Guitar frequency question

[helpmeout]

Hi Mixerman,

I've got a question about the frequency range of a guitar's 'sweet' spot.

I want to preface this question so I can explain why I'm asking it. I've been wearing hearing assistance devices since I was a child. This did not stop a love of music nor the desire to play guitar.

I took delivery of an all digital hearing system on Wednesday. These are Phonak's Savia™ 311dz hearing aids, supposedly their flagship model. So far, I've been totally underwhelmed by them. My biggest complaints, aside from how much incredibly nasal they make my voice sound, is how scooped everything sounds. In spite of increasied pickup of background rumble, everything else sounds far away and muffled. To put it in a visual analogy, it is like trying to see through a pane of glass that was wiped with a greasy towel.

These all-digital devices are said to have a frequency response of 100-6800 Hz, with 20 bands of adjustability. My old hearing aids were ADD, to date, they've been the best aids in my never-ending search for musical enjoyment. Alas, they are 10+ years old, and failing. The usual life expectancy is 3-5 years, but I've been told I take pretty good care of them.

I've had the great fortune of excellent tutelage in what makes for a good guitar sound through hanging out with some gifted guitar players. I know what sounds good, and what doesn't. These new hearing aids DO NOT SOUND GOOD, as they are currently set. Right now, the new ones clip horribly at any transient sounds, and particularly with pick attack. God, there is this horrible click whenever I hit a string. Talk about digital clipping. Blargh. Digital feedback sounds like an alien movie sound effect, like evil skilsaws floating around looking for heads and limbs to sever.

To make a long story short (oops, too late), what frequency points can I direct my audiologist to work with to get the 'sweet meat' of the guitar working on these infernal devices? I'm beginning to think digital was not the way to go, after all, especially upon perusing comments on this and other recording/audio related forum regarding digital vs analog.

I'm going in Monday morning to see my audiologist to try to tweak these things. Any help would be greatly appreciated.

[Mixerman]

Hi Mixerman,

I've got a question about the frequency range of a guitar's 'sweet' spot.

I want to preface this question so I can explain why I'm asking it. I've been wearing hearing assistance devices since I was a child. This did not stop a love of music nor the desire to play guitar.

I took delivery of an all digital hearing system on Wednesday. These are Phonak's Savia™ 311dz hearing aids, supposedly their flagship model. So far, I've been totally underwhelmed by them. My biggest complaints, aside from how much incredibly nasal they make my voice sound, is how scooped everything sounds. In spite of increasied pickup of background rumble, everything else sounds far away and muffled. To put it in a visual analogy, it is like trying to see through a pane of glass that was wiped with a greasy towel.

These all-digital devices are said to have a frequency response of 100-6800 Hz, with 20 bands of adjustability. My old hearing aids were ADD, to date, they've been the best aids in my never-ending search for musical enjoyment. Alas, they are 10+ years old, and failing. The usual life expectancy is 3-5 years, but I've been told I take pretty good care of them.

I've had the great fortune of excellent tutelage in what makes for a good guitar sound through hanging out with some gifted guitar players. I know what sounds good, and what doesn't. These new hearing aids DO NOT SOUND GOOD, as they are currently set. Right now, the new ones clip horribly at any transient sounds, and particularly with pick attack. God, there is this horrible click whenever I hit a string. Talk about digital clipping. Blargh. Digital feedback sounds like an alien movie sound effect, like evil skilsaws floating around looking for heads and limbs to sever.

To make a long story short (oops, too late), what frequency points can I direct my audiologist to work with to get the 'sweet meat' of the guitar working on these infernal devices? I'm beginning to think digital was not the way to go, after all, especially upon perusing comments on this and other recording/audio related forum regarding digital vs analog.

I'm going in Monday morning to see my audiologist to try to tweak these things. Any help would be greatly appreciated.

Wow. This is a tough one.

