5 way project - tapped, bass, mids and tweeter, big boy system

[Speedysteve7]

Yeah can't hide these - wife quite fancies my artist daughter painting some kind of wildlife scene with the tweeters featuring as woodland animals peeping out. I'm not so sure::-)

An even bigger room would be nice but £££'s is always the issue.

I would like to explore that DIY electronic x-over. I'll have a search but if you have a link that would be great.

3 wig-wammers popped over yesterday and had a listen - they want them to make it to Scalford!!! We'll see.

[bjorno]

Originally Posted by Speedysteve7

..did some measurements which showed I need to have a check over the lower crossover. Seems it crossing a bit high and there are a few ups and downs that were not predicted by hornresp. Room or driver variation perhaps.

Here's a sweep using Holmimpulse. 1/3 oct smoothed.


Need to revisit the throat size in the tapped horn vs the 100Hz peak and see or is it my crossovers?

Hi ,

Great job! Reminds me on one of my early seventies set-u p's(when I was a small boy)_instead of your TH I had big 30 Hz Schmack-horns.

I looked at your HR simulation yesterday, see the first resulting picture, cents of observations/conclusions:

A single folded TH of this size(~375L): Using a 2:nd order Bessel LPF is IMO not adequate if targeting a smooth integration with the Mains speakers(Upper Bass area). Even if the the TH is well cross-braced and stuffed with damping material starting from the throat side and half-ways down the line: Sound-stage hang-down is also expected(lower Midrange cues).

For Home use: IME,IMO a TH with Sd/S2 < = 1.5: 1 Smouth>S2 can be stuffed like an TL/TQWT or T-TQWT/T-TQWP in order to a great degree improve the SQ = Hi-Fi performance possible and only a marginally loss(blameless) of in-band efficiency.

The Pre-pulse is amplitude large( blue in picture) i,e. an near a blameless limit case. Should ideally be down less than 1/10 with respect to the Main-pulse, but will fuse as being within 10 mS, no signal delay is necessary for the mains.
Note the 'green' irregular phase-slope > than a critical BW= FR colorings.This phase should be brought down to improve good integration with your Main speakers..

Normally from my experience with HR and real measurements,even indoors is that they are very similar and only differs with some peaks and dips caused from the room influences.

IMO ,If you had posted a phase response too(,A single FR plot is worth less than 10% when looking at in total, especially for resonating enclosures) , you've told 50 % of the story and if added a non smoothen IR, nearly 100% would be covered.

Of course, it would be neat if you could post a non smoothen .wav IR file,,, here at DIYaudio...If not:
...Jumping to Sub-woofer forum where I almost found your identical posted design information: You are in good company here i.e. at 'sub-woofer forum', I don't recall seeing any measured IR posted ,or the very minimum: a printed one, that completes/reveals a useful (of quarter-waves relying sub) measurement that can be discussed analytically in order to avoid the typical nonsense text that often is added to the FR pictures in various threads.

today,I made an overlay on top of your recently posted measurement plot:The second of posted pictures:

A forth order filter seem adequate..a Bessel filter has no advantage over Bw or LR type of filter in this design as its more important for SQ reasons to suppress the off-band ripple than worry about 'timing' issues for the main IR and FR.

b

[Speedysteve7]

Wow thanks bjorno. I will take some time to digest what you have written. Quiet period at work perhaps:-)

1st thing I checked was the Zobel - I'd only mixed the Kappa 15A and Kappa Pro LFII zobels up! Sorted and it makes quite a difference but perhaps not enough as you say.
The Eminence do really seem to have a rising impedance and it needs controlling.

I will study further. I will take single driver plots soon too;-)

Kul att få kommentarer från en svensk. Jag klassa mig själv som halv svensk - bodde i sverige under 10år i Stockholm och Linköping, jobbade på Ericsson och Ericsson Radio.
Varit ihop med min svensk fru sedan 1986, gift med henne sedan 1992 och har två blonda tonåriga tjejer (barn).

Jag fortfarande data rejsa online med mina svenska sportvagnsklubb vänner och ikväll skall tittar på Wallander (svenskt version, den engelska versionen är bra gjort men fel, med engelskmän överallt i Skåne!). Att nästan alla pratar Stockholmska på dom svenska inspelningar är dock lite fel också:-)

+ here's some side on shots for fun




Where all the da bass comes from

[Jonathan Bright]

Hi Speedysteve7.
Here are the directions to get to the Ben Duncan HFN/RR 1981 active cross over.
Google "Saturn Sound Recording Services" go to the LHS options, click HISTORY then "The HiFi Section" and then "diyprojects". Fair bit of fine print but it is all there.........The cross over is of course nearly at the bottom of the page! That should do it.
Cheers, Jonathan

[Speedysteve7]

Thanks Jonathan. Interesting read / will need some serious digesting.

Any way back to the measuring of what I have...

All same crossovers but the Zobel's corrected on Tapped and Midbass drivers.
1/6 oct.

Tapped horn 90Hz


Midbass 90-330Hz


Mid horn 330-1250Hz


Upper horn, 1250-9000Hz


Tweeter 9000Hz up


All done from close to the listening position and at ear height.

Here is the measurement done again but with the mic very close to each horn mouth.

Tapped


Mid bass


Mid horn


Upper horn


Tweeter


So there you have it.

Quite a lot of room affect, as to be expected. But the lugs are telling me it's pretty good.

Now to fix that tube amp but worrying more about crossovers:-)

[ra7]

Have you looked at miniDSP? It'll make your life a lot easier with regard to crossovers.

[Speedysteve7]

Look at the above I realise I have much too big a mH inductor on the tweeter... Will have to fix that.

[Speedysteve7]

Yes was looking - all that ADC DAC though and 5 amps.

Originally Posted by ra7

Have you looked at miniDSP? It'll make your life a lot easier with regard to crossovers.

[Speedysteve7]

Listening now - sounding gooooooood.

[ra7]

The ADC-DAC part is not bad, but yes, 5 amps is a bit much. All those cables will ruin your life

You could do passive crossovers for the topmost part though, which will bring it down to 4 amps.

Another way to think about it is to do the bass and midbass section actively and then the top can be passive. That will save you a lot on big inductors and such. Plus, you can EQ to heart's content. The great thing about MiniDSP is on the fly adjustment - measure, adjust, measure... all from your computer.