Tuning/Intonation Errors Options

[bassrun]

Based upon my own positive experience with the StroboFlip as well as the enthusiastic reviews that I read at the iTunes app store--but in spite of some conflicting reports on the Unofficial Martin Guitar Forum (www.theunofficialmartinguitarforum.yuku.com)--I purchased and installed iStroboSoft. Unfortunately, I'm experiencing the same problem that I read about on the UMGF.

Specifically, when I carefully tune each string with iStroboSoft, the result is a poorly tuned guitar. On the other hand, using either a standard electronic tuner or the free iPhone app "Tuner," the result is a perfectly tuned guitar. The problem is with the 4th and 6th (D and low E) strings--the other 4 strings are tuned properly by iStroboSoft.

Anecdotal reports on the UMGF (http://theunofficialmartinguitarforum.yuku.com/topic/83559/master/1/?page=2) indicate that this intonation problem can be cured by subsequent installation of Guitar ToolKit. But I sure as heck don't want to pay $10 for GTK just to fix iStroboSoft.

Are you aware of this problem? Has anyone discovered a no-cost fix?

--John

[Marshall Johns]

John,

Thank you for your contact.

Are you using the Peterson adaptor cable or the built-in mic? Is this an iPhone 3G or 3Gs? iPod?

The installation of GTK does not seem to be a valid remedy for this. Installing one app to fix another does not make sense aside from the fact that it may prompt for a rebooting of the device. Rebooting the device after installation of iStroboSoft is recommended and explained in the App Store description. This may be the fix for other users if they did not originally power cycle their devices.

If your device is a 3Gs, this may be the issue. We have recently identified that the 3Gs adds a high-pass filter on the built-in mic that carries over to the line/mic-in connector. The filter is set steeper than on the 3G at approximately 250Hz. The strings you mentioned are located under this frequency and may be problematic to tune.

The noise filter and boost may improve your readings. If you are using an adaptor cable, plug in the adaptor cable WITHOUT plugging in your guitar or mic, run the noise filter, then connect your instrument/mic.

For 3Gs users, we are looking to address the issue of the high-pass filter, as many other audio measurement applications are at this time, and will release an update when possible.

[bassrun]

Marshall--

Thanks for your reply. I just left you a phone message, not realizing that you'd already replied to me online.

I'm using a 3Gs without an adapter cable--just the built-in mic. And yes, I agree that installation of GTK sounds like a dubious remedy!

When you recommend rebooting, you're just talking about powering off the iPhone, or is there some other more fundamental rebooting routine? I did power off my iPhone, and it didn't help. I also tried toggling both the noise filter and the boost setting, but with no effect.

Interestingly, the free iPhone app "Trace Tuner" (which is not nearly as sophisticated as iStroboSoft) registers the pitch of my strings perfectly, so I'm surprised that iStroboSoft would have problems with the high-pass filter. If the problem is with the iPhone's built-in mic, does this really make sense?

Is there any thing special about the Peterson adapter cable? Is it anything more than a 1/4" to 1/8" adapter?

--John

[sabecker]

After installing iStroboSoft on my iPhone 4 and restarting the phone, I find that it consistently cannot properly tune the D string. The app indicates that the D string is approximately 6 cents flat when it is perfectly in tune. It can tune correctly if I play the harmonic at the 12th fret on the D string (or higher harmonics). At least one other tuner on my iPhone works perfectly well with the D string. A brief internet search reveals that this has been a problem since the iPhone 3GS.

I am using the iPhone's internal microphone.

Is there any resolution to this issue either available or planned?

[Marshall Johns]

Hello sabecker,

Thanks for your post.

Briefly:
Is this app calibrated to an external source to guarantee 1/10th tuning resolution?
Electric or acoustic? Guitar or bass?
How old are the strings?
Same results when using the +24dB boost?
Noise filter on and, if so, were the requirements during profiling observed?
When tuning open D and it is showing 6 cents flat, is the correct octave shown?

Using other tuners may not always yield a one-to-one result as they cannot offer the same accuracy. With accuracy windows of +/- 2-3 cents, they may show you that you are in tune when you are clearly not.

Regarding the 3GS, the built-in mic employs a steep high-pass filter around 150Hz to optimize voice quality. The D string (D3) is located at 146.83Hz. This is approximately where the roll-off starts. We have not heard of any issues with iPhone 4 users until now so until I can assume the same filter is included on the built-in mic.

The harmonic (D4) is closer to 293Hz so it is far past the cut-off point and thus yields a better tuning result.

Boosting the input gain and increasing tone controls will also increase the amount of noise coming in so it is best to apply limited amounts at first until a successful measurement is observed.

