TH-18 Flat to 35hz! (Xoc1's design)

[Andy1967]

@Maan: Sorry for the late reply. They are stored in the city Naerum. What kind of jobs would your subs be doing?

 

[stewin]

hi all my xs project with monitor mids . have fun all

 

[stewin]

more photos

 

[stewin]

at play

 

[sbjacob]

Looks like a fun time man and I bet that system sounded great thanks for sharing that.

 

[BP1Fanatic]

Nice system!

 

[stewin]

thanks guys it sounded excellent. I thank GOD for this amazing forum diyaudio and all its wonderful members . also mr gs 1 and xoc1 GOD bless you big time for this cool post. stewin

 

[Brian Steele]

thanks guys it sounded excellent. I thank GOD for this amazing forum diyaudio and all its wonderful members . also mr gs 1 and xoc1 GOD bless you big time for this cool post. stewin

Hi Stewin, what driver did you use in your TH build?

Do you experience any issues with the bottom panel flexing to the point that the TH starts moving when you turn the bass up? I notice someone else drew attention to this and actually doubled-up on the bottom panel to stop this from happening.

 

[stewin]

I used new retone driver http://www.diyaudio.com/forums/subwoofers/190635-th-18-flat-35hz-xoc1s-design-168.html I did not have issues with the bottom vibration because I used 800watts . with high wattage I think bracing will be useful.

 

[Brian Steele]

I used new retone driver http://www.diyaudio.com/forums/subwoofers/190635-th-18-flat-35hz-xoc1s-design-168.html I did not have issues with the bottom vibration because I used 800watts . with high wattage I think bracing will be useful.

Thanks. I'm not familiar with that driver. It seems to have a B&C-like basket, but the rest is different. What are its t/s parameters?

My POC build is similar to the TH18. I can see that bottom panel is going to be a pain. I think I'm just going to double-up on it to reduce the panel flex.

 

[themmm]

Mivoc AWX-184

Hi!

I just finished reading almost everything in this Thread and i realy love this Speaker Design. As an absolute beginner in building Speakers, i just finished a Cubo 12 as my first project, and i asked myself if my 18" chassis would work with this Speaker Design.

I am not realy into hornresp and all the specifications yet, so it would be realy awesome if one of you more advanced people could tell me if this chassis would work in Xoc1's Design.

Speaker Mivoc AWX-184 (http://www.mivoc.com/gs/media/products/11804500_AWX184-Datenblatt_WEB.pdf):

fs 28 Hz
Qms 2.4
Qes 0.36
Qts 0.31
Xmax +/- 5mm

Thank you
themmm

 

[themmm]

Correct Link

http://www.mivoc.com/gs/media/products/11804500_AWX184-Datenblatt_WEB.pdf

 

[Zwiller]

Themmm, I simmed it and it works. The FR looks great but the 5mm xmax is the limitation... The most you are looking at is 120db @ 40Hz 1w/1m with 100W to xmax. Other drivers will get you another 6-9db (2-3x more SPL). You could always upgrade later once you blow it...

 

[themmm]

THX@Zwiller. Sounds good. Hopefully i will be able to start building within the next month. I will post the results!

If it sounds good the AWX-184 should be a cheap alternative to the other drivers as it costs only ~177$

 

[Sabbelbacke]

@themm
Mivoc most of the times states real geometrical xmax, so the AWX-184 is xmax-wise playing more in the 8mm region (like many oldschool 18s). It has a relative leight and soft cone and not as much "power" in the motor as most of the discussed drivers here. Besides the obvious lesser max SPL, this light cone has some difficulty keeping up with the pressure in the TH18. Of course, something will come out of this, but I´d rather go for some "more potent" driver - after all - its a lot of wood, a lot of work - why go low on the driver after putting so much effort in the cabs?

Said that, the AWX definitely is worth the money in reflex-boxes or bandpass designs.

 

[themmm]

@Sabbelbacke

Thanks for your advice. Is there any driver available in germany, that is not that expensive but able to drive the TH18? I think i will build the TH18 anyway and upgrade the driver later as suggested by Zwiller.

 

[djk]

The coil height (Schwingspulenhöhe) is 20mm, so the top plate is probably 10mm or so.

This gives a coil overhang of ±5mm, and an x-max of 7.5mm (+25% of gap height method).

It looks like a good affordable woofer.

 

[Zwiller]

Forgot how to estimate it but my gut was telling me the xmax value was conservative. With 7.5mm xmax you get another 2-3db and you are near 124db @ 40Hz with 225w 1w/1m. Played with the filter wizard and you want LR 24db HPF @ 20hz.

 

[djk]

5mm, 7.07mm, 10mm, 14.14mm, x-max.
0dB, +3dB, +6dB, +9dB more output.

 

[Sabbelbacke]

@Sabbelbacke

Thanks for your advice. Is there any driver available in germany, that is not that expensive but able to drive the TH18? I think i will build the TH18 anyway and upgrade the driver later as suggested by Zwiller.

We used most of the drivers mentioned above extensively in different designs. Rugged cones and high motor power simply cost money - and if you ever look at a klippel chart of a elektrodynamical transducer, you can see that the specs in the datasheet give only a little hintch on what is to expect... There are many speakers out there which look promising on the datasheet but loose in real world performance in a competition. In the case of this TH18, a rugged cone and horsepower do make a lot of difference (where in many closed or reflex boxes these factors are less important).

There is no "geheimtipp" for the TH - the mivoc will work in this cab, but it will not work as good as the more rugged speakers here...

If you want to take a "not pricy" speaker and then upgrade afterwards, choose one that has the same geometrical specs so you can swap speakers easy (e.g. PD has a totally different mounting diameter then EV). And buy a speaker which can be sould afterwards. The cheap china speaker which works fine costs a lot more money in the end because you can´t sell it, nobody wants to buy it.

Another speaker which works ok in this TH is the oberton 18xb700. good FR and can be sold easily in germany if not needed anymore.