<![CDATA[Counterpoint Sound Worx - Blog]]>Thu, 27 Feb 2025 16:44:09 -0800Weebly<![CDATA[7 Books for DAW-based Audio Engineers in 2020]]>Mon, 13 Apr 2020 07:00:00 GMThttps://www.counterpointsoundworx.com/blog/7-books-for-daw-based-audio-engineers-in-2020

7 Books for DAW-based Audio Engineers in 2020

Introduction

The internet is a great place to absorb content and to answer questions. However, there are times when we can create more work for ourselves by not going directly to the source. I find that books are great tools for both reference and context. I assembled this list, in no particular order, hoping to share with anyone wishing to learn more about audio--or even the audio engineer themselves--to procure these books. Each text will work its magic slowly because audio engineering is a multi-disciplinary field, much in the same manner as neuroscience or linguistics. While some of the books are new, others are not. But do not let that bother you too much; they all have place in the personal library of anyone who manipulates or routes audio signals, respectively.

The Recording Studio Handbook
by John M. Woram

Image source: ebay.com

During downtime on an early morning recording session, my mentor mentioned to me how and why transformers work and how and why transformers have such an effect on audio signals. I had no idea what he was talking about; I'm sure he noticed as much given the confused look on my face. After all, I was mostly there to take out the trash and clean out beer bottles. Any involvement I had in the recording process was merely due to his fatigue. He later suggested that I pick up a copy of the Recording Studio Handbook, by John M. Woram. Little did I know at the time of his suggestion that I would find myself hunched over a library desk, calculating decibels with logarithmic functions and learning about the analog world of studio recording. I'm certainly glad I took his advice. After purchasing the book and using it as both a reference source and a mental pleasure source, it has become one of the two go-to hardcover books that have contributed to my growth as an audio engineer and audio producer. Ebay had a sale listing for a 1st edition, so I paid the $45 to make it mine. If you can find an available book, you should do so, too! But caution: the book is incredibly dense, loaded with signal flow diagrams which may be quite alien to a modern, DAW-based audio engineer or producer. That learning curve can be surmounted by taking realistic time to slowly absorb the content. It's interesting to consider just how far we have come, in such little time, from, for example, editing audio with magnetic tape and a razor blade and scotch tape to firing up Pro Tools and getting the job done in a fraction of the time.

Understanding Audio
by Daniel M. Thompson

Image Source: Amazon.Com

This book is a perfect text for anyone already working in the audio industry or anyone who is looking to get a more academic approach to audio engineering. In fact, from what I know, this book has been listed as a classroom text at the Berklee College of Music in Boston, Massachusetts. It is a dense and challenging book, which aims to educate the reader on everything from signal flow to inputs and outputs to digital audio workstations to microphone placement to compression and equalization. It even addresses the more esoteric concepts surrounding the involvement of voltage and physics and how they routinely work in tandem with audio signals. I'll tell you this now: you will need to read this book slowly and with much of the patience that would be necessary with reading the Recording Studio Handbook. There is a good chance that a highlighter may come in handy; additionally, a sharp pencil will become your best friend. I read this book when I have significant downtime or when I prefer to seek reference material on audio topics. When, for example, I wanted to answer a question on the difference between impedance and resistance, Mr. Thompson shines, as he, with the employment of drawings and diagrams, expounds the critically definitional differences between the two. Now I can add value and participate in conversations with electricians and car audio professionals when they mention the importance of avoiding ground loops and why cheap electrical cables are a major no-no. All in all, Understanding Audio has been extremely helpful for me by removing my intellectual insecurity on a litany of audio concepts, and I feel that it can do the same for you.

Yamaha Sound Reinforcement Manual
by Gary Davis and Ralph Jones

Image Source: Reverb.Com

You should think of this book like an audio encyclopedia more than anything else. While both dense and informative, you will quickly be able to have informed conversations with old guard analog audio engineers, who were getting gigs and progressing the profession long before digital audio was a thing. I am not sure how the authors Gary Davis and Ralph Jones decided to organize the content, but it really covers so so many topics in audio, in physics, and even in mathematics. Again--it helps to think of the text as that ONE massive reference tool that can both answer your questions and force you to create new questions. You get everything from intensely in-depth signal flow diagrams to strict definitions of popular terms in audio to the intersection of audio and electrical engineering. I purchased the book after it was suggested to me, again, by my mentor. However, the book came in handy during my brief tenure in live sound audio. The topic needing quick absorption was gain and how to gainstage microphones for live events--from concerts to conferences. Every once in a while, I use the book to test the knowledge of other engineers and to get their insights on what works for them in real-world situations. When I have had a hard time sleeping, I have used this book to help me count sheep. I don't mean that in a pejorative sense; rather, it is meant to convey just how enjoyable of a read this book remains in my life. I am confident that you, too, will find it so.