On the one hand, you're telling me that the new aids increase background rumble and make things sound nasal. A "nasal" sound, to me, has an excess of frequencies between 400 and 700hz. And the "rumble" would be down around the 100hz range. I can only base these assesments on the adjectives you've provided and what they mean to me.

Personall, I think your clipping issue is your biggest one. Obviously, you're getting too much input. You would think that they'd put a brick wall limiter on a hearing aid to prevent that. That could be a ridiculous notion for all I know, because I don't know how small you can make a limiter like that. But if you're clipping, the input is set too high. But if you set the input too low, then you might have trouble hearing normal conversation. Without a limiter, transients are going to clip.

The peak of human hearing is somewhere around 2k. I would imagine this is where the predominant boost is for your hearing aid. But your adjective of nasal makes me wonder if maybe the boost is more towards 1k or even lower. But then you say you're missing the "sweet meat" of the guitar, I'm further confused.

Further making this difficult, is not knowing how broad the bandwidth is on the EQ of this device. You know, if there is a wide Q on the 6800hz EQ, then shit, boost that one. Unfortuantely, I would suspect that there are a series of notched EQs. So, I'm afraid I'm shooting in the dark here.

After all that, I'm going to give you the best advice I can think of, and I just thought of it. Bring your guitar to your audiologist (and amp if you are using one), and have him make the adjustments for you based on that. You might have to ultimately come to a compromise down the line, somewhere in the middle. Or maybe have one for when you play guitar, and one for your day to day living. The fuckers could cost $50,000 for all I know and that would quite obvisously be prohibitive.

I'll watch to see if you have any replies to see if we can further hone in on the frequencies necessary.

And hey, anyone else reading this don't be bashful. If you've got ideas put them up. The guy has an appointment in about 60 hours.

Mixerman

[blackieC]

Man, I'm just not sure where to go with this. When you talk abou the "sweet meat" of the guitar I'm not sure exactly what you mean by it. Like Mixerman I leap to 100k for the rumble aspect, but who's to tell where the meat is that you're hearing. Your previous devices might have had a curve that placed the 300k range that a lot of us cut as "mud" as the beauty part of the sound.

Would it be practical to try different brands or models of devices?

I apologize for my ignorance in that arena but any other info you can give us would go a long way towards being of assistance.

Like Mixie said, the clipping and probably the rumble have got to be the result of excess gain. Is the gain of these devices as flexible as the EQ? More importantly can the limiting be tweaked?
Something also makes me suspect that the nasal quality of your own voice may be a result of the devices amplifying contact soundwaves through your own body. Again, a gain issue.

It's probably apples and oranges, actually it's in the completely opposite direction, but in the past I have used shooting ear protection that allowed conversation to be heard at normal levels and yet was quick enough to yank the brutal transient of a .357 magnum down to the same level without a glitch. The ignorant optimist in me has got to believe that similar abilities are available in a smaller package

[Thumper]

Another thing to check...

About YOUR voice sounding nasal... Do other people's voices sound like that as well? If not, and it's just you, then you might just have a nasaly voice!!! HA!!! I kid I kid... But seriously... If other peoples voices sound right, but yours doesn't, I'd check to make sure that you had good ear impressions done, and that the fit of the hearing aids is right. If there's a little leak of air, it can do really weird things to your own voice.

[helpmeout]

Another thing to check...

About YOUR voice sounding nasal... Do other people's voices sound like that as well? If not, and it's just you, then you might just have a nasaly voice!!! HA!!! I kid I kid... But seriously... If other peoples voices sound right, but yours doesn't, I'd check to make sure that you had good ear impressions done, and that the fit of the hearing aids is right. If there's a little leak of air, it can do really weird things to your own voice.

I am well aware of how nasally my voice is, I've heard it on tape before. Who the hell is that? LOL. 'tis a fine New England nasality, it is. I've heard Mixerman's voice on his radio show, it is a lot like that.

