Help me understand SD's Bass / Mid / Treble rating system

[che_guitarra]

Each pickup in the Seymour Duncan product line has a basic EQ profile, broken down into bass, mid and treble. Dimarzio has a similar thing.

Now I realise either company is unlikely to have a room full of Albert Einstein types sitting in front of oscilloscopes with complex mathematical formulae to determine each pickup's B/M/T rating. But it has to be a system of some merit. Otherwise, why would each and every pickup have it's own (basic) EQ profile graphed out?



Leads me to ask - in ballpark terms - i'm wondering how does Seymour Duncan define the bass spectrum, the mid spectrum, and the treble spectrum?



I ask this as I have an upper mid bump in one of my guitars i'm trying to annul via pickup selection... well, it's what I consider to be upper mid... the question is, does SD define upper mid the same way I do?

I just want to make sure I am on the same page as SD when taking each pickup's EQ profile into account.

 

[dave74]

Re: Help me understand SD's Bass / Mid / Treble rating system

My thinking would be that every pickup model will have lows/mids/highs that center in their own unique spot.
I think the graph is just a measure of it's generalized curve relative to it's own output.

 

[darthphineas]

Re: Help me understand SD's Bass / Mid / Treble rating system

Like the respective mag output ratings for the companies, I've found the EQ chart to be similar. It's not quite apples to apples to apply one EQ chart to another brand and think it will apply. Best thing is to try a few models from each brand, look at the EQ chart and base a bearing on what you hear.

 

[CB434]

Re: Help me understand SD's Bass / Mid / Treble rating system

Speaker companies like Celestion give you a proper graph over the whole spectrum which is quite helpful IMO, but generally the pickup graphs are quite inaccurate and hard to quantify. It seems to simply be a guess based off of people's impressions, or gut feeling. And 3 bars aren't nearly enough to compare the difference, in terms of lower mids, upper mids, lower treble, upper treble etc. So that the pickups look similar on paper but seem quite different when hearing them properly.

You'd do better with SD pickup choices to somewhat ignore the graphs and ask for people's impressions of the pickup or listening to videos of them IMO. Dimarzio are a bit more representative but still very loosely based on the real pickups. IMO they should be viewed as a very rough blurry outline of the basic pickup EQ, because it's easy to see two pickups to have the same EQ on paper but sound very different in person.

For example, if you wanted a JB sound without the upper mid bump, people describe the Suhr SSH+, Suhr Aldrich, Dimarzio Norton or AT-1 as having this characteristic, but that's based on discussions about the pickups, not a graph.

 

[Silence Kid]

Re: Help me understand SD's Bass / Mid / Treble rating system

Speaker companies like Celestion give you a proper graph over the whole spectrum which is quite helpful IMO, but generally the pickup graphs are quite inaccurate and hard to quantify

I still do wonder why pickup companies don't market with the same sort of graph.

 

[Parked]

Re: Help me understand SD's Bass / Mid / Treble rating system

I've wondered how they make the ratings. If you look at an equalizer with a middle showing boost on top and cut on bottom what's the middle ground for the pups?

 

[thanaton]

Re: Help me understand SD's Bass / Mid / Treble rating system

I still do wonder why pickup companies don't market with the same sort of graph.

Because the truth is that pickups don't work that way.

This is what pickup response plots actually look like when you treat them like a speaker:

This is from Fishman Fluence marketing materials.

As you can see they are flat through the bass and mids and differ in the high end response. The perception you get of their being a difference in bass, mids and treble independently is a consequence of overlapping this response with the inherently complex harmonics of six guitar strings. A pickup that has a given "BMT" as a neck pickup would not seem to have the same "BMT" if you put it in the neck, because it's those harmonic amplitudes combined with response curve that results in a final audible impression.

The BMT could be done in some consistent way, but it would be a painstaking task and you'd want to disclose the process you use if that's the case. Given that Seymour Duncan's BMT is just for marketing to consumers, and they don't disclose their method, it's safe to assume the BMT values are just made up, based on someone at Seymour Duncan's personal feeling about each pickup. That's not all bad, but since the particular guitar the pickup is in will create a different harmonic content, a pickup with a lot of bass in a Les Paul might not have a lot of bass in a 335, etc. It's not accounting for the fact that the particular guitar being used would have contributed somewhat to that BMT impression.

 

[che_guitarra]

Re: Help me understand SD's Bass / Mid / Treble rating system

That graph is awesome. Visual reference is a great aid for thinking through my problem.

If my problem range is 1.5 - 2.5K, looks like I want a humbucker with a more prominent treble roll off.

Tone Zone or an AT-1 might be the best bet here. Maybe even an EMG, but that will be a PITA to install with a Sustainiac already in there.

 

[AlexR]

Re: Help me understand SD's Bass / Mid / Treble rating system

The BMT is almost meaningless - especially since the last web redesign disaster. It needed overhaul even before then, but figures and graphs may well have been wrongly transposed - so you don't know what pickups actually have still got the right bars.

As to 'upper mid bump'......thats probably a job for an eq pedal. Unless you currently have a JB in there atm which is the only pickup I know of that actually does have an upper mid issue.

 

[darthphineas]

Re: Help me understand SD's Bass / Mid / Treble rating system

Visual reference is a great aid for thinking through my problem.

check out post #2 in this thread: https://forum.seymourduncan.com/showthread.php?162198-Resonant-peak&p=2100671&viewfull=1#post2100671

featuring this chart:

 

[thanaton]

Re: Help me understand SD's Bass / Mid / Treble rating system

That graph is awesome. Visual reference is a great aid for thinking through my problem.

