[w 12]

Hey Sam..

That is a very nice offer from you...

I have already bought 4 similar drivers in Bangalore for my DIY project 2 weeks ago. ..some other DIyer can make better use of your offer..may take up on your offer some other time thx again

How ever keenly looking forward to pointers on Design parameters / calculations from Navin / others for Xovers, tweeters, bracing etc.....Looks like a cool learning experience.

[rareone]

Thnx Sam...

Since i am on bed rest for dayz coz had a small accident & injured my right leg... so i would send my bro to you to collect the goodie...

Thnx again...
will post the pix after the installation...

[Sam Kapasi]

Originally Posted by w12

I have already bought 4 similar drivers in Bangalore for my DIY project 2 weeks ago. ..

Please do share, on this thread, what you planned/plan to do with these drivers...

[Bass&Trouble]

Hullo All, and sorry for late intervention!

First to sort out some mysteries:

1. It is a Peerless India driver, 6.5" 4-ohm, poly chassis, paper cone, rubber surround.

2. It was used in the super economical ML line from JPW, UK. I still have very fond memories of those speakers, they sounded outstanding. I hate the fact that I dont have the ML910 or ML1010 parked in my living room.

3. It is a hi-fi driver, we're just lucky it's 4 ohms, otherwise usage in car would be very difficult. D'appolitos and all such other unpronounceable terms look good only in Navin's dictionary, and not your car. Trust me.

People are confusing the term 'woofer' here with subwoofer. This is nearly a full range driver, quite smooth and flat up until 4kHz and dips to 3dB below up until about 8-8.5 kHz. Plus side is since it does not have any break-ups etc, it CAN be used without a filter to roll off the highs by DIYers who dont want to get into complex crossover circuitry. There is no point in attempting a true 3-way since this driver has very very good midrange capabilities. Hence, Sam's jugaad crossover comprising of just a filter for the tweeter will work. But the 4.7 capacitor is debatable. It will depend on the tweeter, its impedance, the response curve, and the sensitivity.

As compared to a regular 6.5" car driver, this is more compliant; having a very low resonance frequency of just 35Hz for 11 grams of moving mass. To put this into perspective, consider that some car subwoofers that have a resonance frequency of 35 Hz have a moving mass of 100-200 grams and even higher sometimes. Translated, this means that the driver will be very dependent on the enclosure for bass reproduction. Dont expect to pop it just about anywhere and hear miraculous bass.

Dont expect them to shake you up if you use them in car doors and parcel shelves. These will produce good bass only with enclosures, and will hit really low and not boom only in ported ones. If you have to put them in the car, there are two possibilities: use them as dedicated midranges in a 3-way-ish setup. The midrange quality of this driver is phenomenal thanks to paper, and it is vulnerable to damage, again thanks to paper. So install it in places where you wont have water splashing on it, although the doping on the paper makes it fairly moisture resistant. The other option, for whoever thinks it's feasible, is to build accurate enclosures for them and have them sit in the trunk of the car. It is still not going to sound like your everyday subwoofer or even close to it, but it'll be really killer bass enhancement rear-fill for systems that sound too tinny with just the front speakers perched in the doors or dash.

In my opinion, the ideal use for these is really in homes. With such a flat driver, all you need is a half decent tweeter with a filter, and you're really set. I can provide the measurements of the driver if required, and you could really embark on a serious, stupidly-cheap high-quality home speaker project under the able guidance of Navin and the rather disabled guidance of myself . Some bookshelf models from the ML series used a really cheap 13mm polycarbonate tweeter. This is a good option. Peerless domes are not very expensive either but I'm not sure about their availability in the local market, almost everything is exported nowadays.

Sam: Indeed a very kind gesture (in addition to freeing up some not so kind real estate ). When I was 16, if I had come across an offer like this, I would be in your office doing a guzzler on you!

[Sam Kapasi]

B&T, spot on, spot on and oh, I almost forgot, spot on.


And please do post the driver specs. You're a good good man to have here.
And yes, I do want the kids to do the stuff we did when we were younger. Of course when Navin was younger, Elvis was King and Prince charles was a boy-but that is another story

[kooldude]

Originally Posted by Sam Kapasi

@dq -I do special deliveries for pune. Pick it up on Sunday from K Park.

@kd - call firoz na and take it from him

rareone - sure, you've got a pair.


Note: Account closed for now. First we will finish current deliveries. Then check stock. No more requests for 5 days.

Sam i called firoze he said he will give the drivers to me when you give it to him.So i would pick it up from him and thanks a lot buddy i thought if i took dem from you i would give u the pastries n the zippo anyways i would give that to you at next meet

[Sam Kapasi]

Pastries and a zippo?? My office is on the first floor above firoz's office I'm here all day.

