Its not very often that I get to compare two different series Digital Designs Subwoofers in the same enclosure yet alone two different 21″ Subwoofers! So when I was asked to do a comparison of the DD-9921 & DD-Z21 (Knowing this meant I got to daily ABTEC1 for some time.) I already knew I couldn’t say no to this!
Ok, to start off I have to say that comparing any Subwoofer in the Digital Designs range to a DD-Z is just unfair in my opinion as the DD-Z’s have a very unique clean sound about them. So after the DD-9921 had been removed I drove ABTEC1 around with no bass for two days while Ashley reconed the DD-Z12 into the DD-Z21 that it is today.
As soon as the glue had set we all went and had a quick listen to the Z21 at a low level but at this point I could not tell the difference between the DD-9921 and the DD-Z21 due to volume being very low. I can tell you that the rest of the day felt like an eternity since I was itching to get some run-in time on the DD-Z21!
The first three hours of run in time was spent at Petone Beach playing songs with bass in the mid 40-30Hz range with the volume at eight (I demo with the volume at 13-15) on the Head-Unit, this was enough to get the DD-Z21 moving for its initial run in period and also loud enough to be able to tell that distinctive DD-Z clarity & responsiveness that the DD-Z are known for!
At this stage I could already tell the DD-Z21 was more dominating at lower levels than the DD-9921 was at a similar run-in time, don’t get me wrong the DD-9921 is a brutal Subwoofer that is insanely quick for a 21 but the DD-Z21 is so much more responsive and I think the Neo-Magnets have a lot to do with this.
For the next day ABTEC1 was parked up in the ABTEC Workshop on a charger playing my 30Hz and higher USB all day and night until it became too overwhelming for the guys working in the workshop. Even though it wasn’t that loud inside ABTEC1 when you walked over the other side of the workshop it became very apparent the bass from a 21″ Subwoofer travels a good distance even when a vehicle is all sealed up.
Now for the next nine hours of run-in time I can not comment on since Ashley was driving ABTEC1 up to Auckland while I worked and caught a cushy plane flight afterwards.
During the V 4 & Rotary Sounds Alive & Extreme Bass Battle Sound Off we left ABTEC1 playing (At volume 10 now) for a solid nine hours with some quick minute bursts at twelve on the volume. During these demo’s I noticed the DD-Z21 to now be on par (Volume wise) with the fully run in DD-9921 but the real difference was when I decided to demo some progressive death metal, not many 15’s or 18’s can keep up with the double kicks so when the DD-Z21 was hitting every little kick I soon realised that it hits so much more precise compared to the DD-9921 in these fast transitions!
The DD-Z21 has finally hit over the fifty hour mark and on most Subwoofers you would of classed this as run-in but since the DD-Z21 has the Extra-Stiff Suspension the full run-in time can take months, but over the next months I will upping the power until it reaches the optimum power the DD-M4 can put out!
Now the hard part, the comparison. To be honest there is no way to compare a DD-9921 to a DD-Z21 after spending a good amount of time running both in the same car/enclosure, apart from both of them having a carbon fibre cone/dustcap and the same basket/Erom surround. What I can say is the DD-Z21 not only hits harder, faster but it does so while sounding cleaner too.
A lot of the NZ Bass Community now know my plans on running two 21″ Subwoofers in my up and coming build and as much as I would love to run two DD-Z21’s I’m going to have to settle with two DD-9921’s instead, my only reason for this is the time I’ve allocated for my savings/spending and due to this my plan is to have my build done by next Christmas… In saying that, if I do find the money in the next few months I will be changing the build for the DD-Z21 without a doubt!