If my problem range is 1.5 - 2.5K, looks like I want a humbucker with a more prominent treble roll off.

Tone Zone or an AT-1 might be the best bet here. Maybe even an EMG, but that will be a PITA to install with a Sustainiac already in there.

That graph is just a generality and not perfect, for example it shows Strats as having a higher dB output than humbuckers, which most everyone would agree is backwards.

Referring back to that graph though, notice there are "humps", or resonant peaks, and it's mostly the case that when a pickup has a prominent upper mid range such as the JB, it's because that hump is down in that mid range frequency. By switching to a lower output pickup, you move the hump further to the right, and that "flattens out" the problem frequencies, or by getting a hotter pickup, you move the hump to the left, and eliminate the problem frequency completely, as in it's not flattened out, it's totally attenuated out. IMO, it makes more sense to get lower output pickups so that you have a flatter frequency range with which to shape the EQ curve. You can eliminate high end though a number of means, but you can't put it back in once a hot pickup has shunted it all out.

 

[beaubrummels]

Re: Help me understand SD's Bass / Mid / Treble rating system

check out post #2 in this thread: https://forum.seymourduncan.com/showthread.php?162198-Resonant-peak&p=2100671&viewfull=1#post2100671

featuring this chart:

I think that chart would be better served drawn as a side-by-side bar chart. The frequency response is not a continuum across the SD line.

The problem with the BMT is that most of the issues players have with pickups happens in the frequencies in between the B, M and T.

 

[darthphineas]

Re: Help me understand SD's Bass / Mid / Treble rating system

I think that chart would be better served drawn as a side-by-side bar chart. The frequency response is not a continuum across the SD line.

The problem with the BMT is that most of the issues players have with pickups happens in the frequencies in between the B, M and T.

No doubt. It's a bit of a mess. But more relevant in a Duncan forum that charts of other brands.

 

[EDX]

Re: Help me understand SD's Bass / Mid / Treble rating system

well, it's hard to make a non messy chart that compares everything, you could do 5 charts, one for each parameter and then pile them, that might work as a good visual reference

 

[beaubrummels]

Re: Help me understand SD's Bass / Mid / Treble rating system

No doubt. It's a bit of a mess. But more relevant in a Duncan forum that charts of other brands.

I'm not knocking the data, just that it's hard to read. It's good info. For my own benefit, I'm going to try to redraw it.

 

[che_guitarra]

Re: Help me understand SD's Bass / Mid / Treble rating system

As to 'upper mid bump'......thats probably a job for an eq pedal. Unless you currently have a JB in there atm which is the only pickup I know of that actually does have an upper mid issue.

I dare say my upper mid bump issue is a result of the body wood - black korina. I didn't know what the tonal properties were going to be with this as a body wood, so I didn't really know what pickup to go for. I took a gamble with a SD Custom (SH5).

Obvious now that the upper mid bump of the black korina combined with the mid scoop of the SH5 is not the best pairing... or more accurately, not the best pairing for the outcome i'm trying too achieve. Sounds very 21st century metal - i'm shooting for something with a more 1980s/1990s vibe.

 

[thanaton]

Re: Help me understand SD's Bass / Mid / Treble rating system

I have a feeling the ceramic magnet in the Custom might be responsible for the perceived mid scoop. If you wanted more mids, I think a magnet swap might do the trick. Isn't a Custom Custom or a Custom 5 just the SH-5 with difference magnets?

I actually think that if the guitar already has mids inherently, then its probably a darker guitar... not so much mids as a lack of highs, at least that's my experience with all mahogany solid bodies, which is similar to korina. I wasn't happy with them until I went with something closer to "hot PAF" output, like Pearly Gates.

 

[AlexR]

Re: Help me understand SD's Bass / Mid / Treble rating system

Its funny, but of all the guitars I have with Korina I've not come across them being upper mid problematic. Of course I don't have the SH5 in them nor am I shooting for metal tone.

But in terms of wood, its always how the whole thing combines more than 1 section that makes for how a guitar sounds......

 

[EDX]

Re: Help me understand SD's Bass / Mid / Treble rating system

if he stick an A5 or A2 on his custom it would only sound worse (custom 5 has less mids than normal custom, as the effect of A5 mag on a wind designed for a ceramic is less mids, a custom custom might seem like a way to go, but the effect of A2 on the custom wind is a very spongy and at the same time somewhat lacking bass that only really works well on alder strats, on most other guitars it gets muddy), there are probably only 2 action routes, a custom 8, or if still within the 21 day exchange policy period just change to another pickup family

also for a proper pickup recommendation you must say what guitar and gear you have, since you say it's only this specific guitar then the gear ain't the culprit, but it helps so we can recommend something that will bond better with your gear and give a nearer approximation or even nail your desired tone.

also 80's/90's is a too loose tone range, megadeth doesn't sounds the same as sodom or overkill, nor they sound anything alike pantera, death, accept, helloween, dio, gamma ray, chastain, racer x, cirith ungol, agent steel nor candlemass. To name a few, you might want to specify what you think is 80's/90's vibe.

 

[che_guitarra]

Re: Help me understand SD's Bass / Mid / Treble rating system

...nor am I shooting for metal tone.

Neither am I. But sum of the parts right now, 21st century metal would appear to be it's best suited application. I'd rather it be a guitar made to suit players like Dave Navarro or Jerry Cantrell.