[kooldude]

Originally Posted by Sam Kapasi

Pastries and a zippo?? My office is on the first floor above firoz's office I'm here all day.

Sure buddy but when do i come to pick them up and where is your office exactly

[desmoquattro]

Originally Posted by Sam Kapasi

@dq -I do special deliveries for pune. Pick it up on Sunday from K Park.

Thanks Sam. Where in KP and around what time can i pick it up from? Any contact points?

(er..i should have PMed this)

[Sam Kapasi]

kd- 397a/1b, naaz cinema compound, dr. bhadkamkar Marg, mumbai 400004, india, earth

dq- bad boy - email me your mobile number, will call you on Sunday from Cloverdale, KP. I keep coming to pune, my brother is a famous DJ there.

[Bass&Trouble]

Originally Posted by Sam Kapasi

B&T, spot on, spot on and oh, I almost forgot, spot on.


And please do post the driver specs. You're a good good man to have here.

There is a curve-parameters set on the Peerless website, but I don't know if thats accurate. I have asked for the line standard sheets to be sent to me. I will post it soon.

[navin]

Originally Posted by Bass&Trouble

1. It is a Peerless India driver, 6.5" 4-ohm, poly chassis, paper cone, rubber surround....It was used in the super economical ML line from JPW,

3. It is a hi-fi driver, we're just lucky it's 4 ohms, otherwise usage in car would be very difficult....This is nearly a full range driver, quite smooth and flat up until 4kHz and dips to 3dB below up until about 8-8.5 kHz....But the 4.7 capacitor is debatable. It will depend on the tweeter, its impedance, the response curve, and the sensitivity.

...a very low resonance frequency of just 35Hz for 11 grams of moving mass....

...In my opinion, the ideal use for these is really in homes....a serious, stupidly-cheap high-quality home speaker project under the able guidance of Navin and the rather disabled guidance of myself . Some bookshelf models from the ML series used a really cheap 13mm polycarbonate tweeter....
Sam: Indeed a very kind gesture (in addition to freeing up some not so kind real estate ). When I was 16, if I had come across an offer like this, I would be in your office doing a guzzler on you!

B&T you took you time didn't you. So please you see you, would have hugged you if you were here in person.

Sam, what did I tell you? *smiley* Remember I am old, very very old.

B&T, you can save me a trip to Rajiv's place (and Rajiv from getting a wedgie) by posting those specs (are the published specs reliable?).

Fs of 35hz. Mms 11gms. Qts? Vas? Cms? and Xmax (linear one way) or gimme voice coil gap and height.

Please see my post 122 and maybe we can give some of these guys a taste of DIY. I am not fond of those 13mm polycabonate tweeters. Almost as tizzy as those TS20s but given that they ar eok to 4K and roll of easily i'd condier a electrical 1st order with a suitable tweeter. Now that we are looking at 1st order i am getting a bright idea. what about making a series XO (a la Andy Graddon?). Now to find a tweeter that is happy 1st order at 4K.

Q: Wonder why Gunbir and Autophile have not found singed on this thread yet? I'll PM them.

[kkr2k2]

Originally Posted by Sam Kapasi

@dq -I do special deliveries for pune. Pick it up on Sunday from K Park.

do you do such special deliveries to hyderabad . i shall pay the delivery cost if required. hyderabad is in your map too isnt it

[low_bass_makker]

Originally Posted by Bass&Trouble

This is nearly a full range driver, quite smooth and flat up until 4kHz and dips to 3dB below up until about 8-8.5 kHz. Plus side is since it does not have any break-ups etc, it CAN be used without a filter to roll off the highs by DIYers who dont want to get into complex crossover circuitry.

Now the things are getting interested....

as it is a full range driver I would love to make it my home theater centre channel speaker.....sam bhai I would love if you keep a pair for me....I can easily get it picked up from your office in a day or two....so waiting for your confirmation.....

Also B&T sir can we have the Thiele spec so that Navin JI can comment further on the same......

[navin]

Gunbir, Autophile,

a) do you guys know of any suitable tweeter? The one that I think might work is a Philips soft dome unit with a Fs of about 1500hz. However for a 1st order series network I'd like a tweeter with a lower Fs.

b) Do you guys have any ideas that we have not yet covered. This might be the best chance many here have to DIY. We'd like it to be good. All opinions (however mad they might be) are welcome.

lastly on second thoughts since the woofer is 4 ohms if one has to use 2 woofers per speaker one would be limited to a series connection. few Home amps that this speaker will be used with will tolerate 2 ohms for long (or at high volumes).