For what purpose are you rounding?

 

Rounding is unimportant, but to answer your question they would be 2 Ohm.

 

It's 3 ohms. What woofer is it? I
might have the data for it.

 

You are measuring DC resistance no impedance. It is usually slightly lower. These are likely 3 or 4 ohm impedance drivers (probably 3 ohm)

 

I believe the manufacturer likely intended them to be 2 Ohm

Not to many "old school subwoofers" were 3 Ohm to my knowledge

 

JL is the only one that comes to mind. If he's measuring resistance, likely DC, and in my experience, it's always and sometimes substantially lower than rated. Usually .3 to .5 below stated impedance. Might very well be Dual 4 ohm VC's, OP has not clarified. I think it is either a dual 4 or a single 3 - b ut again, without more info, just a guess. If we can find out the model, we can find the (IMP) and the (RE).

 

Manufacturers usually rate the impedance of the sub at the Zmin level after fs. It's usually higher than the value you get with a multimeter. You would need its impedance sweep to really tell. DC Re is also usually slightly higher than a resistance measurement with a multimeter, because the subwoofer is an inductor after all.

 

It’s a ground zero plutonium made by tc sounds. Early 2000s model. Looks to be a similar model to the eclipse ti pro.

p.

 

That's a Ground Zero sub.

Older version of this?

Ground Zero Audio Plutonium GZPW 10SQ 10″ high end SQ subwoofer (400 R

PLUTONIUM High-End Experience The products of the PLUTONIUM line are suitable for either ultimate SPL level or high-end sound quality. To achieve one of these targets, exceptional materials and technologies are applied during the development.The technical, electrical and mechanical skills of the...

toledodealerservices.com

 

Just saw the info on that post - one needs to read between the lines!

 

That’s not the same model. The frames and motor are different from current models. Also this was made in the USA. Eclipse TI pro looks to be the closest.

Currently it’s on a JL slash 1200.1v3 but it’s nowhere reaching XMax and can definitely take more power.
Im looking to Link another JL 1200.1 or just go with a zapco z3kd 3000 .

So is 2.7 = to 2ohms or 3 ohm? Or 4 ohm. A lot of different opinions so far but what’s the final verdict.

 

4 ohms - no sub will read higher at DC than it's average and no one made 3 ohm coils back then, it is not uncommon for a 4 ohm coil to read 2.7 at DC.

 

Doesn't your amp put out the same power 1.5-4 ohms ?

 

Yes it does, I stated that it needs more power so I’m looking to either linking another JL or getting a different amp that puts out more such as a zapco z3kd .
Im looking for an amp that will do 2000 to 2500 rms but wasn’t sure if I need a final load of 1 ohm or 2 ohm .

easy route is to just LINK up another slash 1200.1v3 to get a total of 2400 rms and not wonder what impedance each coil is. Thanks for everybody’s input.

 

It doesn’t matter. Is there a specific reason why you’re worried about it?

 

Is it possible you have the subsonic filter active? I would think 1200 watts would push that sumbitch a little harder.

Is the suspension really that rock hard, LoL 😂

 

But how am i going to sleep tonight...

 

lol , 😂 that was the testing phase. 8 gauge wires. I got it all soldered and cleaned up now.

 

The entire debacle of the old school Eclipse Ti subs blowing up amps was because it was rated at a higher impedance than it actually measured at. Anybody else remember that?

 

First GZ plutonium subs used textile/honeycomb cones back in 2005. No GZ sub is USA made.....somebody slaped GZ recone to that motor/basket...
usually we run those subs with GZPA1,5000D or later 1,6000D (3,5-5kW)....or a pair strapped to one sub

 

And this ☝also means that the voice coil is likely not correct for the gap which will skew the DC resistance due to the misalignment at rest as well.

 

It’s funny you’re making a statement that is untrue. If you dive deep into ground zero. They had a partnership back in the late 90’s to 2000’s with tc sounds making the drivers under the name Magma.

my sub has the motor that says ground zero plutonium GZPW stamped on it . Also has the Magma label aswell.

Here’s a little history about ground zero



A world-wide operating company

Just after a few years the German brand with American roots is already internationally renowned. In America, Ground Zero has been the leading manufacturer for subwoofers with large surrounds.

The Ground Zero brand, which is trademarked world-wide, is one of the world’s most respected names in car hifi. The best evidence is provided by comparison-tests in independent trade magazines in which the Ground Zero products have consistently placed by the winner’s circle with best ratings for price / performance, features and quality.

Story of success

1995: The company Ground Zero was founded in Frankfurt, Germany, by Karl F. Lautner and Peter Unterharnscheidt under the name of Ultimate Sound / MaGmA GmbH. From the very beginning, the company focused on distribution of outstanding car hifi products ”Made in USA“.

1997:The revolution of subwoofer construction!

In cooperation with the speaker designer Bob Carver, the American company Ground Zero developed an unprecedented subwoofer construction that was able to produce lowest bass with extreme levels in tiny enclosures. Huge, strong surrounds, oversized magnets, extremely heavy cones and more incredible construction details that have been unimaginable till then, caused a sensation in the Car Hifi scene. The current Ground Zero GmbH took over the rights of sale for these subwoofers in the European market.

