Ask Terry McInturff anything that you want to...right here

[Terry McInturff]

Thanks, Terry.
You're a gentleman and a scholar!

No...thank you, sir!

 

[AnthonyL]

Terry,

You should write a monthly column for a Guitar mag a la Premier Guitar, Guitar Player, etc...

or should I say, one of these publications should be seeking you out.

 

[Terry McInturff]

Terry,

You should write a monthly column for a Guitar mag a la Premier Guitar, Guitar Player, etc...

or should I say, one of these publications should be seeking you out.

Why thank you very much! It would be something that I'd enjoy doing. But I enjoy this right here at TGP; spread the word around TGP as Id love to have tons of Q's!

 

[Jim DaddyO]

Thanks Terry! Maybe I will take it down to my buddies studio. I did the engineering, mixing, mastering on a couple of CD's for him. The EQ is more than decent there.

 

[Terry McInturff]

Thanks Terry! Maybe I will take it down to my buddies studio. I did the engineering, mixing, mastering on a couple of CD's for him. The EQ is more than decent there.

PERFECT! So he has a killer outboard rack unit for you, excellent. Let me know!

 

[Oz Hofstatter]

Terry,
I just want to let you know that Carolina Custom arrived safely at Austin Guitar House and it's one of the most incredible "humbucker guitar" I have ever seen/played/heard in my life, neck to neck to my beloved 2005 Gustavsson Bluesmaster with Taku Sakashita PAF Pickups.
You are the MAN!
Cheers,
Oz

 

[Terry McInturff]

Terry,
I just want to let you know that Carolina Custom arrived safely at Austin Guitar House and it's one of the most incredible "humbucker guitar" I have ever seen/played/heard in my life, neck to neck to my beloved 2005 Gustavsson Bluesmaster with Taku Sakashita PAF Pickups.
You are the MAN!
Cheers,
Oz

Many thanks Oz. Sounds like we have found the best voicing for you. Can do sir!

 

[Oz Hofstatter]

Many thanks Oz. Sounds like we have found the best voicing for you. Can do sir!

You got it!!!
Cheers,
Oz

 

[Terry McInturff]

Bring it on! I stand ready to answer any of your guitar related questions. All brands, all types, all years, and of course everything "TCM".

If I do not have the answer, I'll tell you why, and perhaps how about you can best get the answer that you are looking for.

 

[pukko]

First of all, thank you very much for sharing your knowledge like this! I'm very fascinated by everything you write.

I'm building guitars as a hobby and I'm currently building a hollow archtop singlecut. Have a look here if you have the time: https://www.thegearpage.net/board/index.php?threads/1152581&page=5

As I understand, you build solid, semihollow and fully hollow guitars and my questions are:

How do you determine how big the air volume in a body should be to achieve a certain character of sound in a guitar? I'm thinking body thickness/body width, how much hollow space there is inside the body and also how thick the top should be. As an example, if I build two guitars with the same materials but make one a wider body with a shallower depth and one with a narrower but deeper body, what will the possible difference be? What do you prefer yourself?

 

[Terry McInturff]

First of all, thank you very much for sharing your knowledge like this! I'm very fascinated by everything you write.

I'm building guitars as a hobby and I'm currently building a hollow archtop singlecut. Have a look here if you have the time: https://www.thegearpage.net/board/index.php?threads/1152581&page=5

As I understand, you build solid, semihollow and fully hollow guitars and my questions are:

How do you determine how big the air volume in a body should be to achieve a certain character of sound in a guitar? I'm thinking body thickness/body width, how much hollow space there is inside the body and also how thick the top should be. As an example, if I build two guitars with the same materials but make one a wider body with a shallower depth and one with a narrower but deeper body, what will the possible difference be? What do you prefer yourself?

Many thanks indeed and your project looks great!

Dang it...there is no way that I can even begin to answer your Q via the space and time constraints here...it is a huge topic, a big chunk of a career's woth of experience with these things cannot be compressed into a few paragraphs and that is frustrating; Im sorry!

One very insufficient comment (I must TRY to contribute SOMETHING!)
regarding your narrow/deep vs wide/shallow comparison

> Suppose that we have identical tops and these tops are thin enough to vibrate rather freely. For purposes of explanation lets assume that we have a 3/32" thick Sitka Spruce top.
And...the body is fully hollow.
And...the hollow airspace inside the two bodies is identical measured in cubic inches.
And...the width of the glue joint around the edges are identical width

In this particular instance the wide/shallow would have a lower overall sound. Why? Because the top is wider and will be want to pump up/down fewer times-per-second than will the narrower and thus stiffer top.

The slower motion produces lower freq's.

