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Messages - Iperfungus

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Guitars / Re: Dead spots
« on: Time Format »
Let's start by you listing each of the guitars that exhibit this problem, so we can see what they have in common.

I think the only thing they have in common are....strings!  :lol:
But I also use different gauges on those guitars: 9-42 or 10-46.

I compared an assembled Strat (vintage bridge, hard rock maple neck, rosewood fretboard, 21 jumbo frets, single action truss rod), a cheap Kramer Baretta Special (vintage bridge, hard rock maple neck, rosewood fretboard, 22 jumbo frets, single action truss rod), 2 Ibanez RG (a recent RG655 and a 1991 RG570, Edge bridge, 5 pieces maple/walnut Super Wizard neck and rosewood fretboard on the 655, hard rock maple/rosewood Wizard neck/fretboard on the 570 with scarf headstock joint, 24 jumbo frets, single action truss rod), my Traverso Silky (custom made, long scale, locking Schaller/Floyd Rose bridge, maple/rosewood neck/fretboard, 24 Dunlop 6100 frets, double action truss rod) and my new Arrogantia (short scale, Schaller Vintage bridge, Schaller locking tuners, zero fret, quartersawn maple/ebony neck/fretboard, 12 jumbo + 12 narrow jumbo Jescar EVO Gold frets, double action steel truss rod).

The funny thing is that the only one of the aboves that seems to have not the issue with dead spot on the G string at 12th fret is the Kramer....and the one that shows it more is the last Arrogantia.  :lol: :lol: :lol:
The other guitars stay in the middle...being worst than the Baretta and slightly better than the Arrogantia.

In any case, G string's sustain at 12th fret seems to have less sustain than other strings at the same fret or the same string at other frets in most of the cases.

On the Arrogantia I improved the situation with the following actions:

1) light frets sanding and polishing (now they really shine!)
2) better truss rod adjustment and neck relief
3) complete new setup with  9.5-44 strings

The dead spot is still there, but there's a little more sustain and a more natural decay.
I did not attempt to fix the issue on other guitars yet.

Now I've to verify what happens with my SG Standard and 1987 PRS Custom (these are known for having a lot of dead spots here and there all along the fretboard...maybe due to brazilian rosewood?).

By the way, this is something I can live with and forget.
When I bend the G string at 12th fret it sustains excellently and when I play the note it sustains enough to create not any real problem.

I assume Gale Frudua is right when he says that this is the nature of wood and instruments.
I'm just curious to see what will happen in the next years with neck's stabilization and woods seasoning and drying.
I also cannot tell if that frequencies are "killed" by maple or ebony...but I'm thinking about ebony, since all other guitars have rosewood fretboars...
Maybe that ebony have a particular density around 12th fret's area, who knows?

Guitars / Re: Dead spots
« on: Time Format »
Hey Max, I just tried my tele and it doesn't have the 12th fret dead spot, B 9th fret (G#) has an interesting harmonic after ring compared to 8th fret.  The was a post ages ago about tone woods and a good article about the various choices, anyway it said rosewood sucked tone which was why leo fender use a thin (almost veneer) rosewood fingerboard. (
I'll try my other guitars as they come out of their cases from time to time.

That's funny a lot!
Galeazzo Frudua is now a dear friend 'o mine and he as been my Master/teacher 2 years ago, when I started learning more about guitars reparing and lutherie: we had 5 day of training where he made me learn a lot of his methods and tricks.
I will see him here in Genoa next week!  :lol:
I will make him have a look...

He's a renowned pro luthier who has built electric guitars and basses for a lot of people (and many pros) for over 30 years.
Definitely, Gale is one who knows what he's talking about: that's a great article!!!

Guitars / Dead spots
« on: Time Format »
I found that many of my guitars have a dead spot on G string at 12th fret: less sustain and quick decay than other notes on other strings or same strings at different frets (there's also a wolf tone on B string at 9th fret....meaning an overtone when sustain ends...).
They are very different guitars and it doesn't matter the scale, strings gauge, set-in or screwed necks, neck wood and so on.

