Justin Zazzi's tuning companion for room eq wizard

Justin Zazzi

Wave Shepherd - aka Jazzi
This thread was originally on DIYMA and I am moving my support to here.

Note: See the link in my signature to download the latest version of this tool.


This spreadsheet has been a lot of fun to make! My goal is to take as much guesswork out of the tuning and installation process as possible. With this tool, you can calculate a safe high-pass crossover point for your midbass and midrange speakers, then plug those numbers into the next sheet where you choose what frequency response curve you want your overall system to have, and the tool will generate a set of custom house curve files tailored for each of your speakers. Import those directly into Room EQ Wizard and use the EQ module to find the filters for your DSP.


If you use the next sheet to calculate time delay settings for all of your speakers, and you get them to match the house curves exported from earlier, then your tuning is mostly done! I recommend spending some more time with 31-band pink noise tracks to get the center image perfectly centered, and you can download some ones I made from my dropbox at this link:


-----> 31-band pink noise tracks <-----


A bonus feature I included is an interactive chart to help you choose which size power wire and fuse for your amplifiers. The sheet will take into account the efficiency of your amplifier (effecting how much power it will need to be supplied with) as well as the condition of your car (engine on or off) and you can choose how much of a voltage drop is acceptable to you. Lastly, measure about how long the power wire needs to be and then you will see which size wire and fuse you will need. A ton of research went into this particular sheet, and I'm looking forward to everyone's feedback.


There is an included read-me with instructions for each section with some hints and cautions.


Like I mention in the included read-me, please let me know if this is useful for you and if you would like me to build more features into this spreadsheet.


Here are some screenshots:


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Thanks for bringing this over Justin. I got confounded trying to setup the curves and x-overs in REW, it was much easier to import and tune to the curves I made in your spreadsheet.

Where I really struggled was with which curve to use, I found i needed to carry my "bass" rolloff all the way to 1k, ie the Audiofrog curve sounded horrible to me, but some of the whitledge curves were a bit much. With more time and effort I'd like to individually tune to multiple cuves and then a/b test them, but even dialing in one tune is kind of exhausting, and so many times I A/B test and think "yeah that sounds good, and the other one sounds good, but does one really sound better than the other ?"
 
Yeah that's a tough thing. The best situation is when you have some global filters to play with then you can tune the system dead flat which takes a while, then use the global filters to more quickly dial in your overall house curve. I know that's not always an option for some processors though.

My radio has a pretty good equalizer on it so I've been using it as a global filter to fiddle with my overall response. It is very convenient too since I can adjust it anytime without a laptop or a phone app or whatever. Once in a while I'll take the small edits I've done on the radio and fold them into the dsp and reset the filters on the radio so I can continue experimenting.
 
Jazzi - I have been working with your Tuning companion and the Whitledge curves for a number of months with some difficulty.

I finally realized by using REW to measure the imported house curves that the slopes and crossover points created by your tuning guide don't actually reflect the crossover type selected in the guide. I'm wondering if it's just the nature of the house curve itself sloping downwards that changes the actual crossover slopes, or if it's something else I missed.

When I imported one of the curves into REW as a regular measurement, then went into the EQ window (with no house curve loaded in preferences), I could manipulate the default flat REW house curve target to match the imported Whitledge curve, and the results were usually something like a Bessel 36db/oct or a LWR 12db/oct, or something else entirely. The midrange curve was the one most frequently mixed, with the high pass usually being a 24db/oct LWR, and the low pass being something closer to a 12db/oct. The tweeter curve always matched up to 24db/oct. the Midbass curve high pass is always much steeper than 24db/oct. Is this something you already realized when creating this?

Anyway, this realization helped me reach the target successfully. It's a great tool! I thank you for creating it!
 
Yep, that sounds right, working as intended. The flavor curve (whitledge, Andy, jazzi, etc) will change how it looks just like you describe. Nice job learning how it works!
 
Separately, I would enjoy some feedback on wire gauge and fuse worksheet. I'm curious if it is useful or if it is easy to use or if it's just a messy confusion or what.
 
Shoot. Teaching online and a data collection and graphing day...not a whole lot for me to do but stare at initials on a screen wondering if the students are actually there or not...(I do at least get to see their work being done in real time, but the ones that aren’t doing anything make me wonder).
 
I think the wire gauge worksheet is useful. I've always found that graph to be useful (you can find a similar one through Crutchfield or a variety of websites).