1999:

The company moved to the town Egmating near Munich and got the complete trademark rights for Europe. From there on, the development of all products and service took place there. The GZ-typical subwoofer construction details were improved continuously, the product range has been completed by powerful amplifiers and high quality speaker systems.

2000:

The first subwoofers designed in Germany (GZPW 15 & GZNW 15) were able to set new sound pressure records measured by AutoHifi.

(AutoHifi 04/2000) "With these results, the Ground Zero sub should be worldwide unrivaled"

2003:

The first digital high power amplifiers developed in Germany caused a sensation - the GZPA 1.3000D is the most powerful mono amplifier on the market at that time. (Autohifi 04/2002) "...by far the most powerful mono amplifier know by the editorial staff"

In this year, the company, took over the worldwide trademark rights of the brand "Ground Zero“ and the company was renamed to ”Ground Zero GmbH“.

2004

A new voice coil type with 8 layer flat wire and 4 x 1 Ohm helped the GZPW 15XQ to become the best 15” subwoofer.(Autohifi 04/2004)

"The Ground Zero Plutonium GZPW 15XQ is the most explosive 15" woofer the editorial staff has ever seen."

2005

Ground Zero manufactured the legendary SPL woofers from Nuclear and Plutonium series. These woofers are able to provide unbelievable SPL Power ratings up to 10.000 W. Numerous world records in many classes of dB Drag competitions were set with those GZ – SPL Subwoofers. Countless awards of the specialized press followed.

2007

Due to their long achievement in subwoofer designing, Ground Zero has been voted to ”Best Brand“ at the renowned reader’s choice of the German autohifi – magazine. Even internationally, the Ground Zero Subwoofers stand in the forefront - the GZPW 15SPL is appointed to the ”European Mobile Subwoofer of the year“ by EISA.

2008

The gigantic GZPA 2.20000SPL brakes all existing power rating records.( Autohifi 03/2008) "...strongest amplifier ever tested by autohifi“ Autohifi readers choice award 2008 "High End amplifier of the year"

This year was also the hour of birth for the new enclosures. Starting from Radioactive line, all enclosures got a new, noble design with an illuminated plexiglass front.

2009

Ground Zero expands the product range with the High End Sound Quality Plutonium Reference line which impressed right away. Handmade speakers, crossovers “Made in Germany” and precious amplifiers with selected parts and noble materials persuade the international press and Sound Quality competitors.

CAR & HIFI 01/2009

"High End sound paired with enormous stability - the Reference 4 sets new standards!"

Autohifi 04/2009

"Ground Zero clearly reached the High- End- level with this amplifier."

Beside the great success of the new High End Line, the Dual Power compo system GZPC 165SX + GZPK 160K sets new records - it‘s SPL exceeds the maximum possible measurement level from autohifi.

Autohifi 04/2009

"The Ground Zero not only got the maximum score at features and workmanship, it also broke the existing level record."

2010

The most significant company maxim was, is and will remain: maximum operating safety, longevity and sound quality of the Ground Zero products in every market with every model. These are the points that make a well known and appreciated brand out of Ground Zero. The car hifi world now anxiously waits to learn what new and pleasurable audio experiences Ground Zero will bring them in the future.

2013 &2014 Ground Zero has added numerous new Distributors to its family. They include a re-entry into the US market as well as a new presence in Brazil

Ground Zero today

With more than 300 unique products in 9 lines and nearly 60 distributions worldwide

Ground Zero has became one of the leading Car Audio manufacturers in the world.

 

1995: The company Ground Zero was founded in Frankfurt, Germany, by Karl F. Lautner and Peter Unterharnscheidt under the name of Ultimate Sound / MaGmA GmbH. From the very beginning, the company focused on distribution of outstanding car hifi products ”Made in USA“.

1997:The revolution of subwoofer construction!

In cooperation with the speaker designer Bob Carver, the American company Ground Zero developed an unprecedented subwoofer construction that was able to produce lowest bass with extreme levels in tiny enclosures. Huge, strong surrounds, oversized magnets, extremely heavy cones and more incredible construction details that have been unimaginable till then, caused a sensation in the Car Hifi scene. The current Ground Zero GmbH took over the rights of sale for these subwoofers in the European market.

1999:

The company moved to the town Egmating near Munich and got the complete trademark rights for Europe. From there on, the development of all products and service took place there. The GZ-typical subwoofer construction details were improved continuously, the product range has been completed by powerful amplifiers and high quality speaker systems.

2000:

The first subwoofers designed in Germany (GZPW 15 & GZNW 15) were able to set new sound pressure records measured by AutoHifi.

(AutoHifi 04/2000) "With these results, the Ground Zero sub should be worldwide unrivaled"

 

Thanks for the history lesson. Speaking of history, the answer to your question was stated previously but you seem to have missed it...

https://www.diymobileaudio.com/threads/resistance-2-7-ohm-2ohms-or-3-ohms-voice-coil.466151/post-6246055

The amp you are using employs a RIPS power supply which means it makes rated power anywhere from 1.5 ohms to 4 ohms. So, regardless of whether you round up or down, the output will be the same.

