My Dream System

[jperls]

Hi everyone,

So I love the system that I have...but I have always had a dream system that would involve a home build. It would consist of the following:

Speakers (yes these are car speakers...but I know them very well and loved how they sounded in my car):
1. Hertz ML 1650.3 Legend 6.5in woofer (250 watts at 4 ohms)
2. Hertz ML 700.3 Legend 3in midrange (100 watts at 4 ohms)
3. Hertz ML 280.3 Legend 1.38 tweeter (180 watts at 4 ohms)
4. SVS SB1000 (just need one as I would use the one I already have so I would have two subs)

Digital Signal Processor - I am having a little trouble here as I want to go all active with this system...in my car I had a Zapco DSP which was amazing (still have it and the JL audio amp that I used...but that was a 5-way system...we are going for an 8-way system here). I was looking at the mini-DSP Flex Eight

Amplifier:
NAD C18-150DSP (not sure if this has an integrated DSP in it or not just by the name...hope it does not or there is a way to bypass).

Pre-Amp...no idea

Speaker Cabinet - made out of pine plywood

Speaker Wire - 10- AWG

I am curious as to what people think of this setup and if they have any suggestions....on how I might approach this differently. Many thanks

 

[Keith_W]

Car audio drivers are engineered differently to home audio drivers. They have to tolerate worse environmental conditions (extremes of heat and cold), bumps, small enclosures, non-vertical mounting, and low voltage (hence they all have low impedance). While you can't use a home audio driver in a car, you can use a car audio driver at home ... but why would you want to? Home audio drivers do not have to compromise on their performance to deal with conditions that do not occur at home.

For DSP, you have two general options. The first is to use hardware based DSP (e.g. MiniDSP, Storm Audio, DEQX, etc). The second option is to use software based DSP, which means you need a PC, Mac, Linux, or Raspberry Pi, a DAC with as many channels as you need, and appropriate software to measure and generate filters (rePhase, Acourate, Audiolense, etc) and software to convolve the filters with music in real time (JRiver, Roon, and several specialty convolvers like Hang Loose Convolver, etc.). The advantage of the former is simplicity, the advantage of the latter is flexibility, modularity, and computing power.

Preamp: you don't need one if you use digital volume control. Some DSP solutions have the ability to include remote control if you need it.

Amplifier: it looks like you need 8 channels. You can use any amp that you fancy provided it can drive the speakers and is within your budget.

 

[jperls]

Car audio drivers are engineered differently to home audio drivers. They have to tolerate worse environmental conditions (extremes of heat and cold), bumps, small enclosures, non-vertical mounting, and low voltage (hence they all have low impedance). While you can't use a home audio driver in a car, you can use a car audio driver at home ... but why would you want to? Home audio drivers do not have to compromise on their performance to deal with conditions that do not occur at home.

For DSP, you have two general options. The first is to use hardware based DSP (e.g. MiniDSP, Storm Audio, DEQX, etc). The second option is to use software based DSP, which means you need a PC, Mac, Linux, or Raspberry Pi, a DAC with as many channels as you need, and appropriate software to measure and generate filters (rePhase, Acourate, Audiolense, etc) and software to convolve the filters with music in real time (JRiver, Roon, and several specialty convolvers like Hang Loose Convolver, etc.). The advantage of the former is simplicity, the advantage of the latter is flexibility, modularity, and computing power.

Preamp: you don't need one if you use digital volume control. Some DSP solutions have the ability to include remote control if you need it.

Amplifier: it looks like you need 8 channels. You can use any amp that you fancy provided it can drive the speakers and is within your budget.

What speakers would you suggest or where should I start looking?

 

[Keith_W]

My personal experience is with Dynaudio and Scanspeak so I would recommend them. I also know that Focal sells drivers to DIY'ers and they may be a good option. My own experience with "DIY" consists of modifying my own speakers and a rather forgettable 2 way bookshelf speaker, so I am hardly an expert. I do have some knowledge of car audio though, I built a competition winning system for my car many years ago.

I assume with your car audio experience that you know how to read Thiele-Small params and how to design an enclosure? Enclosure design for home audio is a bit different to car audio. With car audio, you stuff speakers wherever you have space and try to align them all with the crossover or DSP. With home audio, you have to consider the radiation pattern of the speaker, width and shape of the baffle, how far you are going to space your drivers apart, and so on. You probably know the importance of the frequency response, but the radiation pattern is just as important, if not more so - because the sum of reflections that arrives at your ear is usually louder than the axial frequency response itself.

