RSD 500/1200, Alpine Type-R, Boston Acoustics

phonixx · Post by **phonixx** » Thu May 03, 2007 1:53 am

Now my new Amps and subs are up and playing. First i build the box for the 4 Alpine 10" R and placed it in my car. I hooked them up with a ZX450 but i didn`t get very impressed. I guess that gave them approx 150WRms each. Then i replaced the ZX450 with the RSD1200.1 and what can i say, the subs hit my backhead like a hammer. I guess the RSD1200.1 give the subs 300-350WRms each. The RSD1200.1 got tons of power and no matter how hard i pushed it its cold as ice. Then i replace my other ZX450 with a new RSD500.4 for my doorspeakers. I think they sound about the same.

The RSD1200.1 are my best Amp buy ever, its just brutal

Here is some pictures: Its not the best quality i took it with my cellphone.

Post by **stipud** » Thu May 03, 2007 6:37 am

That is a very impressive box. Do all of the subwoofers have the same volume of airspace? The ones on the outside do look a bit bigger than the inner ones, however it does look like you slanted the wood a bit to make up for that.

Post by **bdubs767** » Thu May 03, 2007 7:44 am

nice lets us know what you think of the amps

Post by **Bfowler** » Thu May 03, 2007 7:48 am

NIce work! you need to get a db meter on that!

Post by **VW337** » Thu May 03, 2007 8:31 am

Nice.

Any pics looking into the beasties from the cabin?

phonixx · Post by **phonixx** » Thu May 03, 2007 1:00 pm

Stipud:
The box is designed with Autocad, i have a friend that is very good with Autocad. The 2 in the middle is the biggest ones even if it does not look like that. I dont now the size in Cubic feet but in liters the 2 in the middle is 18L (1 gallon is between 3.5-4 Liters) with acoustical fill. The 2 on the sides is 14L with no acoustical fill. The box size is taken from the Alpine website. 14L with no fill is in "SPL" category and 18.4L with acoustical fill is in "Recommended" category. The wood is slanted yes.
One of the reasons to build this box so small was to spare some of my trunk and even to keep the sparetire and now i got more then half of the trunk with free space.

bdubs767:
The Amps is just wonderful. I hooked up the 4 subs with an ZX450 at first just to try it but to say it like it is...... it sucked. I thought that the ZX450 got some hidden power and was underrated and all that but it was not even close to kick the 4 Alpines. Then i replaced it with the RSD1200.1 and the differense was 2-3 times what i was hoping for. Its just a big box of raw power. The Alpines kicks me in the neck like a hammer and i`m a little worried about the back window of my old Volvo

I just never thought that the differense was that big from the ZX450 but the truth is that the ZX450 is not even close to the RSD1200.1 as a Subwoofer Amp. I`m not done with tuning the subsonic and the crossovers yet but after 2 days with those new amps i feel that the sound quality of the RSD500.4 is similar with the ZX450 but maybe i will change my mind when i am getting more used to the 500.4 but i really like the SQ of the 500.4 and it has a lot of power to.

BFowler:
Yes i will try to get a dB meter. It feels like they are playing loud.

WW337:
I took some pictures from the cabin and 1 from the trunk. Its not so easy to get pictures but you see 2 of the subs through the "skihole" in my backseat. I`m not done with the cables yet and if you look good you see that all the electrical cables are red

but i will replace the ground cables with black ones.

Pictures:

Post by **stipud** » Thu May 03, 2007 1:17 pm

Since the woofers are playing in a different sized airspaces, I would recommend you drill a large hole or two between each of the dividers, so that the woofers all share the same airspace. When you have a woofer playing in a smaller airspace than another, that changes it's sound characteristics. When you play woofers with different characteristics off of the same signal, you can cause cancellations. That is why we don't run 10's together with 12's, or different brands of subs... the concept is good, but in practice it doesn't work out that well.

By cutting the holes in the box, essentially there would be 16 liters per subwoofer instead of 18/14. The dividers will still act as a brace for the box, to keep it nice and rigid.

However, I don't think it will make such a big difference in your case, because the sizes are so similar. In this case I think the difference should only be theoretical.

phonixx · Post by **phonixx** » Fri May 04, 2007 1:17 am

I resized the pictures so we dont have to scroll sideways.

Stipud:
Thanx for the lesson about box sizes, i didn`n know that, lets hope its just theoretical.
The sound is very thight and loud and i really like it. Much tighter and much faster then the 2*12 Celestions in 2*50Liter ported box that i used to have. Its the first time ever that i build a sealed box because i have allways thought that a ported one is best but i`m not so sure anymore

The RSD Amps must be very very effective. Last night i drove a 2 hour trip and played some old school "2 Brothers on the 4.th floor" "Snap" "2Unlimited" "Magic affair" etc and the voltage drop in my car is gone. With the 2 ZX450 that i used to have i had a voltage drop when playing loud but with 1 RSD500.4 and 1 RSD1200.1 there is no drop no matter how much i`m pushing it and the Amps is stone cold. I have way more total power but less total current draw from my car system. Looks like the RSD Amps use all the current to produce sound instead of heat. I dont know but they hardly have any heatsink either and no fan so i guess the design must be different from some of the older amps like the ZX\Ti\MS etc.

Post by **Bfowler** » Fri May 04, 2007 7:33 am

behold the efficiency of class D amps!

actually they have quite a bit of heatsink, its just hard to tell because its on the bottom

Post by **stipud** » Fri May 04, 2007 11:16 am

Bfowler wrote:actually they have quite a bit of heatsink, its just hard to tell because its on the sides

Fixed.

The Xenons had the heatsink mass on the bottom, I think RSDs have the majority on the sides.

phonixx · Post by **phonixx** » Fri May 04, 2007 1:35 pm

There is some heatsink on the both sides yes. But i cant feel any heat on them no mather how hard i push them.

phonixx · Post by **phonixx** » Sun Oct 14, 2007 4:36 am

Done some upgrades on my cars electrical system. The work was done in Pedi`s garage and as usual the work was done in the middle of the night\early in the morning

Used a DMM with max\min memory and scoop and my cars electrical system was much weaker then i thought, found voltage drops down to 10.3 Volts

My original alternator was a little 55 Ampere Bosch. Now i got a 190 Ampere from http://www.excessiveamperage.com/ special made for my Volvo.

The difference is huge, now i got voltage drops down to approx. 13.5 Volts but i guess most of the drops is gone when i have done som cable upgrades betwen battery\engine\ground and between alternator\battery. I have bought some 2 Gauge i will be using for that. I will not remove the original cables so the total will be approx 0 Gauge. And the most important thing; theres a lot of power to get for "free" by preventing the voltage to drop. I guess i have got hundreds of watt more from both my 1200.1 and my 500.4 then i used to have with the old 55 A alternator. Thats for sure a real thing, not just theoretical.

Anybody know how much of the power is gone when the voltage drop down from 14 to 10-11 volts? Does it dipend on regulated\unregulated power supply in the amp?

Here`s some pictures from the alternators and the new cables, new battery terminals and the new 15 volts regulator for the alternator.