Passive vs active in Scott B's words

dwnrodeo · Post by **dwnrodeo** » Thu Jun 17, 2010 6:35 am

Eric D wrote:This is now off topic, but I fail to see how an RTA does not have any use here, or anything to do with this.

I have a set of $2000 recording studio speakers. And for the record they are active, with separate internal amps (one on the tweeter, and one on the mid). I use them as specified by the manufacturer, by sitting 1 meter from them. They are about as ruler flat as you can get, until down around 80-100Hz, where the room starts to come into play. They sound great. Some of the best speakers I have ever owned. Countless others have agreed. Anyone I have had listen to them has liked them.

So what you are saying then is that if I shoot for this capability in my vehicle, it won't sound good?

We never know how a recording artist has EQed their final track. What we do know is the flatter the response the better the chance we will reproduce what the artist intended, considering they probably recorded the track on a ruler flat studio setup which they applied EQing to until they were satisfied.

If any system is not ruler flat, it is simply a guess as to what it should be. And who can determine if my guess or your guess, or the next guy's guess is closer to the "real" thing?

shawn k wrote:Eric. For this particular comparison I think you are trying to be a little too technical. I do understand where you're comming from about flat response, but don't worry about it here. Remember the a/b comparison you did the write up for between the RF and PG amps? Treat this comparison in the same manor. I don't recall you applying any measurements or readings between the two amps, just purely listening to both to come to your conclusion. This is no different. You cannot "measure" a more difined soundstage, nor can you "measure" a more natural vocal presence. This is why I always say "trust your ears" and not the specs!

Systems utilizing passive xovers can still sound great! I have not tried to hide this. But so many of these xovers do not resemble a "flat" response (even tho the system sounds great).

IMO.. a system that has been tuned for a flat RTA response sounds horrible! This is why sound off competitors often use mutlitple eq's and/or intricate processors to enable them to have independant settings ie..one for a flat RTA reading and another for SQ (subjective listening). I assure you that none of these competitors would use their (RTA) setting for the SQ portion of the competition.

So put away the RTA and give it a go.. see how it sounds.. let us know

An excellent post over at DIYMA: http://www.diymobileaudio.com/forum/diy ... ponse.html

IMO sound quality is subjective from person to person (go figure!). I know some people on here have mentioned that their 5" drivers will play flat (RTA flat) to 60 hz, and that sounds good, but will the sound be impactful at 60 hz compared to a larger diameter driver, say 8" or 10"? Are you gonna feel that kick in your chest when the bass drum hits? In my opinion, no. As for getting close to the "real" thing? All that matters is that it sounds good to you, and you get the experience you want from it. Take for example musical lyrics. People get different meanings from the song lyrics yet the words are the same.

KUB3 · Post by **KUB3** » Thu Jun 17, 2010 12:55 pm

I now use no crossovers in the voice spectrum. Point source FTW

Post by **Eric D** » Thu Jun 17, 2010 1:32 pm

To some people a flat car audio RTA curve does sound bad. But, to a lot of others it sounds incredible.

As far as the recording artist, an end user with a flat setup is going to get what the artist intended. Recording equipment is very flat (the speakers and other support equipment), the recording artist adds EQ to make the track sound as they wish (played back on flat equipment), then they record with this EQ built in. If you have a flat playback setup, you get what the artist heard in the studio. If you don't like what you hear, then you can choose to add or remove what you want with your own EQ.

If this were any other way, then the artist would have to give you a "reference curve" to RTA your setup with. That is the only way you would be able to get back to what they heard in the studio.

This is a whole different argument, but for those of you who think flat sounds bad, have you really ever heard a flat setup? Almost no car audio installation is flat, as the environment is so reflective, if you move your head just one inch to the side for example, you will get a very different curve. The only way you can really be sure you have a flat system to listen too is a known flat home audio setup. I have heard flat car audio setups which did sound bad. But, I am confident my head was not where the microphone was. I have however heard home setups which were very flat and they were among the best setups I have ever heard.

While at Rockford, we tested a lot of home audio equipment in our lab. We tested a lot of pro audio equipment as well. If we ran a flat setup, EVERYONE who listened to it thought it sounded excellent. However, if we put in a non flat setup, some people would like it more than the flat.