Assistant Studio Engineer Handbook
by Tim Crich

Image Source: Amazon.Com

I was taking a smoke break when my mentor asked me if I like to read when I'm not playing around in Logic and Pro Tools. I told him I do like to read, but why does he ask. He mentioned the Yamaha Reinforcement Handbook...and then he recommended the Assistant Engineers Handbook by Tim Crich. After handing me the red covered softcover book, I read the book on my downtime during the recording sessions we would have during the next eight months. I had to decide which book would get my attention; however, I decided to stick with the Handbook. I thought it would give me a better idea of what was expected of me more quickly than the Yamaha text. I was right. This handbook, even though it addresses engineering from the analog side of the fence, explains how to conduct oneself and add the most value as a helpmeet during the quickly moving process of audio recording. Remember that plans change, songs change, gear selection change--all these elements are evolving in the studio. The chief engineer is responsible for making sure everything is sorted for the client, but you, as the assistant, are in charge of keeping clear the brain of the chief engineer. I still think assistant engineers are moving around more than the chiefs, but the chiefs are where they are because, at some point, they were also an assistant. They had to take their lumps; they had to make their mistakes and get chewed out. No one is immune from the recording process. You will learn how to manage a patchbay, how to communicate with the clients, and how to complete a recall sheet. You won't forget any of these skills either--because your next job might depend on it. And even if you are these days, like I, more of a DAW-based engineer. I believe it is critical to understand how things were done before the convenience of technology. One read through this book will give you an insider's look into the madness which was commonplace for analog recording assistant engineers.

Mixing Audio
by Roey Izhaki

Image Source: Amazon.Com

Shortly after I completed building my MIDI-based studio, I started the process of learning how to mixdown all the music I produced. This was, of course, after I heard how terrible everything sounded by overcompressing and overequalizing just about every track in each session! Mixing Audio, by Roey Izhaki, is THE book for beginners and intermediate mixing engineers. Not only does he cover the logic behind the mixing process, but he also defines each and every signal processing tool needed to take a record to the next the level--by doing less not more. Loaded with illustrations, the text is easy to follow. Additionally, Mr. Izhaki provides a CD-Rom with audio samples undergoing the signal processing techniques that are discussed in the book. I can attest this book will provide any reader with the mindset needed to approach any mixing session without confusion or fear. Personally I found the diagrams and discussions about frequency ranges of popular instruments very engaging; I even copied the section and carried it around during the day. This was to test myself so I would have a strong memory of what to listen for when listening to music or writing my own.

Critical Listening
by F.Alton Everest

Image Source: Amazon.Com

Most of the books in this blog are very scientific in their approach to many popular topics of audio engineering. This book by F. Alton Everest called Critical Listening Skills for Audio Professionals is no exception; however, it replaces the scientific rigor with importance on our hearing. I am sure we all get sidetracked with DAW updates, microphone sales, and the latest plug-ins. But our ears are the most important link in the audio chain, and we would be remiss not to sharpen this very important tool. After all, how can we hear the difference in the gear if our ears are not as sharp as they should. This book has several chapters of in-depth critical listening lessons, aimed to inform the listener as to how to identify everything from frequency to distortion to phase shifts. I do not believe it is helpful to rush through the book just to get through it. Rather, I recommend that you, again, slowly digest the lessons in the book. It will serve you better to grow with it because many of the sounds we are accustomed to hearing are closely examined here.

