Back into bass, got a weird problem.

Beatin'

CarAudio.com Elite
Nov 18, 2012
1,011
2
Have 2 audiotechnix strato 15's in a 4th order at 2 ohms on a PPI black ice 1800.1D. I tuned it to the head unit at 25 out of 35 to give 500wrms at 2 ohms with a 60hz 0bd tone with a multimeter and got over 31volts at the terminal. I figured if a turned up to 30/35 it would give around 1000wrms, which is what the amp is rated at 2 ohms. Dont know how many notches actually give you that but it was loud and sounded appropriate.

I added a third battery and decided to wire down to half ohm. I tuned higher on the headunit, 30 out of 35, to get 31volts at the amp terminals, which would give about 1900-2000watts maximum amplitude with a half ohm load(amp rated about 1800wrms at 1 ohm). Hooked everything up, sounded good but was really soft at full volume compared to 2 ohms!? wtf? I checked the impedance of the subs, they're good. What did I do wrong?
 

Beatin'

CarAudio.com Elite
Nov 18, 2012
1,011
2
  • Thread Starter Thread Starter
  • #3
it's not rated at half but considering how large the amp is with the number of caps and transformers in it, I dont see why it shouldn't be able to put out what it's rated to do at 1 ohm, but at 0.5 ohm instead.

I can't figure this out. I saw around 31volts on the multimeter. At half ohm thats 2000watts. 🤔
 

1aespinoza

Junior Member
May 22, 2013
1,769
493
What did I do wrong?
If the radio goes up to 35, you have to set your amp gains with radio volume at 27 (bass boost off in radio and amp, bass in EQ all the way up, bass knob halfway). If the amp is not rated for 1/2 Ohm load, you will be pushing it too hard and it will run out of "steam' during use. It does not get a chance to fully recouperate expended energy so bass output will dwindle with each consecutive hit. The amp is in danger of overheating and burning out. You may also clip your subs at this point.
If amp is rated 1800w RMS then that is what it can safely put out all day. Max power is what you may see in a "burp", and is usually a number acheived in the most optimal conditions. I would completely ignore max claims.
 
  • Like
Reactions: Daryl rsv4

dragon.breath

Senior VIP Member
10+ year member
Nov 22, 2007
858
192
Sounds like you are running up against the protection circuit. Some amplifiers limit the power output when wired to low impedances.
 
  • Like
  • Thanks
Reactions: Buck and audiobaun

Beatin'

CarAudio.com Elite
Nov 18, 2012
1,011
2
  • Thread Starter Thread Starter
  • #6
Sounds like you are running up against the protection circuit. Some amplifiers limit the power output when wired to low impedances.
I think you may be right. But I've checked the manual and did google searches and such a feature has never been advertised on the old black ice series, only on one of their newer amps. But that does sound like that's what's causing the lack of output.
 

audiobaun

CarAudio.com Veteran
5,000+ posts
10+ year member
Jun 28, 2011
11,753
653
Sounds like you are running up against the protection circuit. Some amplifiers limit the power output when wired to low impedances.
Absolutely agree with this. The LAST RESORT OF THE PROTECTION CIRUITRY. That amp will eventually blow. Given time and the heat introduced
 

Beatin'

CarAudio.com Elite
Nov 18, 2012
1,011
2
  • Thread Starter Thread Starter
  • #8
I dont understand how so many others run their amps at half ohm even though they're not stable. Do they not have that kind of protection circuitry or do they just turn up and fight against the protection feature?

.....Should I fight the protection circuitry?💩
 

some dude

CarAudio.com Regular
Sep 7, 2020
140
62
It sure sounds like .5ohm is not a good idea and that your equipment does not like it. All signs point to no, right? If you don't care if it dies then go for it, sounds like it will. Make sure you have good fusing for the possible smoke show so you don't also burn your vehicle down, assuming you care about that too. ;)
 
  • Like
  • Thanks
Reactions: Buck and audiobaun

Coolhand20th

CarAudio.com Elite VIP
Mar 27, 2019
2,371
740
IF that is the newer PPI Black Ice series the Triangle looking one then no it isn't going to run at 0.5 ohm. Those newer Black Ice are just not comparable to the old ones that PPI used to put out long before they were sold. Those older ones were about the last of the good PPI Black Ice series they had.
 