My point here is everyone I knew liked the sound of a flat system, and some of those same people liked a non flat system even more. No one thought the flat setup sounded bad.

Too bad all of us are so far apart. My home setup is just stereo (2-channel), and I have thousands of dollars into my speakers and the amplification to run them. I took the whole setup and brought it into Rockford back when I worked there. Between 60Hz and 20kHz, my home speakers are plus or minus 3db. That is VERY tight for a speaker system. Over most of the range they are plus or minus 2db. Now, my room at home is different, but it should have for the most part just affected the bass response of my system. Either way, I have had a lot of people listen to these speakers over the years (I built them in 1999-2000), and everyone was beyond impressed with how great they sound. I have had several people go on to build their own versions they liked them so much.

Post by **Eric D** » Thu Jun 17, 2010 1:35 pm

KUB3 wrote:I now use no crossovers in the voice spectrum. Point source FTW

I would love to give these a try, no crossover is better than passive, or active!

http://www.seas.no/index.php?option=com ... Itemid=188

I would only use them for home audio though, not car.

Post by **Eric D** » Thu Jun 17, 2010 1:51 pm

I just read through that excellent link from DIYMA, and need to clarify a few things.

-When it comes to EQs, I NEVER boost anything, that is my rule.
-Did I mention I never boost anything...
-I cut the peaks, and leave a bit more bass, as I really like more clean bass.

I once had an AudioControl DQX, which was a pretty powerful EQ. I screwed with it, my RTA, and my LMS for a week getting my system as ruler flat as I possibly could. It sounded like complete crap. I cannot stress just how badly this flat system sounded.

As mentioned in one post on the DIYMA thread, I had the "over EQ" problem going on. It is hard telling what issues so much use of an EQ caused.

So, my points about flat stereos are ones that start off naturally very flat, and you then use an EQ to just tweak it a bit into perfection.

Nothing beats solid speaker placement, and blending. If you get this right, going from passive crossovers to active is just icing on the cake. If you get it wrong, no amount of crossover work will make up for it.

shawn k · Post by **shawn k** » Thu Jun 17, 2010 2:19 pm

Eric D wrote:While at Rockford, we tested a lot of home audio equipment in our lab. We tested a lot of pro audio equipment as well. If we ran a flat setup, EVERYONE who listened to it thought it sounded excellent. However, if we put in a non flat setup, some people would like it more than the flat.

My point here is everyone I knew liked the sound of a flat system, and some of those same people liked a non flat system even more. No one thought the flat setup sounded bad..

Oooohhh. So that's why RF never made a good sounding speaker

LOL

jk...maybe

Though I can appreciate the whole "flat" response topic, we are getting waaaaay away from the original topic: Passive vs active. Achieving a "flat" overall response (if that is the goal) has way more to do with the design of the driver itself compared a xover that may be used for the particularr speaker system.

http://www.seas.no/index.php?option=com ... Itemid=188

^^ That's not something that looks all too pleasing to me. I've seen worse response curves, but I've seen much much better as well!

So have you installed that Audiocontrol yet???

Post by **ttocs** » Thu Jun 17, 2010 3:27 pm

the speakers sound is just as dependant on the mounting, speaker directions as well as cancellations. That is the reason they never sound the same in the store as they do in the car. Because of this I am a fan of carefull eq'ing as there are too many variables in car audio to say that the designed x-over that will make it play perfect in every car.

shawn k · Post by **shawn k** » Thu Jun 17, 2010 3:45 pm

ttocs wrote:the speakers sound is just as dependant on the mounting, speaker directions as well as cancellations. That is the reason they never sound the same in the store as they do in the car. Because of this I am a fan of carefull eq'ing as there are too many variables in car audio to say that the designed x-over that will make it play perfect in every car.

Precisely

Post by **Eric D** » Thu Jun 17, 2010 3:46 pm

I am going to try using my amp's crossover first. If I cannot get good results then I will put the 24xs in.

I have a few assumptions going forward, and I want to make sure I am on the same page as everyone else.

-I will loose output going active in my case
-I will gain detail in the music, but only as it relates to the blending of the tweeter and midrange
-Stereo separation will not be affected (as this would be the same passive or active)

Anything else I can count on changing, or staying the same?

