Lab 12 Based Offset Driver - Mass Loaded - Transmission Line (OD-ML-TL) Design by Bj - Page 29 - diyAudio
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Old 12th January 2014, 04:08 PM   #281
tb46 is offline tb46  United States
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Default Post #280 - Felt and Damping

Hi NWCgrad,

David McBean has added the ability to add stuffing to the simulation, and it clearly indicates, that this enclosure would be best build w/ very little absorptive material, if any at all.

For the first test build I would not use any stuffing at all, or just a little around the S1 end of the duct. Remember, we really squeezed the last little bit of volume out of this box.

The reduction in cross-sectional area caused by the 1/4" felt would probably not hurt anything, but stuffing the duct should be done very lightly (and go for the less expensive stuff).

I wish bjorno would take a look at this, he knows so much more about this subject than I do.

Regards,
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Last edited by tb46; 12th January 2014 at 04:18 PM.
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Old 12th January 2014, 11:26 PM   #282
NWCgrad is offline NWCgrad  United States
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Quote:
Originally Posted by tb46 View Post
Hi NWCgrad,

David McBean has added the ability to add stuffing to the simulation, and it clearly indicates, that this enclosure would be best build w/ very little absorptive material, if any at all.

For the first test build I would not use any stuffing at all, or just a little around the S1 end of the duct. Remember, we really squeezed the last little bit of volume out of this box.

The reduction in cross-sectional area caused by the 1/4" felt would probably not hurt anything, but stuffing the duct should be done very lightly (and go for the less expensive stuff).

I wish bjorno would take a look at this, he knows so much more about this subject than I do.

Regards,
Thanks Oliver

Interesting...if I can get by without the felt I would be pretty happy as they don't give it away. Will try some light stuffing with fiberglass or pillow stuffing near the S1 end. Would be nice to reduce some of the calculated ringing above the LPF that could be audible. However don't want to reduce output.
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Old 17th January 2014, 03:37 AM   #283
NWCgrad is offline NWCgrad  United States
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Default and so it begins....

Finally picked up two sheets of 13 ply Baltic birch from a local vendor. Its grade A-1 and looks pretty solid. After forever I will make sawdust this weekend.
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Old 10th April 2014, 07:02 AM   #284
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PLEASE tell me you've built this and have heard how it sounds. I have a pair of LAB12's dying for an enclosure. I've been a fan of transmission lines for quite a while and have been wondering how I could do one that would fit in my car for these drivers. 2 of these side by side in my SUV would be a perfect fit.
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Old 10th April 2014, 01:00 PM   #285
DrDyna is offline DrDyna  United States
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Quote:
Originally Posted by qu1cks1lver56 View Post
PLEASE tell me you've built this and have heard how it sounds. I have a pair of LAB12's dying for an enclosure. I've been a fan of transmission lines for quite a while and have been wondering how I could do one that would fit in my car for these drivers. 2 of these side by side in my SUV would be a perfect fit.
Stick a Fosgate R1200d on a pair of them and you should be in for a serious "ear plugs necessary" type of good time.
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Old 11th April 2014, 07:13 AM   #286
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I actually have a silver face Fosgate T10001bd waiting for some subs to hammer on.
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Old 12th April 2014, 04:07 AM   #287
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Ahh the BD1000, good times, good times.

Those amps were sooooooo good, used to sell them.

pics?
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Old 13th April 2014, 09:47 AM   #288
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I can get some, I had a pair of them in my old truck on a pair of 15's in a 4th order.
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Old 13th April 2014, 02:20 PM   #289
DrDyna is offline DrDyna  United States
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Originally Posted by Etocynned View Post
Ahh the BD1000, good times, good times.

Those amps were sooooooo good, used to sell them.

pics?
Not to wander too far off topic, but I remember the Fosgate amps that were referred to as "cheater" amps..I think they were designed to run from 24v, but they were labelled like "50M".. which was actually a 500w if you cranked the voltage and ran it into half-ohm loads.

Then Harman took over.
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Old 20th April 2014, 01:35 AM   #290
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they_were_high_current_unregulated_amps.

Stable_to_.25Ohm,load_em_up!

Our_installer_had_6_running_30_DVC12's_in_his_blaz er,WOOMP!
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