Hertz HDP Amps
 

Recently HERTZ came out with a new line of amps. (HERTZ HDP amps). I am interested in your comments on the sound quality and ease of tuning if you have installed one of these amps.

I would think Hertz along with the other high end brands would be great. What are you thinking of powering with them?

Sound System
 

I already have Focal K2P speakers for the fronts that need 70RMS to power them. The HERTZ amp supposedly smooths out the highs well.

Any suggestions on a sub located in the rear area covered by the foam piece in front of the spare tire well is appreciated. I like this location since it would not required removal of anything. I thinking a pair of 6" or 8" subs located either side of a small footprint amp side firing that would be installed in a ported sub box primarly for a hidden look. For the music I listen to, I do not need a massive amount of bass.

How did you like the JBL MS-8 processor? It is my understanding that I is easy to tune, but has it limitations due to the out-of-the-boxd tuning that comes programmed with it. From the comments on the DIY web site, this processor suppossedly sounds best with a center speaker; not sure why. I do have a set of Alpine 6117 speakers with a small footprint that could be used for a center speaker if need be. Any thoughts?

The focals can take a lot more power than 70 as long as the amp is producing a clean signal. I have likes and dislikes about the JBL ms-8, for one yes it is easy to tune as long as you know about octs. and crossover freq. However it is limited only but eh 2 volt output which IMO is very poor and low and I would have liked to have seen 4 volt out. However if you are worried about the harshens of your tweeters you should know that the ms-8 is pretty much made to go active and you can easily smooth them out if you know what you are doing.

Sounds great without a center and that is the only way I would run a system. Subs is up to you and where you want to place them and what your looking for as far as bass. I know the ms-8 calibrated the sub as well. I would also say that if your looking to control your sub or use the head units EQ your not going to be able to. The ms-8 pretty much ignores all of that.

Hertz and Audison are the same brand. Audison amps are very good. Some models can run in Class-A depending on module selection; which makes them sound great for mids and highs. They run hot however by design due to their Bi-Polar output stage (instead of mosfet) with a higher voltage bias (Making them sound warm; class-A) and are not the best for powerful subwoofers.

For the win, the only other amps in this category are old SoundStream Class-A, MCx, and some Reference/Rubicon amps built in the US back in the early 90s, and similar amps using TIP101/107 output devices. I think the old SoundStream stuff is still probably better, but Audison amps are very good and easier to get - new stuff. Is the Hertz amp in the same as the Audison line?

I have an old Soundstream Reference 1000sx which I will sell for $300 shipped. Works flawless and one of the best sounding mass-produced amps ever.

Woops, I just looked at the hertz HDP on their site. Sorry but its a Class-D amp. It may work for you but you may have a lot of harshness in the upper frequencies due to the over-all maturity of Class-D amps. If you want a Class-D amp for mids and highs, try ZedAudio as they are the absolute pioneers.

Contracry to what I said before, Hertz HDP amps are probably better for mids and lows and probably not high frequency. If you want a 'Hertz' amp that works very well for highs, look at their Audison line, or look at a Class-AB line from Hertz.

Hertz and audison are built the almsot the same but there not the same company.

You are right. Audison is the parent company for Hertz. Their amp design are stil similar though, as most car audio companies have amps which are clones for other companies, IE - MaxxSonics

HERTZ Amps
 

I likely will choose a class-D amp for its ability to stay cooler since I plan to located it in the rear hatch area where the foam piece is located. I will let you know what I find out after someone has installed a HERTZ HDP amp ASAP.

I will check out ZedAudio amps.

I live in GA, you in FL. I imaging things may be a bit hotter in FL depending on where, but Atlanta has been hotter than Tampa according to some recent visitors of mine. Although they run hot, my SS Class-A Reference and Reference 1000sx do not run hot enough to go into protection. You should be fine with most amps in the compartment below the foam, especially an amp for just door speakers.

Also, my friend has a DBDrive 1600 amp which I repaired for him. It's class-D, and actually runs hotter than my SS 1000sx which is class-ab. Class-d is not all that it is cracked up to be in some cases and depends a lot upon construction, design, sync material, and driving loads. In my experience repairing amps this has come more apparent, and the irrelevance both widened and narrowed between the differences of Class-AB and Class-D. Class-D has a lot of hype and not a whole lot of real good amps using it correctly. I've seen maying using components designed for AC/DC motors and not for Audio.

Yes, Zed makes great amps. I'm glad to see they are making them again as they were the original pioneer car-amp designers of the 70s-90s. They built the first 2x200w amp for cars and called it a very early series Hifonics Zeus.

OR run fans. A install I did in WV using a audison LRX 5.1 is covered with the stock floor and does run hot but its ok as long as you circulate air.

Amp Brands
 

I looked at ZED Audio Draconici ii amp. Its a 4-channel amp that should work with a set of focal K2P for the fronts a couple of small subs I plan to locate in the rear hatch area where the foam piece is located in front of the spare tire well. This amp can be bridged front and rear as I understand. Do you have any experience with this amp?

I have not looked at or seen anything Zed in person except a Nakamichi design just a few years old - It was a pretty small amp that some moron shorted out pretty good, and I was extatic when I saw Zed designed it. I do currently repair some of their old Hifonics, Rodek, AutoTek, Crunch, Nakamichi (when they were excelent) and ESX amps, and even though they are that old there is not too much on the market which could compete from that era. There are boasted claims that the new stuff is even better.

