Boston Acoustics GTA-800M @ 8 Ohms?
02-15-2011, 11:09 AM
#1
TECH Fanatic
Thread Starter
iTrader: (6)
Join Date: Feb 2009
Posts: 1,360
Likes: 0
Received 0 Likes
on
0 Posts
Boston Acoustics GTA-800M @ 8 Ohms? Since I believe my Lanzar Opti is fried, I was looking at low level amps to replace it. I saw that an authorized dealer was having a sale on BA amps, which from my research, is awesome brand (right?). Now, I do plan on adding a 10" sub or two down the road and for the low level amps, I was looking in the $100-$150 price range. They have the GTA-400M for $150 which is 400W x 1 @ 2 Ohms and for an extra $100, they have the GTA-800M which is 800W x 1 @ 2 Ohms and 500W x 1 @ 4 Ohms and appears to be BA premier amp.
1. Is this an awesome deal for this amp? Is the BA brand up there with Focal and what not?
2. Is resistance scaling linear? By that I mean, since doubling the resistance brings a reduction in power by 5/8 (from 2 Ohms to 4 Ohms), is it safe to assume 312.5W x 1 @ 8 Ohms?
3. For now I am powering (2) Bazooka 6.5" subs which are rated at 100W RMS. I figure if #2 is correct, then I can scale down the gain and bass boost, run DVC subs in series for 8 Ohms @ 157W each, and be modest with the power until I add the larger, more powerful sub(s) in a few weeks. This way, I don't have to buy a new amp to power that one (I am thinking (1) JL 10W7, not sure though). Is this a safe assumption and good match for down the road?
FYI, I do plan on getting the Opti rebuilt, but as it stands, I have no subs at the current time since I have no amp and need something quick to get away from just the highs. Let me know what ya'll think.
1. Is this an awesome deal for this amp? Is the BA brand up there with Focal and what not?
2. Is resistance scaling linear? By that I mean, since doubling the resistance brings a reduction in power by 5/8 (from 2 Ohms to 4 Ohms), is it safe to assume 312.5W x 1 @ 8 Ohms?
3. For now I am powering (2) Bazooka 6.5" subs which are rated at 100W RMS. I figure if #2 is correct, then I can scale down the gain and bass boost, run DVC subs in series for 8 Ohms @ 157W each, and be modest with the power until I add the larger, more powerful sub(s) in a few weeks. This way, I don't have to buy a new amp to power that one (I am thinking (1) JL 10W7, not sure though). Is this a safe assumption and good match for down the road?
FYI, I do plan on getting the Opti rebuilt, but as it stands, I have no subs at the current time since I have no amp and need something quick to get away from just the highs. Let me know what ya'll think.
02-15-2011, 12:22 PM
#2
2. Yes, power versus impedance is linear and it is exactly proportional (Ohm's Law). Doubling the impedance cuts power in half (not 5/8). The rating on that amp must be taking into account some inefficiency in the amp circuitry for it not to be proportional. So you can't predict output at 8-ohms because this particular amp may not even support an 8-ohm load.
3. If you have two Bazooka DVC 4-ohm subs then you can wire them series/parallel for 4-ohms total impedance. If you have two Bazooka DVC 2-ohm subs then you can wire them series/parallel for 2-ohms total impedance. So why would you want to use 8-ohms? Just be careful not to overdrive the subs with the amp you select.
3. If you have two Bazooka DVC 4-ohm subs then you can wire them series/parallel for 4-ohms total impedance. If you have two Bazooka DVC 2-ohm subs then you can wire them series/parallel for 2-ohms total impedance. So why would you want to use 8-ohms? Just be careful not to overdrive the subs with the amp you select.
02-15-2011, 12:31 PM
#3
TECH Fanatic
Thread Starter
iTrader: (6)
Join Date: Feb 2009
Posts: 1,360
Likes: 0
Received 0 Likes
on
0 Posts
2. Yes, power versus impedance is linear and it is exactly proportional (Ohm's Law). Doubling the impedance cuts power in half (not 5/8). The rating on that amp must be taking into account some inefficiency in the amp circuitry for it not to be proportional. So you can't predict output at 8-ohms because this particular amp may not even support an 8-ohm load.
3. If you have two Bazooka DVC 4-ohm subs then you can wire them series/parallel for 4-ohms total impedance. If you have two Bazooka DVC 2-ohm subs then you can wire them series/parallel for 2-ohms total impedance. So why would you want to use 8-ohms? Just be careful not to overdrive the subs with the amp you select.
3. If you have two Bazooka DVC 4-ohm subs then you can wire them series/parallel for 4-ohms total impedance. If you have two Bazooka DVC 2-ohm subs then you can wire them series/parallel for 2-ohms total impedance. So why would you want to use 8-ohms? Just be careful not to overdrive the subs with the amp you select.