I've found that's a very common issue on many different guitars around the world, cheap ones or expensive ones.
It's not related to hardware, bridge, saddles, setup, frets and so on: it's related to neck resonance only.
Many people says they fixed the issue by adding mass to headstock in some way.

Do you guys have similar behavior on some of your guitars? Do you live with it and forget or did you attempt to fix it?
How? Did it work?

Let's go!!!  :banana-upsidedown:

@Ip, these are U13 (TC9176), as you can see in the schematic the output of the tubeboard goes straight into pin 3 of U13.

f*ck yes! Got it on the schema. the Output Level pot is related to U13?

Forgive the silly questions...but solutions to issues could arise from shred them in smaller pieces!  :lol:

Hey Max, the next stage after the tubes/ss is eq, the loop send/retrn is after that and then the chorus stage.  The chorus stage is always used as this is where the signal is split into pseudo stereo by inverting (180 deg) the signal into B.  If the chorus is IN it also applies very short delay (depth setting, more depth = more delay) to the B channel and rate (sweep modulation, varies the pitch (slightly) of B compared to A) between the 2 channels. So the eq stage could be overloaded at its input, and/or the chorus could be overloaded (depending on eq settings e.g. if you boost everything = more level). 

 :thumb-up: :thumb-up: :thumb-up:

However, I was intrigued by what you said about turning the main output to 0 making the squeal go away (and monitoring the signal elsewhere (loop send/phones out), this indicates (to me) something to do with the output section.

Yes, I'm quite sure it's something there as well...and for the same reasons you said.

@MJMP: Phil, when you said that this squeal could be related to some too high voltage to digital pots....which digital pots were you talking about in the signal chain/path?  :bow:

Guitars / Re: Arrogantia guitars
« on: Time Format »
NOICE. I was lookin' at those GT-1 pedals just before I found my Nova. Was the gain from the Blackstar or the pedal? Sounds like it was from the which case, that didn't suck at all.


The Blackstar was set to clean all the time.
The gain/drive you hear is from the GT-1 on a video and from a Boss DS-2 on the other (where I'm playing the Money for nothing main riff).
That small pedalboard isn't bad at all! Some "metal" tones must be reworked to be useful, but some other clean, crunch and overdrive or classic distortion presets are fully usable without being modified.
Interesting toy.

The funny side is how those pedals react to MAMA pickups...  :whoohoo!:
It's crazy and awesome!

...and it must be said that these Blackstar amps eat pedals in a wonderful, wonderful way.
The Boss DS-2 inside that small head gives you a very rich rock tone!!!


@ Max, interesting results with loop send and headphone out with output off.  So the loop send is before the chorus (IIRC after the eq, MJMP did post the signal flow a while ago), the headphone out is after the chorus (as is stereo) but before main outs (I think, or what you did wouldn't work), the headphone out also has rudimentary filters to reduce top end (similar to a cab sim).  So if you have lowered your trim pots to minimum (means with MDRT the tube stage is running much hotter  >:D ), this could be overloading the eq or chorus input ? (a guess  :dunno: ).

Hey Rich, yes...internal trimpots have been set that way already by Phil when he modified my MP-1, due to new MDRT voltage I assume: OD1 and OD2 trimpots are set to their lower value and there's plenty of gain still... :headbanger:
What do you think could be overloading eq or chorus? By the way, chorus is 100% off on my "gainy" patches.

By the way, the more I think about the issue, the more I'm convinced that the squeal could be an internal oscillation somewhere between the output of the tubes board and the input of a next stage, probably due to an overload under certain conditions: MDRT gives higher voltage to tubes, tubes are running hotter (and that's f**king good!!!) and maybe the stronger signal coming from there could be too high for some next stage when I rise gain and eq up.
The issue seems to be related to final output level and this is the reason why MJMP suggested to replace U10 and C56,57,48,49 at first.
Then we had some test comparison with MikeB and Herby and find that similar mods lead to the same issue...and here we go with the idea of adding a resistor.

Let's go on and I'm sure we'll come to a solution, so that we can run our MP-1s hotter than Hell and enjoy the fabulous tones coming out from them thanks to MDRT and other mods.
Should be this the problem, MJMP's idea of adding that 100K resistor could be the solution.