I think you should really read everything on zed's website, because he is considered a revolutionist who designed amps for most of the old-school audio companies. Now-a-days, everything is made in China and is so cheap and copied that most companies cannot afford to use Zed for the designs. If you call, you may even be able to talk to Steve Mantz himself, give him your situation and he will set you in the right direction. Back in the day, everything Zed made was competition class - for both high SPL and the best SQL. Today, I think he stands by the technology, and claims that the new stuff is more-or-less a no holds bar compared to the stuff he designed and mades many years ago. If should all be very good, top notch products built in the USA.

I've fixed hundreds of amplifiers to date, and would be absolutely jelous of you if you bought anything built by ZedAudio. I really hope it works out!

One more thing, you may want you can pay a little extra for the BurrBrown option. If you are insane and want nothing but the best in terms of warmth, character, low distorion, and high SQL amplification - BurrBrown is the best in the entire industry. I dont think any other car audio company can offer this better than Zed. You might have to call and ask him about this option. I think it adds about $100 to the cost.

I would say that is an opinion not a fact.

With so many great names out there it is like home audio everyone has a preference to what they think is the best.

McIntosh
Sinfoni
Brax
Zapco
Butler
Audison

And older US amps come to mine when I think best of the best

Amp Options
 

Almost purchased a Brax amp. What I didn't care for was the size. I will check out Sinfoni, Butler, and Zapco amps. The amp size must have a small footprint.

I will likely need to bridge the rear for two small (6-8") subs I plan to located in the rear hatch where the foam piece is locate. I am looking into a Audison Bit Ten (it's a smaller version of the Bit-One with only 5-channels instead of 8-channels) for its tuning aspect sometime down the road.

Do you have any experience with any of the suggested amps and a Bit-Ten?

The audison and zapco I have the bit-ten never heard of that one.

Bit-Ten
 

A bit-ten is a tuning signal processor (not an amp) similar to the Bit-One manufactured by Audison. :tup:

Got ya

Burrbrown is now a division of texas instruments, and that division of ti is simply the best in terms of audiophonic IC construstion. BB is the intustry standard for operational amplifie circuits in terms of their entire line of parts and such. Many repair techs will pay the 30x premium for BB over other opAmps made in China or even from Texas Instruments. BurrBrown components can mainly only be found in the highest of the high audio equipment mainly in home audio, but is also the primary device used by engineers in their reference designs. Often times stumped by Acountants who prefer cheaper parts for making higher profits.

you can pay someone to upgrade most amps and processors with BB parts but the cost is usually not worth the trouble.

as far as I know for car audio BurrBrown is found in Zed factory upgraded amps and not many others.

Zed Audio amps
 

I will have to check the Burrbrown (BB) options from ZedAudio. I know it was an option in the past. What's the longivity of the BB componets?

They dont un-necesarrily burn out. Any good quality built amp should last for years and years as long as its hooked up and tuned properly. I'm sure amy amp in the category you are looking after will have longevity. The difference between BB and using generic branded ICs is the quality of build in how it relates to the quality of sound. Only some of the elitist of audiophiles ask for them by name. If you get BB parts you should be able to tell when the music is completely silent (no hissing on a blank track unless induced by head-unit or processor), and warmth/depth/fidelity/control at the highest of volumes.


For my repairs, I can pay $0.75 per opAmp for the TI or chinese equivalent, or spring for the BurrBrown parts which can run up to $20 a piece. Most amps have several to dozens of these parts.

Here is a good read on opAmps. BTW, the opAmp is the the first device in-line with any amplifier's pre-amp circuitry. If its a piece of junk (I've seen many in Amps which were never intended for Audio) then its probably not going to make the rest of the amp sound good.

http://tangentsoft.net/audio/opamps.html

Opamp: Burr-Brown option on Zed Audio amp
 

I will check out the Burr-Brown option for a ZedAudio amp and post back.

Here is another sick amp!!

:: Ground Zero :: Amplifier / GZPA Reference 4

ZEDAudio amps
 

ZedAudio does not have the Burr-Brown option anymore. According to Stehphan (ZEDAudio) The chips in the current amps are similar to the Burr-Brown chips.

Have you decided where you want to install the amp?
It helps to know what to shop for size wise.

As for Hertz and Audioson... Parent company is Ellettromedia.

They are Italian owned and manufactured.

Hertz HDP amps seem to be built solid. They were going after JL HD class business. and they wanted to be lesser priced then the JL amps. They have achived their goal.

Amp Location
 

I'm likely installing an amp in the rear hatch where the foam piece is located in front of the spare tire.

How does the Hertz amps compare with the JL HD amps?

I haven't done an A and B comparison. we will be putting one on the demo board soon, we will be able to evaluate soon. Of course I would rather have it in a car.

I would say hertz amps would be better than JL. Keep in min JL is a lot more hype and way over priced for their products.

Amp Demo Comparison
 

Look foreward to the JL Audio HD vs Hertz amp comparison.:tup:

OP for tons of info on amps, as well as reviews and comparisons of all the various brands and models folks are listing, cruise over to DIYMA.com - Scientific Car Audio - Truth in Sound Quality and do some poking around. a bit of research there should answer all your questions.

i've got arc audio amps in my car for their low profile.

Im over there on that site TONS of info I x2 it.