I now run a PPI DCX 1000.1 running 2 IDQv3 subs. A shop in town has had this US amp MD23 sitting on the shelf for a few years now never been used and has marked it way down. Comparing the specs it seems like the US amp would be better for SQ but it is an A/B so the PPI is probably more efficient. PPI S/N 80%, US amp S/N 105%, PPI damping 50, US amp damping 600. I also like the fact that I can run my subs at 2ohms instead of 1 ohm. Anyways this is something I don't have to do but it would be nice to try something new. I don't want the US amp if it's going to drain my electrical system real bad. Any input would be greatly appreciated
I dont have much opinion on either amp but I dont think either would be totally ideal for the best SQ performance. I'd probably sway tward the USAmp or look elsewhere. Incidentally I'm more keen on the real old stuff made in the US.
After looking at the manuals for both amps, the PPI makes it's 1000 Watts at 1 Ohm load while the US Amps makes it's 1000 Watts bridged into a 4 Ohm load or 2 Ohm load in two channel mode. Both have about similar features of low pass, subsonic, bass boost, etc. but the PPI has a phase switch. In my opinion, you will probably not hear the difference between the S/N ratios, unless you are sitting right next to the subs.
Is there something specific that you are unhappy with on the current install?
I think I would recommend that keep the amp you already have, or like advice from above look at something else. Free - $.02
Is there something specific that you are unhappy with on the current install?
I think I would recommend that keep the amp you already have, or like advice from above look at something else. Free - $.02
The answer is that it depends. If you are looking for better sound you should be looking elsewhere, what is your front stage? What head unit do you have? Are you running a processor? How well tuned is your vehicle?
I really thought it would be nice to try something new.
Two things I don't like about the PPI is some of the higher bass notes don't seem to be as smooth. My other reason is stupid but when I first started putting this all together about 8yrs ago I was getting advice from someone who praised PPI so I went out and got one only to find out that they were bought out by DEI. Stupid yes. However it still is a good SQ amp and I love being able to set the Q at 30hz and pulling those low notes out. It sounds very clean at those frequencies.
I liked the idea of running the subs at 4ohms bridged on an a/b amp but I don't like that the US only has the 45hz base boost option. Again I do like the Q bass. All in all I just want to try something different but I don't think this is the right option. Just to let you know I am running CDT es comps with the upstage super tweets. Also running 4" comps in the back for rear fill. I'm running an eclipse HU 8v. CDT SQA 4100 for mids. All in a Chevy Silverado Z71 extended cab with all doors fully mated. If and when I do something different it will probably be have to be used but any idea's or other suggestions would be appreciated.
Just to let you know I am running CDT es comps with the upstage super tweets. Also running 4" comps in the back for rear fill. I'm running an eclipse HU 8v. CDT SQA 4100 for mids. All in a Chevy Silverado Z71 extended cab with all doors fully mated. If and when I do something different it will probably have to be used but any idea's or other suggestions would be appreciated.
By the way thank you for your comments I posted this in 3 other forums and you all are the only one's to respond!
Eclipse CD5000. It does have some preset time aligniment and no I am not running active.
odd seing people still running IDQ's besides myself, Ive been using two IDQ12V2's for the past 10 years and they are still sounding just as clean as ever..
Have you tried porting the idq's? Mine are in 1.35CF each, slot ported box's and they sound absolutely amazing, Without much SQ loss from sealed.
They pretty much beg to be ported.
Have you tried porting the idq's? Mine are in 1.35CF each, slot ported box's and they sound absolutely amazing, Without much SQ loss from sealed.
They pretty much beg to be ported.
For your issue with the "higher bass notes", the first thing that comes to mind is maybe the low pass crossover setting may need some slight tweeking for the subs/cabin. Just out of curiosity, what is it set at?
I assume you are running the CDT's full range off the headunit power then? This could also contibute to your symptom where the head unit is running out of gas on the midbass.
I could be wrong, but the DCX series of amps guts look like the same engineering as the Pre-DEI PPI, like some later Power Class and PCX series, so don't feel silly for buying it.
Up until just about a year ago, I had been running A/B amps for sub duty. Then I switched to D. I switched to an amp simply for the tuning features it has that cater to subwoofers and because it was designed by the old PPI engineer.
I assume you are running the CDT's full range off the headunit power then? This could also contibute to your symptom where the head unit is running out of gas on the midbass.
I could be wrong, but the DCX series of amps guts look like the same engineering as the Pre-DEI PPI, like some later Power Class and PCX series, so don't feel silly for buying it.
Up until just about a year ago, I had been running A/B amps for sub duty. Then I switched to D. I switched to an amp simply for the tuning features it has that cater to subwoofers and because it was designed by the old PPI engineer.
It's funny you should bring this up. Yes I have tried the IDQ's ported, and for 10 mins it sounded great and blew on me. ID did repair the sub but I am not happt with how the hole situation went down. Check this link out if you are interested. Car Audio Message Forum - CarStereo.com
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My crossover is set at 80hz on the head unit and the amp I think is at 88hz. My CDT's are running off a 4 channel CDT SQA 4100.
Third time is a charm, now I know what a SQA4100 is.
Sounds like this is a very nice system that needs dialed in.
Here are my opinions/suggestions. I have almost never enjoyed subwoofers in any vehicle crossed over much higher than 65Hz. And I bet your cabin gain is intense at or near your current crossover point. You may want to try it a little lower.
I have never had a HU that had an adjustable crossover on the sub line out, so another thing you may want to try is turning it off and just using the amp's crossover.
Last thing if the top two ideas don't help, you may want to adjust your high pass crossover to the CDT's slightly higher.
Sounds like this is a very nice system that needs dialed in.
Here are my opinions/suggestions. I have almost never enjoyed subwoofers in any vehicle crossed over much higher than 65Hz. And I bet your cabin gain is intense at or near your current crossover point. You may want to try it a little lower.
I have never had a HU that had an adjustable crossover on the sub line out, so another thing you may want to try is turning it off and just using the amp's crossover.
Last thing if the top two ideas don't help, you may want to adjust your high pass crossover to the CDT's slightly higher.
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I'm going to be running an arc fd 600.1 on a IDQv3 12 in a ported box. That amp has an adjustable bass boost that goes down to 30 hz. Do you run q bass or bass boost?
I would fade your speakers so you are only listening to your front speakers. Once you do this then set your time alignment. Now you should have a proper sound stage and center image it's time to tune. Turn your subs off and pull out your RTA. Set the crossover on your front stage as low as possible without bottoming out bottoming. If you can get down to 60hz or lower, all the better. Now tune your system using the RTA so that all the terrible peaks and valleys are taken care of. You don't have to get ruler flat, just tame the bad parts. Now it is time to bring the sub back in. Set your sub crossovers around 60hz or where ever you found your speakers to be able to play. Now set your time alignment on the sub. Don't be afraid to try some long distances on the time alignment, your goal is to find the perfect mating to your midbasses. Tweak the levels till their perfect and you are all set.
What is a RTA. The only alignment settings I have are pre set options like seat position, car type,tweet position etc. The HU does have the circle sorround which does do some alignnment adjustments to but it tends to increase the highs.
Nice, clean layout. You just have the cover removed from the PPI just to show us the guts and you don't run it that way right?
RTA = Real Time Analyzer.
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