Anyway, i just would like some confirmation my results are correct as there is alot to rew i dont understand or even know if its applicable to what i am doing. All i used rew for was to see the frequency response and to e.q my portable speaker. The response you can see in pic 1 is how i got it now which to my ears it sounds really good, i cant imagine it sounding any better.

Pic1

The other tabs on rew; distortion, impulse, filtered ir etc etc. I do not understand even after reading up on them. I am assuming some of them are for room response which is not what im doing. But id just like to know if there is anything i have clearly missed or is obviously wrong and i could do better.

Let me know if there is other screenshots that i should post up for you to see. I just dont know which others are relevant. Theres only so much i can learn from googling.

I used winisd to design the woofer enclosure so if there are any screenshots youd like to see from that let me know. Air port velocity is just below 14ms & cone excursion is below its limit at the max wattage the amp will give.

Cheers 👍🏼

If your Microphone is MiniDSP, there is a forum as well that offers many using Room EQ Wizard for their personal needs. https://www.minidsp.com/support/forum" rel="nofollow - MiniDSP Forum

Best Regards, 

Thanks for the links too, i have already scoured the rew forum but not the minidsp one and i do use a umik1 so ill have a look at that. Im not using rew to e.q a room. Just using it in order to see a frequency response graph, using ground plane measurments.

As Norseman said though, we are in a similar place with no matter how much more i read i still dont know if the outcome is correct. Ideally i need clarification from someone expierienced that what i am doing is correct, and if not what to change or do. 

Yes, the black line is the Microphone Calibrated Frequency Response

https://avgadgets.com/ultimate-rew-tutorial-taking-measurements/" rel="nofollow - This Link  may help you along the way.

I am using the UMK-2 btw...

Best Regards, 

Im not looking to e.q a room. I am only using rew to see the response of my speaker and to e.q it. That part is fine. So all im asking really is the other tabs in rew; phase, IR, distortion etc etc. Are they relevant to what im doing now. 

Basically hoping someone could check it over, i would post screenshots of each section someone would need to see and theyd say "all looks good" or "that doesnt seem right".

I just want to make sure im doing it all correctly before moving onto my system. Where as this small 2way speaker is my 'practice' piece basically. 

It will show you the timing of the impulse response captured by the mic relative to a timing reference (loopback, or, when using a USB mic like umik, an acoustic timing reference from a separate full range speaker on channel 1/L

It sends a chirp to the fullrange speaker followed by a sweep to the main stack (for instance with kicks and subs soloed, and midtops muted

In this way you can see two impulses, one for sub to which you will ascribe a new t=0, and therefore see the delay needed to be applied to the kick to bring it in time.

Then you would mute the kick and sweep sub and midtops, set t=0 at sub again, and find the delay between subs and midtops, and apply the difference as delay to the midtops, bringing everything in line with the slowest cab (sub)

Now if when using the full system a musical element that played from say 50hz to 1000hz as one burst comes, the cabs all play at same timing for the listener.

The phase component of this I do not fully understand how to use.

Some say leave off the crossovers when testing , and select appropriate crossover type later at desired points in order to maintain phase coherence.

Others have said that for timing alignment, test with crossovers in place.

I have been unable to get a jargon free answer in which should be done, let alone how it should be done, so I shall follow along here keenly.

2. Gain match drivers

3. Select electronic crossover frequency. Use distortion graphs, and simulations/measurements at high output to assist crossover frequency selection.

4. Match crossover slopes of each drive unit at the crossover frequency to obtain summation appropriate for both on and off axis response. i.e do you want a reduction of gain, 0db gain match, or a summation boost at this frequency. Determining this assists the shape of the overall polar response and power response of the speaker.

5. Match up the start of the impulse responses of each driver.

6. Apply crossovers and align phase at the acoustic crossover point of both drivers via Overlay tab.

7. Measure both units together and confirm intended summation has occurred both on an off axis at crossover frequency.

8. Listen and shape input EQ to taste.

9. Adjust individual driver units gain/balance to taste.

10. Repeat steps 3-10 until satisfied with end result.

I think maybe steps 5 and 6 could be interchanged in order.

You can use the Waterfall and Spectrogram tabs to look for Time Domain issues, either linked to driver construction, enclosure construction, or room reflections.

Remember to donate to John, the author of REW and share your knowledge with others 

Thats a real good step by step too thanks, it will be much easier for me now to break down each section and try each bit and then research each bit if i get stuck.

A good start:

http://www.merlijnvanveen.nl/en/nl/studiezaal/166-subwoofer-alignment-the-foolproof-relative-absolute-method" rel="nofollow - http://www.merlijnvanveen.nl/en/nl/studiezaal/166-subwoofer-alignment-the-foolproof-relative-absolute-method

Also look at open sound meter, would make it a lot faster and is free.

this is to be done without crossovers in place?

Both usually, but I like to start without filter in place at low volume, making sure you do not put too much low frequency thru a comp driver, for example.

The idea being the natural response of the driver without crossover filters will sometimes assist in picking a crossover point.

For instance, in a standard 2-way 12" woofer + 1" comp, I'd want to know the natural acoustic rolloff that the woofer has in the top end, and the comp/horn combo has in the low end, prior to adding filters. Picking then, ideally, a point where both have low distortion, equal on/off axis response that would only be improved by electrical crossover filters.

Sometimes seeing the natural driver rolloff of 6db or 10-12db per octave, for example, will determine the electrical filter one could use, i.e to get a 0db sum at crossover, with 24db per octave acoustic slopes, would require only a 12db electrical filter, which might combine with the natural driver rolloff, to form the 24db acoustic crossover slope if that's the intended target.

Intended application may also play into the above, for example using the same pair of 12" + 1" combo for HiFi listening levels vs PA listening levels, one might be able to crossover lower in the HiFi setting with lower levels, thus gaining closer centre to centre spacing between the drive units.

http://www.merlijnvanveen.nl/en/study-hall/120-why-the-impulse-response-won-t-work-for-subwoofers" rel="nofollow - http://www.merlijnvanveen.nl/en/study-hall/120-why-the-impulse-response-won-t-work-for-subwoofers