[ukbrewer]

Ok so here's my problem. When tuning E2 the Istrobosoft displays E3

I've checked with my B**$ tu-15, polytune iPhone app and strobisoft on my iMac. All show the low E being in tune.

Using the following
iPhone 4 with OS4.1
Istrobosoft 1.30.02
Peterson Direct Input Cable
Musicman Axis Super Sport
Freshly opened GHS Boomers GBXL

Anyone else having this issue?

Love the app with the exception of this issue.

Thanks.

[Marshall Johns]

ukbrewer,

Does using the noise filter make a difference? Is it on or off when you experience this?

MJ

[ukbrewer]

ukbrewer,

Does using the noise filter make a difference? Is it on or off when you experience this?

MJ

Connecting with your cable adapter, I shouldn't need the noise filter, correct? and yes same issue

[stfuppercut]

For 3Gs users, we are looking to address the issue of the high-pass filter, as many other audio measurement applications are at this time, and will release an update when possible.

has a patch been released yet that addresses this? i don't see it on the version history and would like to know before i buy the app

[Scott Helmke]

I've got the exact same problem - D on a guitar reads about 6 cents flat.

iPod Touch 4, with the latest software.

I can use the octave harmonic and it's dead on accurate. Fretting notes on the D string... Eb and E show up wrong, F starts be to accurate.
Fretting notes on the A string, C starts to show flat when it's in tune. So there's definitely something weird going on around D3.

Is there any update on when this will be fixed?

EDIT: Using internal mic

[Marshall Johns]

We are looking into this now and trying to reproduce the error. We cannot duplicate so far so thank you to those who have posted additional information.

Please continue to post specific occurrences along with your model and OS version.

Your patience is appreciated.

[Scott Helmke]

We are looking into this now and trying to reproduce the error. We cannot duplicate so far so thank you to those who have posted additional information.

Please continue to post specific occurrences along with your model and OS version.

Your patience is appreciated.

I'm a pro audio guy, so if you want to send me test tones or something I could try that.

I'd really like for this app to work, because it's very cool and I'm kind of fussy about tuning!

[Scott Helmke]

Ouch.

Dead silence.

Not a good sign.

Progress? As I said, I'm happy to help out. On the flipside, I'm also happy to make a big stink about unresponsive vendors.

[Marshall Johns]

Hi Scott,

Thanks for checking back in.

My apologies. I didn't interpret your last reply to require a response. For expedited assistance and/or updates on this or any of our products, we are a phone call away. (Contact # is in all of my signatures.)

As previously mentioned, this cannot be reproduced on our side on the iPhone/iPod. We are not discounting the reports in this thread and doing our best to try to address them. We are releasing a native iPad version in the next few weeks that does have an improvement in the way the audio is handled and those improvements will be ported to the iPhone/iPod versions shortly. I do not have a specific timeline of releases but as they are approved and made available to me, I will post.

If the development group, requires a small beta platform of testers, I will create a new thread with the requirements for participation.

[Scott Helmke]

Well, not to make too big a deal about it... it's just the most expensive app I've bought, and at least for me it doesn't work right.

I do realize that there's a lot going on with product development and such, but here you've got a problem reported by several people at the least. A user who can reproduce the problem and is willing to be a guinea pig would seem to be just the sort of thing a developer would welcome, or at least that's the way it was when I was writing software full time.

So what's my way forward here - demand a refund, or hope that it'll someday be a fully usable product for me? I really do like my stroboclip tuner, and I'm pretty fussy about getting tuning right. And I'd like to have this app work just as well - I'm even willing to spend a bit of my own time since you can't reproduce the problem in-house.

[Marshall Johns]

Hi Scott,

Thanks for your reply.

I understand your position and appreciate the offer to invest your personal time to help isolate the issue. We always appreciate our customers particpating in our beta programs when available.

Upon approval of our iPad version (hopefully withing the next 2-3 weeks....we have no control over Apple's approval process), the plan will be to port the audio enhancements to the iPhone/touch versions.

These will be free updates available through the App Store.

[Scott Helmke]

Nice - Peterson sent me the mini-mic and guitar cable adapters so I could test those out. However, it looks like the same problem with or without the different adapters.

[Marshall Johns]

Scott,

Thank you for that update.

An update will be available soon for the iPhone and touch users per my previous post.

[Scott Helmke]

Scott,

Thank you for that update.

An update will be available soon for the iPhone and touch users per my previous post.

Hi Marshall,

Is there any new news on the update?

[Marshall Johns]

Hi Scott,

Sorry for my late reply. I did not notice your post was new and not part of the old thread.

Development is working on a new release currently. I'll post when we submit it for approval. That process has taken a few weeks typically. Not completely clear on the new features on this since it was just re-opened but I'll post those as well when they are made available to me.

For faster service, please email me at: mlj@petersontuners.com