my first speaker build

[phoenix87]

hey all,
I want to build a small book shelf speaker as my first project . I have always wanted to build speakers. After reading much i finalized that it is best to start small experiment learn and go forward . As i am from india , many drivers are not available in my budget . So i found the smallest speakers with published Ts parameters and put it in WINISD to get the volume needed for a sealed enclosure .
I have selected the following drivers
MID BASS
PEERLESS 3INCH FULL RANGE S07NE
Fs- 100.78
Re- 3.43
Qms- 2.28
Qes- 0.66
Qts - 0.51
Vas(SD) - 1.27
Mms -2.67
Cms-933
SPL ref- 88.5
Freqency Response - 100- 10K

TWEETER
GRS 1TM-4 1" Mylar Tweeter 4 Ohm
BrandGRSModel1TM-4
Product Specifications
Tweeter TypePoly / Mylar DomeCone / Dome Diameter1"
Impedance4 ohmsPower
Handling (RMS)5 Watts
Frequency Response4,800 to 20,000 Hz
Sensitivity90 dB 1W/1m
Thiele-Small Parameters
Resonant Frequency (Fs)3,200 Hz
Find attached WINISD file , kindly tell me if iam doing it right .
And Iam not able to upload the WINISD file . Neways I am getting a sealed box volume of 1.4L.

regards

 

[S4m]

Sweet little box you are planning
I only want you to remember that if you want to build the enclosure,
add the volume of the driver itself to the enclosure volume.
In this case it would be something about 1.4l + ~0.5l.

Have fun

 

[phoenix87]

thanks s4m , does that mean my calculations are correct
???

 

[Inductor]

Yes. Anything between 1L and 1.5L is correct. Do listening tests, but I would prefer the higher Qtc of 0.8 than lower more laxed 0.7. You compensate for the rolling off after 150/200Hz.

 

[Inductor]

As another project (compare the two... infinite possibilities/alignments) you can make a bass-reflex, i.e. a 2-way box tuned to ~85Hz and volume/net -3L. Port: need a port about/for 4.4 cm/17.7 cm (diam/length). This will give you more 10dB's@80Hz (BR vs. sealed) for that matter.
There are a few interesting ideas around with forum members and other FR drivers.
For the TC9:
http://www.diyaudio.com/forums/full-range/283609-tang-band-8-full-range.html#post4544048
Tymphany TC9FD18-08 3-1/2" Full Range Paper Cone Woofer
https://www.madisoundspeakerstore.com/approx-3-fullrange/vifa-tc9fd18-08-3.5-full-range/
http://www.diyaudio.com/forums/full-range/148684-any-ideas-vifa-tc9fd-18-08-a.html
RS100, TG9, TC9, L3 and 830986 review. - Car Audio | DiyMobileAudio.com | Car Stereo Forum
https://www.youtube.com/watch?v=M0LatIrtoOg
Have fun.

 

[phoenix87]

After much thought I decided to scrap the previous en devour any follow a new route for my first speaker project i.e a 2way bookshelf speaker as my starting point .
Got the below mentioned driver and did the box calculation according to WINISD.

Listed below are the driver specs for the 5.25inch woofer

Electrical Nominal Impedance 4 Ohms
Resonance Frequency 63 Hz
Power Handling {IEC-268-5C} 40 Watt
Long Term Power {IEC-268-5L} 120 Watt
Short Term Power {IEC-268-5S} 200 Watt
Sensitivity (2.83V/1m) 91 dB
Resistance (DC) 3 Ω
Qms 4.61
Qes 0.44
Qts 0.4
BL 4.84 T-M
VAS 9.21 Liters


Mechanical Voice Coil Dia 25 mm
Winding Width 9 mm
Former Aluminum
Layers 2 Wire Type Copper
Magnet 80 mm
Cone Material Injected PP`
Surround Material Rubber
Chassis Stamped Steel, Powder Coated
Dust Cap PP Phase Plug

Specs for the tweeter
Nominal Impedance 6 Ohms
Resonance Frequency 1800 Hz
Operating Range 3,000 Hz to 20,000 Hz
Power Handling {IEC-268-5C} * 10 Watt
Long Term Power {IEC-268-5L} * 30 Watt
Short Term Power {IEC-268-5S} * 50 Watt
Sensitivity (2.83V/1m) 92.5 dB
Voice Coil Diameter 19 mm
Former Material Aluminum
Layers 2 Voice Coil Wire Type
Round Copper
Magnet Material Neodymium
Dome Material Aluminum
Surround Material Coated Fabric
Front Plate Type Moulded Plastic With Phase Plug

The calculated box volume comes to 9L with a port of 4.5CM Dia and 10CM length .And i am thinking of using a
2nd Order Linkwitz-Riley passive cross over with cross over frequency of 3000Hz to run them .

