handwriting. So in 1st grade, he went to a gifted program and had 1:1 instruction to try to correct his fine-motor issues.

I have a genetic nerve disorder, and perhaps my son is not entirely in the clear. However a neurologist didn't find anything in particular wrong, and so the OT continued until 7th grade.

Due to his continuing difficulty with writing, my son avoided writing like the plague.

Quality Schools Part 2

Don't forget to read my Part I on this topic!

I didn't realize that one of the books I already own has a whole chapter (a long! chapter) dedicated to quality schooling. So I started reading The Quality School (William Glasser) and the introduction referred back to that chapter in Choice Theory, so I went to the chapter and read it.

I'm so impressed with this concept, I want to make it a cornerstone of my homeschooling experiences.

Wednesday, March 23, 2011

William Glasser & Quality Schools

I can't wait for my books that should be arriving on Quality Schools. I already have several of William Glasser's books: Choice Theory, Counseling with Choice Theory and The Language of Choice Theory. The Quality School is going to be arriving on my doorstep shortly. Aside from how you treat your student (in my case homeschooler) in terms of verbal contact, there's a basic difference in how children's learning and work is treated that returns dignity, respect, and a higher level of useful expectations to the children.

Basically, children work at their exercises until their work is an A or B level. Barely-passing work is no longer accepted.

High School Homeschooling

Right now it's on the table with my family whether we're going to homeschool my son for High School. I tried to contain myself. I've tried pacing myself. I've tried just gathering information and thinking, but I think I've gone overboard with planning.

I think that homeschooling should be about what's right for a particular student.

Radio Show Pulled

Not-so-breaking-news: I pulled Let's Heal the World Together, and I'm saving the idea (and the logo) for a later date. I pulled it before I had surgery in December last year (2010). This has freed up several hours of my week, which I'm currently dedicating to my family and my own health.

Saturday, August 14, 2010

Moving Radio Show Posts

I don't think many people are reading my posts here, so I've decided to take advantage of the BlogTalkRadio blog feature to do pre-show-notes introducing the topic of the show. The traffic there is much higher and if someone tunes in to the show-in-progress maybe they'll see my "thoughts" in the previous blog post and get the drift of what's going on on the show.