Post by **Eric D** » Thu Jun 17, 2010 3:51 pm

ttocs wrote:the speakers sound is just as dependant on the mounting, speaker directions as well as cancellations. That is the reason they never sound the same in the store as they do in the car. Because of this I am a fan of carefull eq'ing as there are too many variables in car audio to say that the designed x-over that will make it play perfect in every car.

I also agree with this 100%.

It is partially why RF speakers sound great in a display, but sound like crap in a car. Any high end RF speaker will measure ruler flat (over its frequency response) in a display board, but will measure like junk in a car. RF speakers are designed for on axis response, not off axis (or at least they were when I worked there).

I found just the opposite to be true for Boston Acoustics. They sounded like crap in our display board, but really shone in an installation. For this reason most of Soundbuggy's employees had them in their personal installations (myself included), and we would let customers listen to our cars to sell the Bostons.

shawn k · Post by **shawn k** » Thu Jun 17, 2010 4:18 pm

Eric D wrote:I am going to try using my amp's crossover first. If I cannot get good results then I will put the 24xs in.

I have a few assumptions going forward, and I want to make sure I am on the same page as everyone else.

-I will loose output going active in my case

Probably, but it's not definite

Eric D wrote:-I will gain detail in the music, but only as it relates to the blending of the tweeter and midrange

Not necessarily. Hopefully you will gain detail throughout the spectrum and not just at the crossover point. This is due to the amplifier controlling the voice coil/s directly and not through other components (caps, coils, resistors) In addition, best case scenario you may notice better dynamics, an improved soundstage and ambience.

Eric D wrote:-Stereo separation will not be affected (as this would be the same passive or active)

Correct!

Eric D wrote:-Anything else I can count on changing, or staying the same?

If you are only going to use a 2nd order slope, be mindfull of the tweeter's output. If RF utilized a 4th order slope in the Passive it may have been for improved protection.

Try this at a moderate level. No need for concert loud here

Adjust the tweeter level to your liking and don't be afraid to swap the phasing for them as well.

Good luck

Post by **Eric D** » Thu Jun 17, 2010 4:39 pm

I will remove the light bulbs from a spare crossover I have and wire them in line with the tweeter. I have never had a tweeter protect light come on in any of my personal installs, so I don't think I will have any issue here. The bulb will just give me some piece of mind.

Post by **smgreen20** » Thu Jun 17, 2010 5:54 pm

Pay attention to how the bulb is wired. it seems to me that if it were in line (series) that the bulb will constantly be "on" and play to the peaks. In parellel it would do it too. So I'm not 100% sure how they'er wired in there to to burn the "extra/harmful" peaks.
And don't you mean you had a DQS? The DQX is just a crossover.

Post by **Eric D** » Thu Jun 17, 2010 7:06 pm

smgreen20 wrote:Pay attention to how the bulb is wired. it seems to me that if it were in line (series) that the bulb will constantly be "on" and play to the peaks. In parellel it would do it too. So I'm not 100% sure how they'er wired in there to to burn the "extra/harmful" peaks.
And don't you mean you had a DQS? The DQX is just a crossover.

Nope, it was a DQX (crossover and EQ in one)

As for the blubs, if they are wired in series, they should never come on unless something is wrong. (too much voltage, or a lot of clipping)

Post by **smgreen20** » Thu Jun 17, 2010 8:01 pm

How do you determine what voltage bulb to use as to what's to much voltage? Did you understand that?

The bulb is going to see voltage regardless, so shouldn't it light up no matter what? Or does the voltage have to be at a certain value?

shawn k · Post by **shawn k** » Thu Jun 17, 2010 8:10 pm

The bulbs will light when there's a lot of power applied. Which is a result of a lot of Voltage. This is typical when an amp clips. Simply put, if the bulb lights, you're overdriving the system. I wouldn't ever use them. Why try to pass signal through a tiny filament when some nice conductive copper will do so much better

dwnrodeo · Post by **dwnrodeo** » Fri Jun 18, 2010 3:10 am

Too bad all of us are so far apart. My home setup is just stereo (2-channel), and I have thousands of dollars into my speakers and the amplification to run them. I took the whole setup and brought it into Rockford back when I worked there. Between 60Hz and 20kHz, my home speakers are plus or minus 3db. That is VERY tight for a speaker system. Over most of the range they are plus or minus 2db. Now, my room at home is different, but it should have for the most part just affected the bass response of my system. Either way, I have had a lot of people listen to these speakers over the years (I built them in 1999-2000), and everyone was beyond impressed with how great they sound. I have had several people go on to build their own versions they liked them so much.