Make sense?

 

[SK Guitars]

Hi Terry,

I built two identical guitars. The necks from the same boards, the bodies from the same billets...all the way down to the headstock facings these two guitars are identical. All the hardware was identical. The guitars were made 100% with cnc machines so the geometry is near identical on both. The only difference is that one is highly chambered as shown and the other is a solid body except for the electronics cavity. I wanted to hear the difference, if any. This was a quest to challenge an assumption. I'd note that although this may seem odd...I owned a manufacturing business for twenty years making composite aircraft propellers. Testing assumptions is just a habit now.

I recorded a passage that I can play fairly consistently on both guitars and posted the clip here.

http://www.recordingproject.com/bbs/viewtopic.php?t=40311

I was surprised to hear almost no difference at all between the two....or at least with the vast difference in weight I expected much more. I believe I hear a slight compression with the solid body but it's so subtle I doubt too many others will pick it up.

I'd be honored to hear your thoughts on this. I very much enjoy your posts.

 

[Terry McInturff]

Hi Terry,

I built two identical guitars. The necks from the same boards, the bodies from the same billets...all the way down to the headstock facings these two guitars are identical. All the hardware was identical. The guitars were made 100% with cnc machines so the geometry is near identical on both. The only difference is that one is highly chambered as shown and the other is a solid body except for the electronics cavity. I wanted to hear the difference, if any. This was a quest to challenge an assumption. I'd note that although this may seem odd...I owned a manufacturing business for twenty years making composite aircraft propellers. Testing assumptions is just a habit now.

I recorded a passage that I can play fairly consistently on both guitars and posted the clip here.

http://www.recordingproject.com/bbs/viewtopic.php?t=40311

I was surprised to hear almost no difference at all between the two....or at least with the vast difference in weight I expected much more. I believe I hear a slight compression with the solid body but it's so subtle I doubt too many others will pick it up.

I'd be honored to hear your thoughts on this. I very much enjoy your posts.

Im honored to be asked and Ill be getting back to you once Ive had the chance to listen to your clips in my studio's control room. I never listen to clips on computer speakers, ear buds, or cheap headphones....if Im interested in actually hearing the clips well enough to form an opinion on something.

Thanks, and I'll be back atcha!

PS......before I listen to the clips, Id like to ask if you could record another pair of clips...one of each guitar...thru a high quality direct box, and send them to me?

 

[SK Guitars]

Im honored to be asked and Ill be getting back to you once Ive had the chance to listen to your clips in my studio's control room. I never listen to clips on computer speakers, ear buds, or cheap headphones....if Im interested in actually hearing the clips well enough to form an opinion on something.

Thanks, and I'll be back atcha!

PS......before I listen to the clips, Id like to ask if you could record another pair of clips...one of each guitar...thru a high quality direct box, and send them to me?

Aw...too late for new recordings as the guitars have been sold.

The signal chain has the guitars going into a Line 6 POD XT PRO, minimally processed, and then straight to the card and hard drive. I expect, after reading your previous posts, that you would want to hear fully unprocessed clips. Sorry about that. In any case the difference, or lack thereof, is the main point of interest for me. I was fairly surprised by the results of this test.

Btw...the pickups are Seymour Duncan P-Rails using all four coils.

 

[SK Guitars]

Here's some pic's pf the two guitars.

The red one now has SD Jazz and '59 humbuckers but it had P-rails in it when I originally set it up for the sound test.

Curious to hear your thoughts on this, Terry.

Btw...I make those pickup rings, volume knobs, bridges, and truss covers in my shop on large production machines.

 

[Oz Hofstatter]

Question for the Master:
- Can you educate us about the "angle between the neck and headstock" and the "angle between the neck and the body", how does it interfere on the playability, tone, etc.?
Thanks in advance,
Oz

 

[pukko]

Many thanks indeed and your project looks great!

Dang it...there is no way that I can even begin to answer your Q via the space and time constraints here...it is a huge topic, a big chunk of a career's woth of experience with these things cannot be compressed into a few paragraphs and that is frustrating; Im sorry!

One very insufficient comment (I must TRY to contribute SOMETHING!)
regarding your narrow/deep vs wide/shallow comparison

> Suppose that we have identical tops and these tops are thin enough to vibrate rather freely. For purposes of explanation lets assume that we have a 3/32" thick Sitka Spruce top.
And...the body is fully hollow.
And...the hollow airspace inside the two bodies is identical measured in cubic inches.
And...the width of the glue joint around the edges are identical width

In this particular instance the wide/shallow would have a lower overall sound. Why? Because the top is wider and will be want to pump up/down fewer times-per-second than will the narrower and thus stiffer top.