I recommend you read Linkwitz (same Linkwitz of crossover fame) and have a good look at his website re: considerations for loudspeaker design. I also suggest you go to DIYAudio, which is a forum solely dedicated to DIY. ASR is a great forum, but the focus here is slightly different. There is some DIY here, but not much. You should buy a copy of The Loudspeaker Design Cookbook (currently in the 8th edition, with some input from Amir, the founder of this site). This is mandatory reading, almost a textbook that all those guys on DIYAudio expect you to know before you go there and ask questions.

Having said that, I (and I think a lot of us here on ASR) would love to hear of your progress so please don't go to DIYAudio and disappear. Make sure to report back!

 

[jperls]

My personal experience is with Dynaudio and Scanspeak so I would recommend them. I also know that Focal sells drivers to DIY'ers and they may be a good option. My own experience with "DIY" consists of modifying my own speakers and a rather forgettable 2 way bookshelf speaker, so I am hardly an expert. I do have some knowledge of car audio though, I built a competition winning system for my car many years ago.

I assume with your car audio experience that you know how to read Thiele-Small params and how to design an enclosure? Enclosure design for home audio is a bit different to car audio. With car audio, you stuff speakers wherever you have space and try to align them all with the crossover or DSP. With home audio, you have to consider the radiation pattern of the speaker, width and shape of the baffle, how far you are going to space your drivers apart, and so on. You probably know the importance of the frequency response, but the radiation pattern is just as important, if not more so - because the sum of reflections that arrives at your ear is usually louder than the axial frequency response itself.

I recommend you read Linkwitz (same Linkwitz of crossover fame) and have a good look at his website re: considerations for loudspeaker design. I also suggest you go to DIYAudio, which is a forum solely dedicated to DIY. ASR is a great forum, but the focus here is slightly different. There is some DIY here, but not much. You should buy a copy of The Loudspeaker Design Cookbook (currently in the 8th edition, with some input from Amir, the founder of this site). This is mandatory reading, almost a textbook that all those guys on DIYAudio expect you to know before you go there and ask questions.

Having said that, I (and I think a lot of us here on ASR) would love to hear of your progress so please don't go to DIYAudio and disappear. Make sure to report back!

So what I am trying to do is mimic the system I had in my car because that sounded fabulous (had a good friend who had a $60k system at his home listen to my system in my car and he said it was "outstanding"...couldn't believe that quality, resolution, and clarity were even possible in a car) even though it was just the Hertz MPK lineup and I am looking at the "legend" lineup. The music just seemed to envelope you (heck you played Pavorotti concert and you felt like you were in the concert hall with everyone listening to him)...and this was with the speakers in an off-axis position and time alignment...I can only imagine what this setup could do on-axis and without having to deal with road noise/engine noise, and just the room.

THat being all said, what I really loved was how well I was able to tune the system to the car utilizing the Zapco DSP...each speaker had a 32 band parametric equalizer and I would love to have that adjustability again. The hope is to make everything active. The only real "build" portion would be the enclosure (though I am thinking about actually going infinite baffle to mimic the parameters that were in the car...also going infinite baffle means I don't have to deal with the resonance of the sealed/ported enclosure). The biggest hurdle I am facing right now...is saving up the money to build this system (probably going to cost 10k all in). As a reminder, I am in an apartment right now..so maybe this is a couple of years down the road...want to save up to buy a house first where I can have a dedicated listening room. Thoughts?

 

[kemmler3D]

So what I am trying to do is mimic the system I had in my car because that sounded fabulous...

In a car you have a few advantages that you won't have in-room that you should think about before selecting drivers.

1) You're pretty much always nearfield so the dispersion characteristics of the drivers don't matter as much.
2) Reflected sound, for the same reason and with the same result, is also much different.
3) You can get more bass in a car because the enclosed space is much smaller.

Because of 1 & 2 you can do a lot better with EQ than you can in a room, since screwing up the off-axis sound can be less harmful.

Because of #3, your selection of woofer and midwoofer would tend to be different for an in-room setup.

In other words, if you use the same drivers for in-room speakers, you will tend to get very different results, even if you do infinite baffle.

I think it's a valid goal to try to replicate the car sound, but you'll need to go a bit deeper than just putting car speakers in speaker boxes. Do you have spins (frequency response at different angles) for the car drivers you mentioned? More importantly do you have any REW measurements from inside your car? That would be a good starting point for figuring out how to get a similar sound in a different location.

 

[jperls]

In a car you have a few advantages that you won't have in-room that you should think about before selecting drivers.

1) You're pretty much always nearfield so the dispersion characteristics of the drivers don't matter as much.
2) Reflected sound, for the same reason and with the same result, is also much different.
3) You can get more bass in a car because the enclosed space is much smaller.

Because of 1 & 2 you can do a lot better with EQ than you can in a room, since screwing up the off-axis sound can be less harmful.

Because of #3, your selection of woofer and midwoofer would tend to be different for an in-room setup.

In other words, if you use the same drivers for in-room speakers, you will tend to get very different results, even if you do infinite baffle.