I've swapped the ear molds (don't worry, its not a disease or anything like that) and tubes from the new hearing aids to the old ones, and vice versa. So far, the acoustic performance is the same. The old ones are only a couple of years old, so they were practically identical. I feel confident that variable has now been eliminated. Thanks, Thumper, that was a good idea.

[Brendo]

It sounds to me like you paid good money for these Phonak devices - you describe them as top of the line.

However you say your old ADD's were better.

Is it too late to return the Phonak's and look into what ADD have to offer in a new aid? From your last experiment, it seems that the ear molds and tubes are not the issue.

If you're stuck with the Phonak's, ask your audiologist if there is a limiter that can be turned on. Also can you listen while he tweaks stuff? Take along a CD that you know the sound of and throw that on while he tweaks, so you can get it sounding right.

[Mixerman]

I am well aware of how nasally my voice is, I've heard it on tape before. Who the hell is that? LOL. 'tis a fine New England nasality, it is. I've heard Mixerman's voice on his radio show, it is a lot like that.

I've swapped the ear molds (don't worry, its not a disease or anything like that) and tubes from the new hearing aids to the old ones, and vice versa. So far, the acoustic performance is the same. The old ones are only a couple of years old, so they were practically identical. I feel confident that variable has now been eliminated. Thanks, Thumper, that was a good idea.

Okay, okay, okay, yeah, yeah, yeah. Good idea thumper...

But are you going to bring your guitar and amp to your audiologist appointment on Monday?????

Mixerman

[Bob Olhsson]

Towards the end of her life my mother needed hearing aids. I was utterly shocked by the low quality of what was available at astronomical prices. I got her a simple mike and headphones from Radio Shack and she thought it sounded worlds better than her $1000 hearing aids.

[otek]

I don't claim to be an expert, and for all I know, this may be a question of system calibration.

I do know however, that hearing aids is something you need to get used to over time. If you got them on Wednesday, you haven't been wearing them for too long, and everyone I know with hearing disabilities have told me that it takes weeks to adjust to a system.

Sorry if this is a naive observation on my part as you probably know loads more about this topic than I do.

[helpmeout]

It sounds to me like you paid good money for these Phonak devices - you describe them as top of the line.

However you say your old ADD's were better.

Is it too late to return the Phonak's and look into what ADD have to offer in a new aid? From your last experiment, it seems that the ear molds and tubes are not the issue.

If you're stuck with the Phonak's, ask your audiologist if there is a limiter that can be turned on. Also can you listen while he tweaks stuff? Take along a CD that you know the sound of and throw that on while he tweaks, so you can get it sounding right.

Fortunately, I have 30 days to decide on whether or not to keep them, sort of like GC. There are systems similar to my old ones, and I'll be seriously looking at them if I can't tweak these.

I like the idea of taking a CD I'm familiar with.

There is some sort of compressor mentioned in the audio data, claims an attack of 1ms and recovery of 10 ms. This may be their idea of a limiter, I'll have to find out if it is adjustable or not.

[helpmeout]

Okay, okay, okay, yeah, yeah, yeah. Good idea thumper...

But are you going to bring your guitar and amp to your audiologist appointment on Monday?????

Mixerman

Yes, I'm going to bring my guitar and amp. They don't know it yet. Would be cool if some one is in the waiting room when I carry that in, I wonder what kind of looks I'll get :)

[helpmeout]

hm, 2.5% THD at 500 Hz, 1.5% THD at 800 Hz, and 1.0% THD at 1600 Hz.

I'm not an engineer, but compared to hi-fi gear in the past, that seems like a lot of distortion for what is supposed to be high-end audio gear. Maybe somebody could enlighten me to total harmonic distortion and how it applies to listening?

[Brendo]

Yes, I'm going to bring my guitar and amp. They don't know it yet. Would be cool if some one is in the waiting room when I carry that in, I wonder what kind of looks I'll get :)

Take some earplugs for the audiologist as well... although I'm sure he'll have his own, it'd be a nice gesture :lol:

[FajitaTone]

THD's usually are below 1.0% for good gear, no?


