Originally Posted by rlj5242
Can you rebuild the base or enlarge the opening for a 15" driver? What is your budget for the "better" 12 or even a 15? What drivers have you looked at?
Yes, the base could definitely be modified to fit a 15" driver ... When I built this almost 20 years ago, I was doing it on a very slim budget. I'm in a much different position now, and could definitely go for a quality 15" driver if it makes sense to do so
I think I'd be comfortable spending $200 - $300 for a better driver. I looked at Adire's current offerings, as well as Dayton and Eminence. All of their 12" drivers suggest a much smaller enclosure than what I have though.
Originally Posted by shivaji
Some 20 years ago when Adire hit the scene, I purchased their Rava sub, which houses the Shiva driver. It still works without any issues too.
Here is a pic from their manual on the specifications of the driver. It states that it can handle up to 650 watts.
Thanks for this! I used the Wayback Machine to try and find the original Shiva specs, and best I could find was this page with whitepapers on Shiva implementations (sealed, vented and passive radiator)
Shiva Page on Wayback Machine
Here is what is in the vented doc for amp selection:
Originally Posted by Adire Audio
2.1 Power Amplifier Selection
At first glance, Shiva would seem to indicate a need for a 600W amplifier, since that’s the power rating of
the driver. However, this is not the case. Very good results can be achieved with Shiva running from as
little as 40W per channel. Even smaller amplifiers (10WPC) can result in a musically satisfying
experience. It really depends upon your tastes and the capabilities of the loudspeakers paired with Shiva.
The 600W rating of Shiva is just that: a maximum power rating. This is the peak amount of power that can
be dissipated in Shiva over the long term. Realize that this level of power would yield an in-room output in
the 120 dB SPL range; this level is well beyond the typical continuous home listening environment.
However, assuming a source peak-to-average ratio of 25 dB (such as is typical for modern music, FM
broadcasts, and most soundtracks), listening at normal levels (80 dB SPL) would require peaks of 95 dB
SPL. This peak level requires 17.5 dBW, or 56.2W of amplifier power. As such, most home receivers
capable of 100W per channel performance will be quite suitable for use with Shiva.
We do realize that such listening levels (80 dB SPL nominal) are not for everyone. Some individuals will
listen to Shiva at higher levels. The 600W rating is intended to allow for those who enjoy musical peaks up
to and beyond 120 dB SPL in-room.
As with all acoustic transducers, we strongly recommend that you exercise good judgement when listening
to your loudspeakers. High power/high SPL capable drivers such as Shiva can cause permanent hearing
damage and actual hearing loss, if abused. Prolonged exposure to levels in excess of 110 dB can cause
partial or full deafness. Be kind to your ears!
My current amp (Carver a-400x) is rated at:
- 200wpc @ 8ohm
- 300wpc @ 4ohm
- 500w bridged @ 8ohm.
In hindsight, I wish I had opted for the dual 4ohm coil Shiva instead of the dual 8 ohm coil version they used to offer ....
The original amp I used when I built this was the Adcom 545 (100wpc @8ohm). I got the Carver some time afterward.
How are dual coil drivers rated? Is it 600w per coil, or 600w total (both coils)? It's too bad the Carver isn't stable at 2ohm, as both coils wired in parallel, for a combined 4 ohm load, then bridged to the Carver would produce quite an increase. Although I'm not sure the amp would handle it.
Since the Shiva is rated at 600w, it looks like I could just get a new amp rated for 600w
load, wire the coil in parallel, and it should perform well with a nice increase in output. Although my notes from back then suggest I'd hit the driver's excursion limit @ 30Hz with 200w. Although I don't recall how I came to that conclusion
Does your manual/document happen to have the TS parameters of the original Shiva driver?