Acoustic Design for the Home Studio
by Mitch Gallagher

image source: B & H PhotoVideo

Most of us are recording at home, in some room, perhaps a basement or a bedroom. Years ago, when analog audio was all that existed, these rooms would have been quickly shunned as appropriate recording spaces. As time moved on and pro audio gear became more mobile, more modular, and more affordable, simply pressing a button was the only limitation to recording audio. But another problem needed to be addressed: room acoustics. Yes, we could press a button and record anything at any time. But the recordings did not sound professional, as they were severely hampered by comb filtering, phase issues, and other acoustic anomalies. Books like Acoustic Design for the Home Studio by Mitch Gallagher one of the best resources for any recordist working in less than ideal spaces. All those inherent problems with reflections, comb filtering, nodes, and antinodes are addressed in the text. In fact, with the sagacious suggestions laid out in this book, anyone can turn a room into a decent space for decent audio work. I have used this book for the last ten years. When I decided to build a DAW-based recording space in my basement, this book was tremendously helpful. (Note: Ethan Winer has also been wicked helpful, too.)

In closing

There you have it. The books that I would recommend any audio engineer read to enhance their knowledge for work in the field, I imagine that many of you already own or have heard of some of these texts. If so, good on you. But if you have not, do yourself a favor and get the books. Read the books. Struggle with the books. Keep coming back to them. With so much misinformation in the digital age, it will not hurt to have solid knowledge to guide you as you move forward in your quest to do the best you can with what you have.

]]><![CDATA[8 Important Computer Components for Recording Audio in 2020]]>Thu, 05 Mar 2020 08:00:00 GMThttps://www.counterpointsoundworx.com/blog/digital-audio-recording-2020

8 Important Computer Components for Recording Audio in 2020

You are ready to share your original ideas with the world, and you want to do so by recording a podcast. Hell yeah! But first let's talk about the heart of the technical side of the operation. The computer you decide to purchase for your podcasting is extremely important. It will be the first line of defense when combating potential audio problems; additionally, it will be the hub of all archives and other file organization. Your computer will also be the centerpiece of future upgrades. So it only makes sense that we talk for a while about how to choose a computer, including the following considerations:

1.   Processor Quantity
2.   Processor Speed
3.   RAM total
4.   RAM speed
5.   USB or Firewire I/O (inputs/outputs)
6.   Hard Drive Speed
7.   Hard Drive Volume
8.   Operating System

Since we are specifically talking about the computing environment for podcasts, we will keep our discussion relevant to a computer that is essential for recording audio, potentially editing and mixing audio, and audio file archiving. Yes, you can surf the web, word process, and even send e-mail. All those functions should be strictly limited to podcasting--because this computer will be our podcast machine. Let's get into it.

Processor Quantity

Processor quantity of the computer will determine how many calculations the computer can execute from all the applications that are open during use. Some CPU-intensive audio software programs can really put a strain on the processors, potentially causing freezes and other software issues. In fact, as audio software becomes more and more advanced, with more and more features, the software packages are becoming larger and more CPU intensive. The very last thing we want to have is a situation where the computer cannot handle the demands of recording audio. To help us avoid any of these problems, we can aim for a computer with 2 or 4 cores. If you can find a good deal on a computer from the list with more cores than this; by all means, go for it and make the purchase. Several brains should be enough to handle all the audio software, all the post-production software, and any other creative software that you may choose to integrate into your podcast or voice talent projects. If you are ambitious, you can even upgrade the cores to faster cores, in some of the computer models. Information concerning these types of upgrades can be found on YouTube.

Processor Speeds

Processor speeds, or core speeds, are measured in gigahertz (GHz). Many years ago, in the early days of computing, processor speeds were measured in MHz, or megahertz. In 2020, there is no real reason why we should be considering a computer with processor speeds in the MHz. These days, any processor at or above 2GHz is a good start. Remember that you will more than likely purchase a computer with more than one processor, so you may have a machine with, for example, two or four 2GHz processors. If we follow protocol and only use the machine for audio recording, and other functions related to audio recording, that means we have multiple cores to assist us in the recording projects. (Note, if you are planning to record visual data along with the audio data, you will have to check the processor specifications of the software you are planning to use.) I think a good place to start is around 2GHz, but later I will make an argument for why more cores is better than the individual speeds of the cores.