The slower motion produces lower freq's.

Make sense?

Yes that makes sense. Kind of like a big vs small cymbal or something like that maybe. I find these type of questions very interesting and it's feels a bit frustrating when you're a hobby builder with little to none experience of these kind of things. The ideal situation would be to be able to build a few guitars at the same time and try out different variations on the same theme to be able to tell the differences. Not really an option when building in your kitchen though... And every time I get the building itch again I want to try something different.

Another question: Do you feel there is a need to seal the wood inside the hollow guitar? I imagine that if you're having the wood at an ideal moisture level when building, why not seal it to prevent possible humidity problems ahead? A very thin sealer of course.

 

[bladerunner]

Hi Terry! I have read some of your posts here on the forum, so i thought I'd contact you hoping you could help me out with my case, since you seem to really know a lot about this... I'm currently having a one piece guitar built and it is pretty much done at this point... However, even though I have used carbon fiber reinforcements, I have run onto quite a few dead spots. Clamping the headstock took care of almost all of them, but it created a lot of neck dive, to a point where its really hard to play.

I did some research about it, and figured that I could try one of the two things:

1. Soak the neck in slow curing epoxy resin. A bit extreme, I know, but if what I read about dead spots is correct, it might alter the wood structure enough so that it the sound transition on the neck would be faster than the body, and thus, potentially avoiding the frequency cancellations which are causing the dead spots.

2. Remove the board, remove the carbon reinforcements, and put steel rods instead, to make the neck heavier. This would probably be similar to the headstock clamping, except that the weight would be equally spread across the neck, and thus, wouldn't cause so much neck dive, hopefully.

I know both of those seem a bit far fetched.. so any advice would really be welcome.

Thanks!!

 

[Terry McInturff]

Question for the Master:
- Can you educate us about the "angle between the neck and headstock" and the "angle between the neck and the body", how does it interfere on the playability, tone, etc.?
Thanks in advance,
Oz

This is truly one of those really good Q's, many thanks, Oz.

As always, every single fellow TGP builder is invited..with open arms...to contribute to any of the TCM discussions; I'd love to see more participation along those lines, there has never been very much but lets see that change!

This will be a bit of a term-paper and so, bear with me.

On to the topic, whilst I roast a chicken for me and my boy. Let me begin by first defining some terms; most, but not all of these are to be found in the general "Luthier's Lexicon" of terms at this time.

1) The "Speaking Length" of the string
The speaking length of the string is that part of the string which is free to vibrate between the nut and the saddle, or between the fret and the saddle; important to note that the bridge saddle is always "in play".

2) "Scale Length"
The scale length of a guitar is most easily described as the distance between the nut and the mid-point of the bridge; the fret spacing is different for each scale length as well, and to use two easy examples, on a Les Paul of 24.625" scale that number represents an average distance betwixt nut/saddle and the fret positions are placed accordingly; whereas on a Stratocaster the longer scale of 25.5" dictates a longer distance nut/bridge saddle, and also a wider fret spacing.

3) True String Tension
The amount of force, measured in pounds and ounces, that's required to crank a given string..of a given gauge/type up to the desired pitch. The shorter the scale length, the shorter the speaking length of the string and hence..less true string tension. A LP requires less string tension than a Strat to bring the same string set into tune.

4) "Percieved" string tension
A TCM term that I use to describe the changes in percieved string tension...percieved by the player due to differences in break angle on various guitar configurations.

5) Break Angle
A term that I (and doubtless, others) use to describe the angle at which a string meets the nut from the tuner, and also the angle at which it meets the bridge saddle from the tailpiece, strung thru the body, etc.

6) "High Profile"...to..."Low Profile"

TCM terms I use to describe the general height above the top that the strings, pickups, bridge, and tailpiece end up being as a result of the neck angle.

7) Neck Angle (aka, "neck pitch")

This refers to how steeply the neck, as a whole, tilts back in relation to the flat plane of the top; using our two examples, a LP will have a neck that has a steeper neck angle than a Stratocaster does.

8) Headstock angle (aka "headstock pitch")

This refers to how steeply the headstock of the neck tilts back relative to the straight plane of the neck. Any cursory examination of LP-vs-Strat will show that the LP has the very notably steeper headstock angle of the two.

Let's take a break in order to review and to understand these definitions before I move on.

 

[vrdyer]

Terry, do you feel that bone vs a graphtec nut has any significant differences in tone and sustain? Also, what type of bridge do you prefer? Larger posts in the body of the guitar? Aluminum, titanium, brass, etc? Last, how much difference do the pots on the guitar really make between CTS and others? Including orange drop caps?