 

I think you misread the part that this sub has much more potential than 1200rms. I was looking to purchase a larger amplifier and need to decide to go 2000 rms at 1 ohm or 2 ohm. That plays a huge role in purchasing a new amp.

alpine m240 is not 1 ohm stable but can do 2400rms at 2 ohms.

other route was to purchase a second JL 1200 and strap it for 2400 .

 

Until 2004/2005 gz was representative for TREO subwoofers for Europe, at the time they didnt have commercially avaliable own Subwoofer drivers. On 2005 they came out with Plutonium driver with honeycomb cone and canceled TREO. At the time i competed in streetB class and used TREO SSX 12.22 drivers and 4x GZPA 1.5000d amps and set first World record for GZ and break 7 year long DD dominance. GZPA.1.6000 was introduced that year at Sinsheim car audio fair.
Friends also competed in SS Wall 1-2 and they run gzpw15 and those cones didnt survive pressure… if i recollect correctly at least 12-14 drivers failed after one burp…. VCs were ok. I still have some pics … somewhere, lol. We also were beta testers for first gznw 12spl.

 

Neither, you need one able to do 2000 RMS at 4 Ohms.

Like the SALT4 that just sold for $500 in the Classifieds.

Not really because it’s a dvc and some are claiming it 2 ohm and some are saying it’s 4 ohm.

Neither, you need one able to do 2000 RMS at 4 Ohms.

Like the SALT4 that just sold for $500 in the Classifieds.

specs says 4ohm would be 1000 rms

unless I’m reading it wrong.


Sundown Audio Salt 4k Amplifier

SALT-4 DIGITAL MONOBLOCK FEATURES

• Digital Class-D Linkable Mono Block Amplifier

• Dual MOS-FET PWM Power Supply

• 1 Ohm Stable Load

• 24 dB/Octave – Variable Low Pass Filter

• 24 dB/Octave – Variable Subsonic Filter

• 9 dB/Octave – Variable Bass Boost

• 180° Variable Phase Shift

• 4 Way Protection Ciruit (Thermal, Voltage, Speaker Short, DC Offset)

• Wired Remote Control with Voltage & Temperature Display and Clipping Indicator

SPECIFICATIONS (Tested @ 14.4v)
2 ohm Linked RMS	8000W
1 ohm Mono RMS	4000W
2 ohm Mono RMS	2000W
4 ohm Mono RMS	1000W
Recommended Fuse Rating	400A
Low Pass Filter (Variable)	35Hz-250Hz
Subsonic Filter (Variable)	10Hz-50Hz
Bass Boost @ 45Hz	0-9dB
Phase Shift Control	0-180 Degrees
Input Sensitivity (+/- 5%)	6v-0.2v
Frequency Response (+/- 1dB)	10Hz-250Hz
S/N Ratio	90dB
Working Voltage	9v-15.5v
T.H.D @ 4ohms	< 0.1%
Efficiency @ 4ohms	90% <
Dimensions	22.05″ x 8.67″ x 2

 

Not really because it’s a dvc and some are claiming it 2 ohm and some are saying it’s 4 ohm.


specs says 4ohm would be 1000 rms

unless I’m reading it wrong.


Sundown Audio Salt 4k Amplifier

SALT-4 DIGITAL MONOBLOCK FEATURES

• Digital Class-D Linkable Mono Block Amplifier

• Dual MOS-FET PWM Power Supply

• 1 Ohm Stable Load

• 24 dB/Octave – Variable Low Pass Filter

• 24 dB/Octave – Variable Subsonic Filter

• 9 dB/Octave – Variable Bass Boost

• 180° Variable Phase Shift

• 4 Way Protection Ciruit (Thermal, Voltage, Speaker Short, DC Offset)

• Wired Remote Control with Voltage & Temperature Display and Clipping Indicator

SPECIFICATIONS (Tested @ 14.4v)
2 ohm Linked RMS	8000W
1 ohm Mono RMS	4000W
2 ohm Mono RMS	2000W
4 ohm Mono RMS	1000W
Recommended Fuse Rating	400A
Low Pass Filter (Variable)	35Hz-250Hz
Subsonic Filter (Variable)	10Hz-50Hz
Bass Boost @ 45Hz	0-9dB
Phase Shift Control	0-180 Degrees
Input Sensitivity (+/- 5%)	6v-0.2v
Frequency Response (+/- 1dB)	10Hz-250Hz
S/N Ratio	90dB
Working Voltage	9v-15.5v
T.H.D @ 4ohms	< 0.1%
Efficiency @ 4ohms	90% <
Dimensions	22.05″ x 8.67″ x 2

Sorry didn't realize it was DVC, so then 2000 Watts at 2 Ohms or a 2 Channel amp with 1000 Watts at 4 ohms x 2 channels.

There's no way it's a 2 ohm voice coil if the DC Resistance reading is above 2 ohms since as frequency rises so does impedance.

 

Before you put more power to it, can it handle said power without over excursion in the box?

 

 

The re is 2.85 so my harbor freight meter got 2.7 ohms

This thing gets 50mm xmax one way!!