Am i proceeding in the right way , or have i done some mistakes ,if so some pointers would be very nice as i have yet not made the box and anychanges later will be a very costly affair.


regards

 

[prasi]

After much thought I decided to scrap the previous en devour any follow a new route for my first speaker project i.e a 2way bookshelf speaker as my starting point .
Got the below mentioned driver and did the box calculation according to WINISD.

Listed below are the driver specs for the 5.25inch woofer

Electrical Nominal Impedance 4 Ohms
Resonance Frequency 63 Hz
Power Handling {IEC-268-5C} 40 Watt
Long Term Power {IEC-268-5L} 120 Watt
Short Term Power {IEC-268-5S} 200 Watt
Sensitivity (2.83V/1m) 91 dB
Resistance (DC) 3 Ω
Qms 4.61
Qes 0.44
Qts 0.4
BL 4.84 T-M
VAS 9.21 Liters


Mechanical Voice Coil Dia 25 mm
Winding Width 9 mm
Former Aluminum
Layers 2 Wire Type Copper
Magnet 80 mm
Cone Material Injected PP`
Surround Material Rubber
Chassis Stamped Steel, Powder Coated
Dust Cap PP Phase Plug

Specs for the tweeter
Nominal Impedance 6 Ohms
Resonance Frequency 1800 Hz
Operating Range 3,000 Hz to 20,000 Hz
Power Handling {IEC-268-5C} * 10 Watt
Long Term Power {IEC-268-5L} * 30 Watt
Short Term Power {IEC-268-5S} * 50 Watt
Sensitivity (2.83V/1m) 92.5 dB
Voice Coil Diameter 19 mm
Former Material Aluminum
Layers 2 Voice Coil Wire Type
Round Copper
Magnet Material Neodymium
Dome Material Aluminum
Surround Material Coated Fabric
Front Plate Type Moulded Plastic With Phase Plug

The calculated box volume comes to 9L with a port of 4.5CM Dia and 10CM length .And i am thinking of using a
2nd Order Linkwitz-Riley passive cross over with cross over frequency of 3000Hz to run them .

Am i proceeding in the right way , or have i done some mistakes ,if so some pointers would be very nice as i have yet not made the box and anychanges later will be a very costly affair.


regards

go here http://www.diyaudio.com/forums/multi-way/250989-my-first-bookshelf-project.html
I was in the same phase earlier. But after actual building and tweaking the crossover, you will be much satisfied with SQ. I know I am so are people who have heard my stereo system.

 

[phoenix87]

thanks prasi for the link to your thread.I went through it ,didnt understand many things i guess thats to be expected . Neways I will keep on reading
For the time being i put the driver parameters in WINISD and got a box volume of 9L.
And I changed the port size to 4.5CM dia that gives me a port sound velocity of 0.07, which seems to be ok .
What i dont understand is why doesn't the box volume change when i change the tuning frequency below fs . I see a bump in the frequency response graph ,which then ,if i try to smooth out by increase the box volume ,doesnt happen .
Does this mean i cannot tune below the fs .
attached below the graph for 9L box with 63hz as tuning frequency.

regards

 

[prasi]

thanks prasi for the link to your thread.I went through it ,didnt understand many things i guess thats to be expected . Neways I will keep on reading
For the time being i put the driver parameters in WINISD and got a box volume of 9L.
And I changed the port size to 4.5CM dia that gives me a port sound velocity of 0.07, which seems to be ok .
What i dont understand is why doesn't the box volume change when i change the tuning frequency below fs . I see a bump in the frequency response graph ,which then ,if i try to smooth out by increase the box volume ,doesnt happen .
Does this mean i cannot tune below the fs .
attached below the graph for 9L box with 63hz as tuning frequency.

regards

You simply cant go on tuning the box much below Fs. It will lead to bad step response causing the sound to be muddy and also it would lead to port resonance. your design will cause excessive cone excursion at 40W below 50Hz.
Use unibox (an excel based utility) which is simple to use and provides guide values for parameters that you do not know. do some more reading on speaker design before jumping in. Read datasheets of foxtex woofer drivers as they give recommendations of box volume and port dimensions. try to simulate those drivers in unibox to understand why they recommend a particular dimensions for box and port.
reg
prasi

 

[phoenix87]

thanks prasi , for the pointers. Does the current data i.e box volume of 9L for a tuning frequency of 63Hz(Fs of the speaker) seem correct ???