In the meanwhile I will manage to add the 100K resistor in series to R17, so we'll see what happens.
Should this be not enough, I still have the U10 OP AMP and 4 caps (C56,C57,C48,C49) to replace.

But I think that a "step by step" approach would be the best.

I'll have a look to my other MP-1's tubes board before I do anything inside my main one.  :lol: :lol: :lol:
If there's a reason for everything, maybe that MP-1 with all its issues could be here for this purpose.

Hey, that's the fun of being part of this place!  :wave: :wave: :wave:

I'll try the trim pot adjustment before I replace any components. But I won't get a chance this weekend.
It's funny, it never even occurred to me to adjust the output pot during my testing. I have mine pretty high, about 3 o'clock. I'll have to do some more playing around,  because I have plenty of headroom on the gmajor2 input pot.

I don't have any spare tubes to roll with.


You could try to lower the output pot until the squeal disappears...and see at which level...

Guitars / Re: Arrogantia guitars
« on: Time Format »
Sights‘n‘Sounds or didn’t happen C:-)

 :lol: :lol: :lol:

Some live videos from the lab...and a picture of what I use with her at home...  :headbanger:

We used a Blackstar HT-5 Metal head (clean channel) with a Boss GT-1 in the first video and a Boss DS-2 in the last...clean sound is from the little head (and a MXR Carbon Copy delay).
Recorded with a smartphone, so forget the quality...

Italian made Alnico5 MAMA Pickups...OMNIA series...they split like no others: true single coil tone!

Later the videos should be uploaded on YouTube as well..I will modify the post.

Hi Max,
Yes I did.  I didn't write anything down, thinking that I would remember, but of course I didn't.  So, I have just rerun some tests.
I have done this with both of my guitars.  I have done this with richards carvin ts100 as well as with my b200s.  I have even done this using a gcs-3 in the effects loop and going out to a headphone amp which pretty much proves that it is not a feedback issue.  I have done it with my gmajor2 in-line and active, in-line and bypassed and finally just going straight from my mp1 to the b200s.

I have an mdrt, noise mod and SS tube board.  I have a mullard short plate in 1 and Boogie STR in 2.

At one stage I used the gmajor2 parametric eq to isolate the frequency (but unable to completely eliminate).  It seemed to be at around 3000hz (this is the bit that I may have forgotten - Richard can you remember if this is what I said?).  Richard said it was around the Presence mark on the spectrum.  For the record, my mp1 is set up pretty flat.  Treble and presence are both 0, bass and mid not far away.

My main lead patch has OD1, OD2 and MV set at 6.5.  If any of those are higher then the squeal is present.

1. Keeping OD2 and MV at 6.5.  Adjusting OD1, the squeal is noticeable at 7.0 getting worse as the level goes up.  It is significant at 8.0
2. Keeping OD1 and MV at 6.5.  Adjusting OD2, the squeal is noticeable at 7.0.  Significant at 7.5
3. Keeping OD1 and OD2 at 6.5.  adjusting MV, the squeal is noticeable and significant at 7.0
4. OD1 on 10, MV at 6.5.  Adjusting OD2.  Noticeable at 5.5, significant at 6.0
5. OD2 on 10, MV at 6.5.  Adjusting OD1, Noticeable at 4.8, significant at 5.5
6. OD1 and OD2 on 10.  Adjusting MV, detectable at 5.0, significant at 5.5.

I quite like the tone that I can get even with these restrictions as it is so much better than it was before I did all the mods.  However, it seems crazy to be restricted to 6.5 on a scale that goes to 10.

MJMP, I am prepared to be the guinea pig for the resistor change, if you can tell me what I need to change.

Herby and Max, does this sound like the problems that you are having.  I had pretty much not thought about it for a long time because when it first started happening, I didn't map it out as completely as I have just done and MJMP said to just not put the levels up so high.  In retrospect, I should have pushed the point, as 6.5 is not really what I would call high.