  • Like
Reactions: Buck

Beatin'

CarAudio.com Elite
Nov 18, 2012
1,011
2
  • Thread Starter Thread Starter
  • #11
It sure sounds like .5ohm is not a good idea and that your equipment does not like it. All signs point to no, right? If you don't care if it dies then go for it, sounds like it will. Make sure you have good fusing for the possible smoke show so you don't also burn your vehicle down, assuming you care about that too. ;)
I just bought the car a month ago too. Yeah I'm not trying to burn down my car.😓 Gonna have to settle for a 2 ohm load and 1000watts.

IF that is the newer PPI Black Ice series the Triangle looking one then no it isn't going to run at 0.5 ohm. Those newer Black Ice are just not comparable to the old ones that PPI used to put out long before they were sold. Those older ones were about the last of the good PPI Black Ice series they had.
I have the older one that is black with the copper writing/trim on it. 15lb beefy motherfker lol.😂

It's just frustrating that I have the electrical and I never experienced 2000watts on this setup. So sad....😞
 
Last edited:

djdilliodon!

CarAudio.com Well Known
Nov 12, 2021
395
318
I just bought the car a month ago too. Yeah I'm not trying to burn down my car.😓 Gonna have to settle for a 2 ohm load and 1000watts.



I have the older one that is black with the copper writing/trim on it. 15lb beefy motherfker lol.😂

It's just frustrating that I have the electrical and I never experienced 2000watts on this setup. So sad....😞
Sell the amp and get yourself a taramps smart 3k, HD3000, or HD2000 and you’ll get 3000watts @ 2 ohms or 2000 watts @ 2 ohm 😈.
 

Buck

Why so Sirius?
5,000+ posts
10+ year member
May 19, 2008
28,416
1,144
I dont understand how so many others run their amps at half ohm even though they're not stable. Do they not have that kind of protection circuitry or do they just turn up and fight against the protection feature?

.....Should I fight the protection circuitry?💩
The people that I know that truly and safely run .5 ohm have expensive amps and run a ridiculous amount of electrical now, like multiple alts and a lot of wires and high voltage charging. A lot of these people’s dc voltage never fluctuates much.

The box type is related to electrical flow in the amp, with the way the box controls the cone movement and therefore how the coil moves through the magnet guass/field, which then changes the impedances your amp sees at relative frequencies. Box size, port size, location, type of box, so many things can factor into electrical control of the amp over the woofer, due to how it changes cone movement across frequencies.

So, some people can run .5 ohm, or I even know people who’ve competed at .25 ohm, because they have expensive amps, super expensive/extensive electrical setups with huge capacitance of higher voltages (like charging at 15ish volts), and the box is designed to help control impedance spikes and dips, especially playing music, which is a huge factor in stressing your amps.

How your sub moves in and out directly changes the active resistance against electrical flow in the woofer at that specific point of movement. Audio is a bunch of small things that all add together that allow you to maybe be able to run .5 ohm.

I ran 1.4 ohms on 2 strapped amps, so 2 ohms is like 1 ohms, and it would cut out rarely, but always during a large frequency changes, like a sweep or punch or just low to high note; those are the things that seem to wildly change impedance, which wildly changes the fluctuating stresses with the amps. One key thing to sense impedance from the driver’s seat is to always have an accurate reading of a dc voltage meter plugged directly into the amp 12v terminals. Voltage drops are heavily related to woofer movements and the struggles your amp faces from impedance changes.

Like if your woofer unloads playing 25 hz below the tuning of a ported box and is over xmax or high xmax just flopping around, that can be like jackhammering your amp with large impedance changes over and over, and you may see wild fluctuations in dc voltage. When I design walls or certain high powered systems, I tend to find out the electrical situation before I even start designing, because the nature of the box needs to match the strength of the electrical system, so that the electrical system can properly control the woofers at full volume. It’s just like higher quality amps will allow you to play further away from tuning frequency with ported, where lower quality amps wouldn’t be able to keep the woofer under control, electrically.

So, there’s lots of reasons. You just have to understand what you’re aiming for and what you truly want out of your system.
 

Buck

Why so Sirius?
5,000+ posts
10+ year member
May 19, 2008
28,416
1,144
And you’re more likely to run into problems with .5 ohm playing a wide range of music vs a competitor who’s playing a narrow frequency range. Music is hard on amps, especially when you’re a bass head lol. Gotta keep your amps juiced up and the woofers under control by all means, if you want like top tier bass or louder than what you have now bass.
 

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Similar threads

Latest threads

Latest posts

Latest classifieds