RAM Speeds

RAM speeds, (random-access memory) speeds, will affect how quickly software programs run once they are opened by the user. The faster the RAM, in theory, the faster and more efficient the software should execute tasks. Also, more technically, RAM will randomly store data concerning the software that is being chosen to run on the computer. This data is very important, as it is used to log vital statistics about the health of the software. RAM speeds are also described in relation to the type of RAM. The computer specifications will guide you as to what RAM you should buy for your computer, and to list all the types of RAM here would be outside the scope of this blog. At the time of writing this blog post, my Mac Pro houses DDR-type RAM. It gives my machine plenty of punch, and this is also the type of memory specified to be used by Apple. I believe it's more important to have as much RAM as possible than to focus on the speeds of each RAM module, as RAM can be expensive.

RAM Totals

If a machine does not have enough RAM, as discussed before concerning processor speeds, the computer may freeze, resulting in a reboot. Software will also demonstrate extremely long load times. I remember what it was like having a laptop with only 2GB and trying to write college papers while running AOL AIM. That was a nightmare. All the software on my machine took forever to load. In fact, sometimes the load times would be so long, the computer would lose track over which function to perform and it would just freeze-in-place. Imagine if you are recording an audio session and this happens? Yeah, exactly. A good place to start with RAM is between 16GB and 32GB. Most desktop computers have an upper limit of how many RAM modules can be added to the machine. If money is no issue and you want to future-proof yourself, I say go right ahead and occupy every RAM slot with the maximum. Depending on what computer you purchase, you will have to pay close attention to which type of RAM is specified for the computer. This information is usually found on the computer manufacturer website.

USB or Firewire I/O (inputs/outputs)

The hardware we need to use to record our podcast audio will either be plugged into a USB or Firewire port. Each of these ports support different speeds, and during the setup, we should read the manual to ensure proper usage. Most audio interfaces are either USB 2.0, USB 3.0, Firewire 400, or Firewire 800. I have used many that cover all the mentioned formats. Some are more expensive than others. I do not believe it is a matter of expense; rather, it should be a matter of functionality. I will touch on this later in time. But, again, when I decided to purchase my used Mac Pro, I kept in mind the number of USB ports that came with the machine. Some newer computers, such as the 2019 Mac Pro, have Thunderbolt ports. This may be out of our hands depending on which computer we purchase, but I would aim for a computer with at least 4 USB ports. Even if you run out of USB ports, you can purchase for a few dollars a USB expansion hub, which will plug into one available USB port and provide you with up to 8 more USB inputs.

Hard Drive Speed

There are also two types of hard drives now that can be used in many types of computers. One type is the standard hard drive. These hard drives often spin at three speeds: 5,400 RPM, 7,200 RPM, 10,000 RPM. RPM means Rotations Per Minute. The faster the hard drive speed, the faster files can be stored and the faster files can be recalled. The other type of the hard drive is the SSD, or the solid state drive. The solid state drive is a much faster hard drive, being known to store and recall files 5x to 20x faster than the SSD. Not all computers have motherboards to house solid state drives, so, again, it is best to consult with the manufacturer specifications in the manual. For our purposes of recording audio, we will have to recall the files and also store them. And these files can get rather large. I would aim for a drive with a speed of 7,200 or 10,000RPM. These advice also pertain to the purchase of external hard drives, which may be used for archiving recorded audio. The external drive can also be USB or Firewire, and it will available at several storage capacities.

Hard Drive Volume

While still speaking about hard drives, we can also discuss hard drive volume, which is measured in Gigabytes. The more Gigabytes we have, the larger the hard drive. The larger the drive, the more audio we can store and recall. I personally like hard drives that are at least 1T (1 Terabyte in size) because I can partition that drive into halves. One half can be for edited and mixed audio, while the other half can be for raw audio that needs post-production. Or I can keep the drive at 1T and be confident that I have plenty of space to safely store and recall recorded audio content. Another key factor to consider with regards to hard drive volume is how will the drives be used? I said earlier that I would partition a 1 terabyte into halves. Perhaps you will retain the 1 terabyte drive and only allow it to be used for recorded audio. That would be a great idea, as you would be able to create organized folders which would assist you in your archiving efforts. Perhaps you would use the drive for sound fx and interviews, both with the same archiving strategy. It would not be a bad idea to do so.

