Now a Soviet Era Drivers for the Mets

My FR driver is 8" size, I have till now simulated over 7 woofers of 12", 15" and 18" including eminence, seas, Ahuja using Basta, but none of them have a better response on the low end compared to this Soviet era driver based on published data.

This intrigued me a lot and I want to discover if it's really true and hence building one. I will be following a minimalist approach for this as I don't have much h building experience with OBs. Will be fully trusting the simulator as of now.

I do have a pair of Bolton 10" woofers with me, but their SPL is suite low.

I don't have much personal experience with OB outside of hearing some but I also would second what Shafic says. 8 inch wide bander is unlikely to give satisfactory bass weight in an OB. My limited understanding is one needs something larger like 12" woofer with sufficiently high Qts of at least 0.7 to work in OB, to work along with the wide band driver.

Do check out this thread.
 
I don't have much personal experience with OB outside of hearing some but I also would second what Shafic says. 8 inch wide bander is unlikely to give satisfactory bass weight in an OB. My limited understanding is one needs something larger like 12" woofer with sufficiently high Qts of at least 0.7 to work in OB, to work along with the wide band driver.

Do check out this thread.
I have read many such post using 12"+ drivers in an OB for low end duty. Then back to the same question- is the simulator lying? I am fully aware that largish driver can push more air and their low resonance and higher Qts help. But the OB simulation in Basta for largish driver does not show better response than the Soviet era driver. This keeps me guessing and wondering. How can that be types? Only building myself and discovering could solve the mystery.
If time permits today and tomorrow, I shall try and post some example simulation for some standard 12"+ woofers vis-a-vis Russian drivers for a comparison.
 
Thanks Yogibear for your suggestions. I shall follow your approach. Due to ßpace constraints cannot go to big with OBs. If bass eventually turns out low, then will add my own TL Sub. This Wii be used from 100Hz down.
 
Comparison of 2 woofers vis-a-vis the Soviet Era driver.

Blue - Soviet Driver
Purpule - Ahuja 18" woofer
Red - Eminence Alpha 15A woofer

The eminence goes lower than the Russian driver couple of Hz with higher SPL. If done well can sound very good in an OB if space permits.
 

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Playing bass with same driver having 90+ dB SPL is difficult, it is better to have dedicated separate driver for that. Not that this 8" can not do such a wonder but is too much load and inviting distortion for the driver's perspective. Or else try some wonder drivers of Ahuja of 12".
Repeating, read posts of Dr. Jaudere if you want to.

If you are hell bent on using one driver, try the idea of Helmholtz resonating chamber with this driver. Or try cloth support.
 
I have seen the Hemlotz resonating chamber based OB speaker, but don't have space for that design. It's too deep imo.

The stated distortion for this driver is not much compared to Fostex measured values. Again only building and listening can confirm. I may think of using a simple BSC to level the response 500 Hz onwards to bring the mids and highs in level to the lows later if they sound bright.

If bass turns out low, I plan to use a TL sub, and put a 1000mfd capacitor to cut the bass on the FR.
 
Yeah, I would agree with Samir. A full ranger is supposed to be used without crossover or taming amplitude response. However, if it's shouty in the presence region, by all means try taming it a bit. There's nothing great about a honking widebander, IMO.
 
Yeah, I would agree with Samir. A full ranger is supposed to be used without crossover or taming amplitude response. However, if it's shouty in the presence region, by all means try taming it a bit. There's nothing great about a honking widebander, IMO.
I may add a parallel RC instead of a series LR, this way speakers are directly connected to the amplifier. The BSC will work in a bypass mode.
 
BSC works with infinite baffle or boxed enclosures and not used on OB designs. I think you should just place that driver in your baffle and let it sing by itself unrestricted / untamed by any passive components.

Is the driver already on its way ? Post Office or private courier ? Any estimates on total custom duties ?

You may already know but here a pdf on BSC:

http://www.quarter-wave.com/General/BSC_Sizing.pdf


I have seen this article couple of years ago and will not be following this approach. If at all i use, i will use a resistor in series with a capacitor and that will be connected parallel to the driver (similar to a zobel network). This way the driver property is not compromised and i can bypass some frequency as per requirement. This is usually tuned by listening than any calculation.

Driver was shipped 3 weeks ago, stuck in custom since 5th March, have contacted a clearing agent, not heard from him since last week. Hope the driver is delivered this week. Not received the BOE so dont know the custom duty till now. Its through India post (govt).
 
I do my India Post job import clearing myself. Takes half of a day and sometimes two visits to the PO.
But mine is still in custom, still lying in Foreign post office, Ballar Pier, Mumbai. I stay at Thane, very far off.
 
Hari, if you are willing to take a chance and experiment, this design may well click with your driver:

http://www.decware.com/newsite/ZOB.html

Its single driver design, very interesting with kind of indirect BLH. You may compare the specs of the driver used with your own driver TSP after it arrives.
Thanks for the link. Again i saw this but then again the depth of the Helmholtz resonator is quite high (16" in this case) preventing me to try this due to space constraint at my home. But neverthless, let me read this article to decide further.
 
With that baffle dimension, try the driver 8.75" on X axis and 36.75 on Y axis.
Thanks for the suggestion Keith. I did a quick simulation and this is what i get as attached.
The Red one is your suggestion and the Blue one is my simulation.
 

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