One problem I can see is that different Class D amplifiers have different efficiency ratings. Usually they are close (75% vs 83%). But added confusion can happen with the class AD amplifiers. It might help to have an added option to input the advertised efficiency rating ... but then again ... would it be better to just round down for safety sake to the lower number?

For the voltage drop ... I think that some people will measure this and will know ~ what their voltage drop is, but it might be helpful to have a "recommended" or average voltage drop list. It may be best to have some sort of a default, that errors on the side of caution. Sometimes its good to have a short sentence or paragraph that explains the default so that the average joe doesn't change the default.

I personally have found myself on the borderline of 4 vs 8 gauge wiring. Sometimes I think that a little disclaimer is necessary that can explain the grey area. Its easy to engage in selective listening and read the chart and then look in your toolbox and draw a conclusion that is more in line with what you have in stock. When in a gray area, personally I like having a push towards black or white.

I have found that amplifier wiring calculators are somewhat common. RF has one, Kicker has one, Crutchfield has one, Sonic has one, etc. I think that this is an important tool for you to hone, but also I feel that a similar and less available tool is speaker wire gauge selection. There is a website (http://www.bcae1.com/wire.htm) that has a sometimes-great speaker wire calculator. One issue is that it only works on certain browsers (for me, Mozilla but not chrome). The second issue, is that after trying to find the sweet spot for what the extremes are for 10 gauge vs 12 gauge @ 1 ohm ... the calculator is broken. Sometimes it works and sometimes it doesn't. To me, this is a tool that can be improved upon. The calculators algorithms aren't perfect, nor are they consistent. I've tried to find the "breaking point" of how-many-watts@how-many-ohms, and depending on how I input it, I get different results.

I think sometimes its clear and easy to find a calculator to see what gauge wire our amplifier should need, but it isn't so clear that the same speaker wire that is ok for 100 watts, isn't OK for 300 watts (This was my realization when finding out what gauge wire was acceptable for my Stevens Audio MB-6 Mid-bass that can take oooooooodles of watts ... I'd rather only feed my speaker wire through my door boots once). But also, its handy to know what gauge wire is appropriate for most subwoofers, but at what point that wire isn't up to snuff. This can be useful because I was recommended 16 gauge wire for car speakers ... but had I picked up a 100' roll of 14 gauge I would have been able to wire my mid-bass speakers (with as many watts as they would ever want, regardless of ohms or future amplifiers), as well as my subwoofers.

5 paragraphs later ... One worksheet for speaker wire and amplifier wire seems like it would become a default search. A one stop shop.
 
Thanks for all the hard work on this Justin.
I'm trying to understand the Crossover tab better but am somewhat confused...
I'm building a 2 way front with a midbass (GS690) and a wideband (GS25). When I enter the driver data in the Crossover tab, it recommends 100Hz HP for the midbass (GS690) and 200Hz HP for the wideband (GS25) The excursion plot is well below xmax for both.
This seems kind of weird so I'm thinking I am missing something. Are these intended to be the MIN HP or absolute HP that I should enter into the 2-way curve fields?
 
You may want to edit the read me.txt to point to this thread rather than DIYMA. It would be unfortunate if someone went looking for help and accidentally fell into that dumpster fire.
 
Thanks for all the hard work on this Justin.
I'm trying to understand the Crossover tab better but am somewhat confused...
I'm building a 2 way front with a midbass (GS690) and a wideband (GS25). When I enter the driver data in the Crossover tab, it recommends 100Hz HP for the midbass (GS690) and 200Hz HP for the wideband (GS25) The excursion plot is well below xmax for both.
This seems kind of weird so I'm thinking I am missing something. Are these intended to be the MIN HP or absolute HP that I should enter into the 2-way curve fields?

Sorry I didn't see your question earlier!

These are supposed to be good frequencies to try if you have no other guidance to work with. I would consider them the minimum high-pass frequency for what you want to do, based on the numbers you type into the boxes. Yes the excursion should be be lower than the red Xmax line but that is the point, trying to keep you within the limits that you define. You can experiment by raising the Xmax value to something big like 100 and then play with the other numbers, hit the calculate button a few times, and see how it all changes.

Also remember this tool is a rough estimate based on some textbook "ideal" math. It doesn't work out like this in real life and the excursion is usually lower than my tool predicts so it might be considered a conservative tool for what it does (which is better than underestimating and giving you false sense of security).
 
Good to see you here Justin. Seems lot of people have moved away from DIYMA now. Hope the community grows in a healthy manner
 
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