:Uh oh:

[volthause]

Way below... Like in the .08% area for consumer audio.

[Thumper]

THD is usually only used for electronics specs... Not speaker specs. Speakers inherently have horrible THD specs. That's just the way they work.

Hearing aids have speakers in them, so if the THD was measured after the speaker, I wouldn't worry about it. Actually, those specs are quite good.

If it was measured post electronics, but pre speaker, then those specs are pretty horrible...

Hows the status on our thread starter? Any good news?

[archtop]

I would also get to graphic E.Q. and start, at the bottom and peg, and then cut, and move your way up to get an idea how
their curve is, what works and what doesn't.

[Mixerpuppet]

I would also get to graphic E.Q. and start, at the bottom and peg, and then cut, and move your way up to get an idea how
their curve is, what works and what doesn't.

I did this not too long ago with a customer involving a lawsuit against the Gov. The standardized Audiologist tests and equipment are not what you'd expect. I simply took a normal voice sample and used a parametric eq and tweaked after some basic questions about what hearing he had left.

The self noise of the human ear is pretty aweful once all the masking element have been diminished via some malfunction.

A pair of Paragraphic eq's, headphone amp and good headphones are alot more capable than your average hearing crutch peddled by insurance companies.

I generated some curves of what we swept on the eq's verses the selective frequency check points...

.5, 1 ,2, 3 ,4 and 6Khz for OSHA and MSHA

But its usually up to the discretion of the Physician....

Like I expected his best hearing fell in between the cracks so the devices were completely worthless.

I started with these...
test range 0.25, 0.5, 1, 2, 3, 4, 6, and 8 kHz and in the range 9, 10, 11.2, 12.5, 14, 16, 18, and 20 kHz

I also recorded what frequencies that could be cut to improve things.. 9db cut at 490Hz.

I'll be doing the same for my daughter who had one too many burst eardrums from ear infections...

I have headphone pattern baldness...:Sad:

[Mixerman]

Hey, helpme out!

What happened?

Help us out!

Mixerman

[helpmeout]

I walked in with a guitar and an amp, there was an elderly couple waiting there. I just smiled at them, and said 'hi', and greeted the receptionist like I did this all the time.

Unfortunately, the appointment was only scheduled for 15 minutes, so I didn't get to use my guitar. I also brought my Rolling Stones "Sticky Fingers" cd, but no speakers on the audiologist's laptop :Sad:

Anyhoo, I brought up the transient clipping. She said 'the power section is not loud enough'. Huh? I would have thought the input gain was too high, thus overloading the power section. But sure enough, most of it got cleared up by boosting the power section. Re: the nasality, what seemed to work there was boosting some lower mids. I'm getting less of the 'everything is distant' effect. The low end was also dropped a little, reducing the rumble. I asked about the kneepoints of the compressor, and was told it was the same as my old hearing aids. This blew my mind, as I never even noticed it working on them.

I asked about the 20 bands of adjustability, and found out each of them have their own compressor, and are individually programmable.

My voice sounds much closer to what I used to hear, both in terms of tone and proximity. More tweaking still needs to be done, and I've got another appointment next week, for a whole hour, and I was told to bring the guitar!

Last night, I noticed an interesting effect. I was playing my guitar unplugged in front of my computer. When I hit a note, the sound picked up by the hearing aid would bloom, let in more background noise (computer fan) and then fade out, even if the note on the guitar string wasn't done resonating. It was like it was breathing, or pumping in response to the attack on the guitar string.

I'm still getting some clipping when I play plugged in, although it is now at least when I actually play forte and have the volume on the guitar wide open. I've gotten quite a bit of the 'sweet' back, but a whole lot more sibilant highs than I used to get. Granted, it IS a Stratocaster, which is a snappy guitar to begin with, albeit with a rosewood fingerboard.

