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PostPosted: 23 Aug 2016, 18:49 
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Hi Folks,

I've finally got my shop mostly setup and I picked up a bunch of used woodworking gear so I'm gonna try get some speaker work done before the winter. I've always kept a close eye on the Audio Nirvana fullrange speakers and I got three pairs (4", 5" and 8") of their two newer product that I am going to fool around with this fall.

First up is the smallest of the bunch, the Audio Nirvana Classic 4+ Ferrite speaker drivers.

EDIT - The driver name was changed to Classic 4+ in Dec 2016.

Attachment:
Audio-Nirvana-Classic-4-Horn-Boxes.jpg

Attachment:
Audio-Nirvana-Classic-4-Horn-Packaging.jpg

Attachment:
Audio-Nirvana-Classic-4-Horn-Fullrange-Speakers.jpg


What attracted me to these drivers was the unique "camel bumps" on the paper cones. From the information I gathered, the purpose of the camel bumps is to refocus sound that would normally be directed toward the floor and ceiling towards the listener. That should make for a more detailed driver with more 'focus'. I was also thinking that the shaping of the cone should help make the cone stiffer and that could help with lower distortion (less cone flex). I'm going to try out the 4" driver in my open baffle system and they will cross-over at a couple hundred Hz. Fs is about 120Hz so they should be a good choice for this role.

Attachment:
Audio-Nirvana-Classic-4-Horn-Fullrange-Drivers.jpg


Nominal impedance is 8 ohms. From the datasheet the voice coil is 1.0 inches (25.4 mm), Magnet weight is 13 oz and the Total weight is 2.1 lbs. The driver cone is made of paper, black in color. The surround is accordion style and made of treated cloth. The black frame is cast aluminum. The build quality looks great.

I hope to get these mounted tonight and have should some more comments and listening notes soon.

Cheers

Update: See the Audio Nirvana Classic 4+ Ferrite speaker driver page for more info and photos including T/S parameters.


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PostPosted: 23 Aug 2016, 20:56 
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Efficiency?

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PostPosted: 24 Aug 2016, 00:05 
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Not much info on them... the 8" is 98dB.

SET time :D

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PostPosted: 24 Aug 2016, 04:14 
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Geek wrote:
Not much info on them... the 8" is 98dB.

SET time :D


My 15" concentric Baymas are 99db efficient so I know that is very effcient. Frequency range?

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PostPosted: 24 Aug 2016, 07:33 
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Frequency range?

Plenty of Info here: http://www.commonsenseaudio.com/nirvana.html


Specific to that speaker here: http://www.commonsenseaudio.com/an4hornspecs.jpg

Not bad at all for a 4" speaker.


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PostPosted: 24 Aug 2016, 18:56 
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The sensitivity is noted as 88.5 dB. When I dropped them in, I had to turn up the gain about 2 dB relative to the Fostex FF85WK drivers to balance out better with the bass component. BUT - these drivers are not nearly as bright as the Fostex drivers so I may have been over compensating previously. I won't know until I get the RTA out.

I didn't break in these drivers with tones, so I've only got 3 hours on them so far and much of that was distracted listening.

However, they are definitely different than the Fostex fair I've been playing with. The "camel humps" might be a very smart design. Normally I toe in with Fostex drivers so they cross before the listening position. For these drivers which are not as bright, I'm finding that no toe in is required and the benefit to that positional change is a wider sound stage. Also, my room is overly bright, but with these drivers I am not noticing it as much, perhaps again because of the focused cone? But it's still way too early to tell. The 5 inch unit has a normal cone so I will have a better idea when I listen to those how well the camel hump cones help focus the sound.

Cheers

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PostPosted: 24 Aug 2016, 22:31 
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All sounds good.

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PostPosted: 25 Aug 2016, 22:43 
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Here the drivers are mounted to the baltic birch baffle blanks. Had to use a wood preconditioner to prevent bleeding of the cherry stain. I was hoping for a darker finish. I think I needed to wait longer between the preconditioner and stain. Finished with a coat of polyurethane and it turned out ok. I'm new to wood finishing so I'm gonna try a different stain for the next baffle set.
Attachment:
Audio-Nirvana-Classic-4-Horn-Baffle.jpg

The frame is shallow and since I did not flush mount, I used 45-degree chamfer on the baffle so that there is room for good airflow. Also I like to mark the positive terminal the a swipe of red enamel paint.
Attachment:
Audio-Nirvana-Classic-4-Horn-Baffle-Rear.jpg

Here are the Audio Nirvana Classic 4_ drivers set into the open baffle speaker system.
Attachment:
Audio-Nirvana-Classic-4-Horn-Open-Baffle.jpg

A pair of oddblocks power the top end and the bottom 15" driver are powered with a DIY FirstWatt F5. The crossover is a Ashley. This weekend I should get a chance to do some good listening and post some notes.

Cheers


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PostPosted: 26 Aug 2016, 05:00 
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Lookin' great, Gio!

Gio wrote:
I was hoping for a darker finish.


When I did speakers, I tried various stains from el-cheapo-Rona-house-brand to really expensive furniture stuff. I settled on on the Behr stains from Home Despot. Want darker? Just keep adding layers and it has a wax-like finish when dry that buffs up quite well with cloth :D

Cheers!

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* Ratings are for transistors - tubes have guidelines*
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PostPosted: 26 Aug 2016, 05:21 
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I thinking trying to stain partical board super dark then multi-layers of polyurethane to give the appearance of a grain but barely perceivable. Just the baffle board.

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