I'm not that far away...

Post by **Eric D** » Fri Jun 18, 2010 3:36 am

shawn k wrote:The bulbs will light when there's a lot of power applied. Which is a result of a lot of Voltage. This is typical when an amp clips. Simply put, if the bulb lights, you're overdriving the system. I wouldn't ever use them. Why try to pass signal through a tiny filament when some nice conductive copper will do so much better

I will put the bulbs in line and when I am all done with everything, if they don't light up, I will remove them. I too would prefer copper in line, but the bulb would be great to protect the tweeter in the event I have something too high off the start.

On the other hand, I have a big box of spare FNQ tweeters...

Post by **Eric D** » Fri Jun 18, 2010 3:39 am

dwnrodeo wrote:
Too bad all of us are so far apart. My home setup is just stereo (2-channel), and I have thousands of dollars into my speakers and the amplification to run them. I took the whole setup and brought it into Rockford back when I worked there. Between 60Hz and 20kHz, my home speakers are plus or minus 3db. That is VERY tight for a speaker system. Over most of the range they are plus or minus 2db. Now, my room at home is different, but it should have for the most part just affected the bass response of my system. Either way, I have had a lot of people listen to these speakers over the years (I built them in 1999-2000), and everyone was beyond impressed with how great they sound. I have had several people go on to build their own versions they liked them so much.
I'm not that far away...

True. And we have about 2 or three other members in the lower Michigan area. The guys over near Portland get together once a year, maybe it is time for the Michigan chapter of the PG "cult" (from another thread) to form?

Post by **ttocs** » Fri Jun 18, 2010 5:01 am

us midwesterners should show those west coast ho's how to do it....

shawn k · Post by **shawn k** » Fri Jun 18, 2010 5:30 am

OOOOOOOH SNAP

Post by **smgreen20** » Fri Jun 18, 2010 5:48 am

Eric D wrote:
dwnrodeo wrote:
Too bad all of us are so far apart. My home setup is just stereo (2-channel), and I have thousands of dollars into my speakers and the amplification to run them. I took the whole setup and brought it into Rockford back when I worked there. Between 60Hz and 20kHz, my home speakers are plus or minus 3db. That is VERY tight for a speaker system. Over most of the range they are plus or minus 2db. Now, my room at home is different, but it should have for the most part just affected the bass response of my system. Either way, I have had a lot of people listen to these speakers over the years (I built them in 1999-2000), and everyone was beyond impressed with how great they sound. I have had several people go on to build their own versions they liked them so much.
I'm not that far away...
True. And we have about 2 or three other members in the lower Michigan area. The guys over near Portland get together once a year, maybe it is time for the Michigan chapter of the PG "cult" (from another thread) to form?

If we met in lowen Mich or upper Ind I could do it. Elkhart, IN is about a 2 1/2 hr drive for me. So add time from that point to where we could meet.

rscecil007 · Post by **rscecil007** » Fri Jun 18, 2010 5:49 am

OHNOYOUDINT!!!!!

dwnrodeo · Post by **dwnrodeo** » Fri Jun 18, 2010 6:51 am

smgreen20 wrote:
Eric D wrote:
dwnrodeo wrote: I'm not that far away...
True. And we have about 2 or three other members in the lower Michigan area. The guys over near Portland get together once a year, maybe it is time for the Michigan chapter of the PG "cult" (from another thread) to form?
If we met in lowen Mich or upper Ind I could do it. Elkhart, IN is about a 2 1/2 hr drive for me. So add time from that point to where we could meet.

I'm down for that.

Post by **ttocs** » Fri Jun 18, 2010 8:36 am

I could not be any further away from michigan and still be in indiana and unfortunatly I can't travel with my digestive problems.