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Hardware Instruments => MiniBrute => MiniBrute Technical Questions - FAQ => Topic started by: Thunderroad75 on July 28, 2013, 01:35:35 pm

Title: tuning calibration
Post by: Thunderroad75 on July 28, 2013, 01:35:35 pm
Fired up the minibrute last night to find the tuning out over the full range of octaves. When i originally got the minibrute the tuning was stable after warm up and i had the tune knob set at 11 o'clock. Only the top octave would be slightly sharp.
 Now i find i have to tune the brute slightly everytime i hit the transpose buttons and i now have the tuning knob mainly  at 9 o'clock.
 How easy is it to calibrate the tuning and do i need to use a plastic, rather than metal, 2mm screwdriver just to eliminate the issue of shorting out the brute.
 One last thing it has been extremely hot down here in the south of england and just wondered if this could be factor in the problem im having.

 Any help will be greatly appreciated.
Title: Re: tuning calibration
Post by: tertior on July 28, 2013, 03:37:14 pm
It's better with a plastic screwdriver; but take care and go it very very slowly with settings.
Title: Re: tuning calibration
Post by: Thunderroad75 on July 28, 2013, 05:27:40 pm
Hi tertior,
 Thanks for the reply. Which way do I turn the calibration screw. Does it matter if the tuning is flat or sharp to determine the way you turn the screw?
Title: Re: tuning calibration
Post by: tertior on July 29, 2013, 12:55:15 pm
Hmmm, It is better to ask Bruno  of Arturia because it can also be a drift in the oscillator.
Don't touch it and speak with Bruno.
Title: Re: tuning calibration
Post by: synthi on August 25, 2013, 12:50:31 am
Could someone please send me a link to a plastic 2mm flat screwdriver online?! I can't find one anywhere!  ???
I''m based in the UK.
Thanks  :P
Title: Re: tuning calibration
Post by: Thunderroad75 on August 25, 2013, 08:27:51 am
Yeap got the same issue. Ive looked everywhere online and in local shops! ::)
Title: Re: tuning calibration
Post by: bartleby on August 25, 2013, 08:34:27 am
they are availabe from this ebay seller (http://www.ebay.de/itm/1set-Plastic-RF-IF-Core-Adj-Screwdriver-4pcs-complete-/140391623405?pt=LH_DefaultDomain_0&hash=item20affe2aed) and from reichelt[link removed] - and probably from just any electronics store?

[post edited for better clarity]

[additional edit: reichelt link removed, as apparently the item it linked to doesn't fit - sorry about that]
Title: Re: tuning calibration
Post by: beefinator on August 25, 2013, 03:56:54 pm
You could just whittle a Knex rod or the like into a screwdriver shape.  That's what I do.  Easy enough.
Title: Re: tuning calibration
Post by: tertior on August 25, 2013, 07:07:30 pm
Take a insulated screwdrivers and do not touch the metal. :o
Title: Re: tuning calibration
Post by: Thunderroad75 on August 25, 2013, 09:38:37 pm
Take a insulated screwdrivers and do not touch the metal. :o
That's ok but what if you suffer from a nervous disposition! Bit like playing operation!  :o
Title: Re: tuning calibration
Post by: bartleby on August 25, 2013, 10:13:38 pm
well like i said, you can find them both on ebay and at reichelt.
both the links i provided above will lead you to a set of plastic 'adjustment tools'.
Title: Re: tuning calibration
Post by: Thunderroad75 on August 25, 2013, 10:45:24 pm
Arh checked out your link. Thanks.
Title: Re: tuning calibration
Post by: synthi on August 26, 2013, 12:53:02 pm
Thanks bartleby just ordered from reichelt.
Title: Re: tuning calibration
Post by: bartleby on August 26, 2013, 08:10:09 pm
sure thing. edited my earlier post for better clarity, btw. it originally looked as if i was only linking to ebay and reichelt, not to the items you guys were looking for. :)
Title: Re: tuning calibration
Post by: Thunderroad75 on August 26, 2013, 10:22:22 pm
I check out reichelt but found it will be too expensive to send them to England. Just bought a set from Ebay for 5. I'm happy with that  ;)

Thanks for link Bartleby.
Title: Re: tuning calibration
Post by: synthi on August 29, 2013, 07:27:27 pm
Thanks to Bartleby it was the wrong screwdriver and its metal lol. It didn't fit.
All good though, these things happen...I know you were just trying to help.
Thunderroad could you let me know if the ebay link works out?
Thanks
Title: Re: tuning calibration
Post by: Thunderroad75 on August 29, 2013, 08:20:52 pm
Hi synthi,
 Sure thing once they arrive I will post on here what I received.  ;)
Title: Re: tuning calibration
Post by: bartleby on August 29, 2013, 08:31:10 pm
@synthi: oh. which one did you get? the set from reichelt? and they have metal blades? and neither is the right size? it does say one of the two has 2mm blades. or is it the shaft that doesn't fit?

anyway, i'm awfully sorry i pointed you in the wrong the direction.

but the ebay one clearly like it's all plastic, doesn't it? so i'm hoping that one at least will work.
Title: Re: tuning calibration
Post by: bartleby on August 29, 2013, 08:35:44 pm
here is another link to anther calibration set from reichelt (http://www.reichelt.de/Fine-Screwdrivers/ABGLEICHSET-3/3/index.html?&ACTION=3&LA=2&ARTICLE=118446&GROUPID=563&artnr=ABGLEICHSET+3). this one definitely looks like plastic, and the shafts look narrower than the other one, so this one should probably fit. but it's also more expensive. so let's hope that the one from ebay works ok...
Title: Re: tuning calibration
Post by: Thunderroad75 on September 05, 2013, 05:47:39 pm
synthi,
 Finally received my non conductive, plastic screwdriver set from ebay today. It took 7 days to arrive from tiawan. It was well packed and no problems with delivery, shipping etc.

Inside the pack was a plastic wallet with 4 different plastic screwdrivers. Quality is not brilliant but adequate and there is one screwdriver in the set that works perfectly with the VCO tuning and trimmer adjustment pots.

 So thanks for the link from bartleby.

I'm still waiting for a reply from Bruno regarding the tuning on my minibrute. Not sure if the unstable/ drifting tuning is down to it being very hot at moment or that there is an ongoing problem that needs addressing.

So Bruno please reply to my emails as I have sent you three and I have now been waiting over two weeks for an email back from you! :'(
Title: Re: tuning calibration
Post by: Rokk on April 14, 2017, 10:05:59 pm
Since calibration seems often necessary I'd like to add my experience. I just finished calibrating my minibrute as its tuning was way off. the uppermost C was 25 cents sharp and the lowest C 25 cents flat. In the middle octave the difference between the low C and hi C was 15 cents and that was too much for me. With calibration I could get it within +- 4 cents throughout the range with some E notes being a bit sharper or flatter and the lowest C being 15 sharp, then D 10 cents sharp and E 7 cents sharp and then F already within the said +-4 cents. Even the highest C is spot on. I'm very happy. I suppose nothing can be done about the lowest C, right? Or is there a solution? That would be great, but even with this anomaly I think it's fine for a VCO synth. Far better than the ATC-1 I had which had tuning all over the place with each note being in its own universe.

I didn't use a plastic screwdriver as they are hard to find. I just insulated a metal one entireliy, so that only the top remained metal and it worked fine.

I highly recommend this calibration.