Operating System

Operating Systems are very important to this discussion because the hardware we select must be compatible with the software managing the functions of the computer. There are many choices for operating systems; however, I will only discuss the popular three: Windows, MacOSX, and Linux. Most of the computers that are available on the new and used market will run either some version of Windows or some version of OSX, but that is not to say that it is impossible to find a computer that runs on Linux. There was a time when the digital audio workstation you choose to record your audio will have to be compatible with the operating system. Luckily, these days, many DAWs are inter-operable, meaning the software

Conclusion

So there you have it...the 8 Most important Computer Components for Audio Recording in 2020. Most, if not all, of these components can be found on popular sites such as eBay, Amazon.com, and NewEgg.Com. As stated above, when upgrading your computer, always refer to the manufacturer specifications to ensure you are on the right track--and avoid potentially damaging your system. Prevention is better than cure! Also, take your time to shop around for good deals on computers that might already have the computing components that you are looking for. If it makes if makes sense for your wallet, go ahead and make the purchase. And most importantly, try your very best to get the most out of what you already have. It is very easy to get into "GIMME GIMME" mode, spend a bunch of money on things you don't need, and wind up feeling frustrated. There is nothing fun about that!

]]><![CDATA[Audacity Podcast Tutorial for 2020]]>Tue, 25 Feb 2020 08:00:00 GMThttps://www.counterpointsoundworx.com/blog/audacity-podcast-tutorial-2020

Audacity Podcast Tutorial for 2020

I am sure you are very excited about the possibility of creating genuine and unique podcasts for the web, for the classroom, and for all other listening media. Searching for the best free web recording programming can be overwhelming at first, so I recommend looking no further than Audacity. Audacity has many highlighted features that provide the novice and the expert, alike, helping them achieve good sonic quality. The result will be an informative and professional-sounding podcast.

At first glance, the user interface of Audacity might be a bit challenging, but the truth is, over time and with this tutorial, you will quickly navigate the key recording features you need to get the ball rolling. Remember to take your time, plan the content, and be aware of several key factors, such as audio levels and file archiving maintenance. Actually, when you get the hang of these key highlights, you'll be recording top notch podcasts before you know it.

This tutorial will include both text and graphical diagrams, so you can keep easily following along while you learn.

Step 1: Download Audacity from
https://www.audacityteam.org/download/

With the link above, you can select which version of Audacity you would like to download for your selected operating system. If you are using a Windows-based computer, you should select the software package for Windows. If you are using a Mac, you should select the software package for OSX. If you are using a computer that runs on Linux, also download that software package. This is very important, as if you accidentally download an incompatible software package with regards to the computer you will be using to record your audio podcast, the software will not be loadable on the computer. Taking the time to ensure that this step is correctly executed should get you moving to the rest of the tutorial.

At the time of the creation of this Audacity Podcast tutorial, the latest version of the software is 2.3.3. Also be aware that as the software platform evolves and improves over time, these steps might change. Check back here for future updates that might affect the functionality of the software.

Step 2: Configuring Audacity for Audio Recording

Once you’ve mounted Audacity on your hard drive, configuring the software for audio recording is next. When you open Audacity, go to “Edit” and “Options” features to adjust the important settings concerning the device which will be used to record the audio. This next step can be tricky, as you may not be familiar with the terminology. Go to “Devices” to edit the sound card and audio channels. Note: The audio interface (i.e. sound card) you are using to record your audio will determine how many audio channels you should select. So it is important that your audio interface or sound card is plugged into the computer, so that your computer can confirm this physical connection with Audacity.

Step 3: Audio Host Selection

To ensure the correct audio host is handling the incoming audio from the audio interface, select the appropriate option in the "Interface" section. The "audio host" is the connection between Audacity and the sound device, and you can see in the options menu "MME" may be selected already. MME is the Audacity default and the most well suited with all audio devices. If you are using a Mac, you may want to experiment with Core Audio, as this is the default for Mac OSX. You will also see "Windows Direct Sound". This selection is better than MME, as it provides an audio recording experience with potentially less latency. We can define latency as the time it takes for the audio to be captured by the software from the audio interface or sound card.

Step 4: Playback Devices Selection

Here you will select which playback device will allow you to hear the audio once it has been recorded into the software. You can experiment with the settings here, as some playback devices will offer better sound quality than others. If you are using an audio interface or sound card, and you have connected speakers, you can go ahead and select this as the playback device the audio interface or sound card that you are using. Consequently, this will mean that this device will handle all the audio recording and all the audio playback, which is pretty neat, as this will save you space in your studio! :-)

Step 5: Channel Selection

Your podcast recording does not have to be recorded in "Stereo", so you should select "Mono". Mono is short for monophonic, which means means one channel is going to be used at a time to record you audio. This would suggest you are using one microphone for each speaking participant of your podcast session. The number of speakers you showcase on your podcast will be determined by how many microphone channels are provided by your audio interface or sound card.