Mike :waving-banana-smiley-emoticon

Thanks for testing Mike!
I 100% agree with you about all the better tones you get from MP-1 after those mods.
And I also agree with you that the squeal is not a feedback, also because I use home volumes here and it's there anyways...
It looks more like an oscillation, as MJMP suggested as well.

About the squeal, I get it with the settings of my main patch:

OD1 = OD2 = 7.5
MV = 5.5
Bass = 6
Mid = 6
Treble = 9
Presence = 12

I really love these settings, since the preamp has a very "plexish" tone...lot of details, no compression, tons of gain and open sound.
I loved it this way before mods and I love it more after mods.
The only problem with these settings is the squeal that comes out if I turn the front Output Level over 10-11 'o clock.
I did similar testing as yours and, at the moment, I can get rid of the squeal in 2 ways (without lowering overall gain, of course):

1) lowering Output Level (this means I cannot run outputs as high as I like)
2) lowering the EQ (this means I cannot have that "plexish" tone)

If I lower OD1-OD2-MV and EQ (bass, mid, high, presence) I can set Output Level to max without any squeal...but that's not MY tone.  :lol:

Internal trimpots for OD1 and OD2 have been set to minimum value already, after mods.

I also discussed the issue with MJMP by email and about the resistor he suggested to add a 100K resistor in series to R17 on the tubes board (430K --> 530K), to lower the input voltage of digital pots.
R17 is the more "external" of a group of 3 resistors in front of V2 socket.
As always, I'm very busy in these days and I did not find the time to do the job yet...but if MJMP confirms and you Mike would be the first one to do're more than welcome!!!  :bow: :lol:
MJMP suggested to replace some other components at first, but now I would attempt the R17 mod before doing anything else...otherwise we'll never know if it worked 100% to solve the issue...

A couple of questions: did you find any difference about that squeal with different tubes? I attempted some tubes rolling as well but I found no differences.
And how do you set front Output Level pot's value?

Another test I've done is to use loop send or headphones out (stereo with an insert Y cable) instead of main outputs: in this way, if I set front Output Level pot to zero and I use loop's level pot or headphones level pot, there's no squeal even with my settings....but, as I turn Output Level pot over 10-11 'o clock, the squeal is there...even if I'm not using main outs.
This makes me assume MJMP could be right about oscillation and a too high input voltage somewhere.

Guitars / Re: Arrogantia guitars
« on: Time Format »
Guys....the Beast is in da house...  :headbanger:

Guitars / Re: Arrogantia guitars
« on: Time Format »
@Magnus/SC: the kanji ideogram on the pickguard should represent Force...but...since you live in Japan...can you ask someone there to confirm that?  :thumb-up:
Hey Max,  just had dinner with my daughter and asked about your scratch plate, the kanji ideogram means force, strength, power and, as with all kanji, is based on the Chinese characters (as opposed to what I previously remembered/thought  :facepalm: i.e. that kanji is for foreign words  :nono: , that's Kara Kara  :thumb-up: , my bad).  This means force in an emotional context, not like the "force" that keeps an electron spinning around an atom (scientific context). So yes it does represent force or strength or power  :thumb-up:
Sumimasen, I'm late to the party  :facepalm:
The kanji is read "chikara" (phonetic Japanese: ちから) and has the meaning of strength/power/force. Its composed of "chi" which means "life" or "power" in a different sense and -kara which translates to "from"

Thanks a lot guys!!!

So this means Force in the Jedi way...  :thumb-up:
"May the Force be with you".

Chi is QI, the same of Tai-qi (taijiquan)...the internal force every human being has in the inside.

That confirms my thoughts about that kanji and its meaning is exactly what I wanted to have "printed" on the guitar.
The girl who did my tattoo warned me about being careful with usage of japanese and chinese ideograms, since if you use something being not sure about the exact meaning you risk to offend people. ^^

So I wanted to be sure I'm not telling someone "f*ck off you bastard of a motherfucker" when I show the guitar.  :lol: :lol: :lol:

Now, wait !....Do I have a another mp1 to mod  ? >:D

Do you want/need one???  :lol:

f**king great job!!!  :thumb-up:

Mmmm they do remind me a bit of Kreator and Sodom ??

...and Venom....old school guys!  :metal:

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