I need to visit my buddy's guitar shop and listen to some of his les pauls through marshalls, for some comparision between both sets of hearing aids.

thanks to everybody for the suggestions and ideas. It is really appreciated.

[helpmeout]

cool, I just checked my email, and here are the frequency points of the bands.

140 h
320
480
640
800
960
1.1k
1,3
1.5
1.8
2.2
2.5
2.9
3.4
3.9
4.6
5.5
6.6
7.9
9.5

[Grapestomper]

Million dollar idea:

Bluetooth hearing aids, alowing you to load a preset from your laptop.



You could have presets for

Stage Volume.

Quiet Conversation.

Door-to door Salesperson.

Whatever!

M

[helpmeout]

Million dollar idea:
Bluetooth hearing aids, alowing you to load a preset from your laptop.
You could have presets for
Stage Volume.
Quiet Conversation.
Door-to door Salesperson.
Whatever!
M

Well, they actually have Bluetooth for hearing aids. I pitched an idea to the H.E.A.R. people at the AES in NYC about something like that, and added in a mic farm idea, that you could listen to something and say "hm, what would that sound like with a U47? A C12? RE 20? SM 57?" All I got was a blank stare. Guess they were not quite hip to studio stuff.

[Tim Halligan]

Million dollar idea:

Bluetooth hearing aids, alowing you to load a preset from your laptop.



You could have presets for

Stage Volume.

Quiet Conversation.

Door-to door Salesperson.

Whatever!

M


My mother was given a brochure a few years back when it was time to update her hearing aid, and this concept exists in a slightly different form already.

Digital hearing aid - specifically designed for users who require one for each ear (my mother is a candidate) - with a remote control like your TV with a series of presets and a volume knob, for situations like a cocktail party/reverberant environment, quiet conversation, watching tv, and exterior environment.

The cost was in the order of $10000 Ozbucks...so Mum passed on them.


Cheers,
Tim

[Bob Olhsson]

The key to decent sound is getting the microphone out of the ear piece. Until you do that, feedback suppression processing is going to kill your sound quality exactly as it has in too many sound systems.

[helpmeout]

Digital hearing aid...with a remote control like your TV with a series of presets and a volume knob, for situations like a cocktail party/reverberant environment, quiet conversation, watching tv, and exterior environment.

Actually, I'm on my second system with a remote. However, this one has the full digital signal path, and a lot more processing.

The key to decent sound is getting the microphone out of the ear piece. Until you do that, feedback suppression processing is going to kill your sound quality exactly as it has in too many sound systems.

what about microphones on the behind the ear (BHE) unit? I had one set, years ago, that were CIE (complete in ear). I think I went 10 years without smiling, er, unsuccessfully I might add. I got feedback when I smiled, like when I saw a pretty girl. It got to the point when my friends would call it my 'hornpout' alarm. 'Eeeee-eeeeee' "Uh-oh, he's looking at a pretty girl again, horny alert, hornpout alert". Damn, that used to be soooo embarassing.

[helpmeout]

my audi is letting me work with the hearing aids. I was told that the federal government and OSHA are behind the requirements of the noise suppression (compression circuit) levels.

We've done some tweaking. Coffee cups on the counter no longer clip (as often) the output. A handclap, my voice when I raise it (I'm a loud fucker), and my electric guitar will cause it to clip, though. This is fucking crazy. I need those transients, I can't have the hearing aids dropping the sound out on me for a momentary overage on an (in my opinion) arbitrary decibel level. God help me, I haven't seen a loud band yet with these things.

As far as the sound of the guitar goes, I'm getting more of the sweetness back, and a lot more twang than I used to get. Being that it IS a strat, I suppose that is not too unusual.

Still not sure what to do. These new hearing aids do have fabulous high end articulation, and excellent bass response (go figure, digital and all). If I could just get rid of that goddam clipping, fucking feds. I really do not want to go through the hassle of having two sets, one for guitar, one for everything else.

[Brendo]

what ones would you use for guitar if you did happen to decide to go for two sets?