Step 6: Sound Selection

You will now select how loud or how quiet your microphone will get when recording into Audacity. This can also be set on the faders or knobs of the audio interface or sound card you are using. The benefit of adjusting these levels is that it creates an overall ceiling of how loud your audio will be in order to avoid distortion. Go to “Control panel > Hardware & Sound > Sound > Adjust Machine Volume.” You should keep these settings intact, as it will help you achieve an overall sound level to all incoming audio from the microphones you are using. Again, keep in mind that you can also do this by experimenting with the audio interface.

CONGRATULATIONS! If you have followed these steps, you are now ready to start recording podcast audio! The next steps will detail the audio recording process.

Step 7: Recording Audio for your Podcast

Select File > New, and you will see a new window appear on your screen. This is your recording and playback window, and on the very top of the window you will see several buttons. These buttons control essential functions of the podcast recording session. We will go over these buttons now. We can define these buttons as "Transport Buttons", and we can define this section of the record screen as the "Transport Section".

Step 8: Transport Buttons

This is the Record button. Pressing this button will allow the software to capture all the audio that is going into the microphone.

This is the Pause button. Pressing this button will result in any audio that is playing will to stop briefly in place. This function is best used when inspecting recorded audio for errors.

This is the Loop button. Pressing this button will result in any audio that has been selected with the cursor playing back in a loop until you stop the audio by hitting the Stop button. To activate the loop function you must press Shift.

This is the Play button. Pressing this button will result in any audio that has been recorded in your podcast session why playing until the completion of the session. You will be able to hear the recorded audio through your speakers or headphones.

This is the Stop button. Any audio that is playing from the podcast session will stop.

This is the Rewind button. Pressing this button will result in the audio going to backwards. You can, with the cursor, determine at what point in the audio the rewind will stop.

This is the Fast-Forward button. Pressing this button will result in the audio going forwards. You can, with the cursor, determine at what in the audio the fast forward will stop.

Step 9: Importing Audio to your Podcast Session

There may be a time when you would like to add previously recorded audio to your current podcast session. This is very easy to do. In the File section of the software, select Import then Audio.

After you have selected Audio, the window below will appear. Here you can add as many audio files you would like. The audio files will occupy their own track in the main software window.

Remember that after you select the audio you would like to add to the podcast session, each audio file will create a new track. These new tracks can also be adjusted for levels.

Step 10: Saving the Podcast Session

There is a funny-but-wise saying that goes something like this: Always be Saving! You never know what can happen during or after a podcast recording session. Maybe the computer will give out and freeze. Maybe the software will stall and cause errors in the recording. Maybe the power will be interrupted. You never know. So it's important to always save the recording. We can do by going to File > Save. Then you can provide an appropriate name for podcast session.

Conclusion

This provides and outline to get anyone going on the Audacity software for podcast audio recording. It is important to follow the steps initially, so that over time, you will be able to master the essential function of audio recording. If you have any questions, do not hesitate to reach out to Chris.Ray@CounterpointSoundWorx.Com for advice and tips.

]]>

7 Books for DAW-based Audio Engineers in 2020

Introduction

The Recording Studio Handbook​by John M. Woram

Understanding Audio​ by Daniel M. Thompson

​Yamaha Sound Reinforcement Manual ​by Gary Davis and Ralph Jones

​Assistant Studio Engineer Handbook ​by Tim Crich

​Mixing Audio ​by Roey Izhaki

Critical Listening ​by F.Alton Everest

Acoustic Design for the Home Studio​ by Mitch Gallagher

In closing

8 Important Computer Components for Recording Audio in 2020

Audacity Podcast Tutorial for 2020

The Recording Studio Handbook
by John M. Woram

Understanding Audio
by Daniel M. Thompson

Yamaha Sound Reinforcement Manual
by Gary Davis and Ralph Jones

Assistant Studio Engineer Handbook
by Tim Crich

Mixing Audio
by Roey Izhaki

Critical Listening
by F.Alton Everest

Acoustic Design for the Home Studio
by Mitch Gallagher