I think it's a valid goal to try to replicate the car sound, but you'll need to go a bit deeper than just putting car speakers in speaker boxes. Do you have spins (frequency response at different angles) for the car drivers you mentioned? More importantly do you have any REW measurements from inside your car? That would be a good starting point for figuring out how to get a similar sound in a different location.

I still have the DSP and the amplifier used in the car (totaled it last may unfortunately...really miss that Mustang)...and the DSP should still have the old EQ file used...based on that I can re-create the REW measurements...now this being all said, the current system I have is pretty great (Elac Debut Refernce, Yamaha A-S501, Schiit Modius dac, Yamaha S303 CD player...though I just ordered the Denefrips Ares II/Enyo Dac that has the upgraded Ares 12th firmware)...but I am looking at a three-way system mainly to allow a little more clarity all around (specific drivers for specific ranges in specified field...high, mid, low). I will consider other drivers...but am going to have to do a lot of research before settling in one a set.

 

[Galliardist]

As you have a good system already, you are in a position to take time for learning before starting on this project. I'd make a couple of suggestions:

1. Add Toole's book to your reading list
2. Take time to find out what makes a system "clearer", and to listen to some three way speakers to see if they are a requirement to do that:
3. Stop buying source electronics for your existing system for a bit (the Denafrips is an OK DAC and scratches an audiophile itch, but does it sound different really?)
4. Consider buying a pair of subs, and as an exercise, compare crossing them high positioned next to the speakers against crossing them low and using other recommended locations for bass management: you can also incorporate learning to measure into this.

Regarding the NAD, it has DSP and is designed for multi room setups rather than powering active speakers. I suspect it's not what you need.

It was pointed out to me in another thread by @Tangband:

Two 2 channel Tpa3255 boards for two 2-way active speakers - 60 dollars , digital crossover card (sigma studio ) - 25 dollars - two power supplies = 50 dollars - Done !

Good passive crossover components are much more expensive than 25 bucks.

You'd need a third amp board, but this approach may well pay off for you, at least as a starting point.

 

[Keith_W]

I still have the DSP and the amplifier used in the car (totaled it last may unfortunately...really miss that Mustang)...and the DSP should still have the old EQ file used...based on that I can re-create the REW measurements...now this being all said, the current system I have is pretty great (Elac Debut Refernce, Yamaha A-S501, Schiit Modius dac, Yamaha S303 CD player...though I just ordered the Denefrips Ares II/Enyo Dac that has the upgraded Ares 12th firmware)...but I am looking at a three-way system mainly to allow a little more clarity all around (specific drivers for specific ranges in specified field...high, mid, low). I will consider other drivers...but am going to have to do a lot of research before settling in one a set.

You have this speaker? It is superb! You have really set your bar pretty high if you want to DIY a better speaker than that.

 

[jperls]

You have this speaker? It is superb! You have really set your bar pretty high if you want to DIY a better speaker than that.

Yes this is the one I have...coupled with an SVS SB1000 subwoodfer...here is my thread https://www.audiosciencereview.com/forum/index.php?threads/new-to-the-hobby-question.44284/

 

[kemmler3D]

IMO you are better off trying to EQ your ELAC speakers to sound like your car system did, than trying to build 3-way floorstanders that sound like a car system. The interaction of the room / car cabin and speakers is too significant to expect similar results if you take the car speakers out of the car.

 

[jperls]

IMO you are better off trying to EQ your ELAC speakers to sound like your car system did, than trying to build 3-way floorstanders that sound like a car system. The interaction of the room / car cabin and speakers is too significant to expect similar results if you take the car speakers out of the car.

Forgot to mention this would be a bookshelf speaker (at least I think)...again this is a LONG way off (need to get out of the apartment and into a house where I can properly treat the room.

 

[D!sco]

To reach the output your car setup hits in-room, you’re going to need a room the size of your car with the same driver arrangement, or you need to pick new drivers for the tasks associated with a larger room. More subs make a huge difference, but I suspect you’ll appreciate large cone areas in the midbass drivers and wide dispersion from the mid and treble. SPL and tone tends to be the name of the game in car audio IIRC. You’ll probably be more interested in having a quality “in-room response” rather than a perfect listening window in far field. What makes car audio cool is the range of sounds that energize the “room” (cabin). Sound engineers stack piles of woofers to achieve this effect at live shows, but we can afford to replicate it in a car without much trouble.

Way out of left field, but you should check out Perry Marshall’s Bitches Brew OB speaker. Pro audio, coaxial, wide dispersion front AND rear, easy to make. It has a deafening dynamic range, and it’s easy to power. Some of the techniques and materials may interest you anyways and go a long way to demonstrating how different in-room speakers are to car audio.

Good luck!