Regards

 

[prasi]

thanks prasi , for the pointers. Does the current data i.e box volume of 9L for a tuning frequency of 63Hz(Fs of the speaker) seem correct ???

Regards

Yes its ok.
I would use
1. Fb-70Hz
2. Vb-9l
3. F3-62Hz
4. port 55mm dia x 115mm lt.
this will give a slight bump at around tuning frequency (1.6dB), which will give the feeling of better bass.
OR simply go with advice given by "Inductor". He has also helped in finalizing design of subwoofer. He is the "Boss".

However it all depends on accuracy of manufacturer TS parameters, they are known to vary quite a lot.
Box tuning is much simpler (you can vary internal box volume to some extennt and/or port length) compared to x-over tuning (read x-over design sticky thread by AlenB). I had to spend $$ on air core inductors/ polyprop capacitors. If you have access to enameled copper wire of appropriate AWG, you can make on your own inductor.
reg
Prasi
X-over freq of 3000Hz is too less for a tweeter with Fs of 1800Hz. select a different tweeter or go for slightly higher x-over freq, provided woofer is not in cone break-up region.

 

[phoenix87]

Thanks a ton... Prasi.... But. One problem... I have already aquired flared port of 45mm internal dia.... Will that create a lot of trouble... And about inductors... I will hand wind them on iron core... With 1.2mm enamled copper wire... And cross over frequency of 4500hz... Will make my life easier... Ss the inductors become small... I have attached the graph for the woofer... Doesnt seem to have a cone breakup at that frequency.... Please have a look i might be wrong

Regards

 

[phoenix87]

Made the bobbin for the inductors....

 

[prasi]

Thanks a ton... Prasi.... But. One problem... I have already aquired flared port of 45mm internal dia.... Will that create a lot of trouble... And about inductors... I will hand wind them on iron core... With 1.2mm enamled copper wire... And cross over frequency of 4500hz... Will make my life easier... Ss the inductors become small... I have attached the graph for the woofer... Doesnt seem to have a cone breakup at that frequency.... Please have a look i might be wrong

Regards

good, Use the 45mm, if you hear port noise, u can replace it with bigger dia port. u seem to have access to quite a set up, do i see a class D amp PCB in the background?, may be mistaken. may be a smps?

 

[phoenix87]

and i completed the inductors....
the inductor for the woofer has been wound with 16AWG or 1.2mm copper wire and the the inductors for the tweeter has been wound with 0.7mmX 2 copper wire .this difference in wire gauge is because i ran out of 1.2mm wire......after winding the inductor they were dipped in varnish to avoid vibrations .....
neways here are the pics...

regards

 

[prasi]

and i completed the inductors....
the inductor for the woofer has been wound with 16AWG or 1.2mm copper wire and the the inductors for the tweeter has been wound with 0.7mmX 2 copper wire .this difference in wire gauge is because i ran out of 1.2mm wire......after winding the inductor they were dipped in varnish to avoid vibrations .....
neways here are the pics...

regards

ur x-over will not work, especially if the tweeter and woofer sentivities are different. also increasing impedance of woofer with rising frequency would create problems.
I repeat again, "Read X-over sticky by AllenB"
All the best for your build.
reg
Prasi

 

[phoenix87]

yes prasi i do have a bit of access to electronics..And the electronics that u see is indeed a class-d induction loop amplifier , for the hearing disabled people. I have calculated the Lpad for my tweeter for a attenuation of 1.5db. to match the sensitivity of the speakers ....
thanks again prasi

regards

 

[phoenix87]

And the box building commences....

 

[Inductor]

thanks prasi , for the pointers. Does the current data i.e box volume of 9L for a tuning frequency of 63Hz(Fs of the speaker) seem correct ???

Regards

Port 4.5 diam@63Hz aligent 9L) is about 10cm L.

 

[Inductor]

Port should be what prasi mentioned 5.5cm for more than 30 W power. If using the 4.5diam & 70Hz then L is abot 7.4cm.