If it matters at all, this is my passive crossover diagram.

 

IIRC, a passive XO reduces power output through it by approximately 5% per order of slope around the XO point only.

Thats its job, right??

1dB is the accepted value for the smallest change in volume that is audible by the human ear/brain.

Doubling the power of your amplifier (a 100% increase ...say going from 50watts to 100 watts) will yield a 3dB gain in volume, which is a slight gain that you can hear, though barely.

In order to double the actual volume of your music, you will have to increase the amplifier power by 10x (a 1000% increase ... going from 50watts to 500 watts ).

So that said, while there are definite advantages to going active over using a passive crossover, volume is NOT one of them--

There is a diyma thread from a few years back on this same subject...I'll see if I can find it... but it also turned into a ****show...which is not really much of a surprise

 

Short answer: Not enough to worry about.

Smart azz answer: Why are you using passives in 2023?

Old School answer: Passives on subwoofers cost about 2-3dB (yes, it was a thing)

Actual answer: When you go active with DSP you will have access to slopes that just don't make sense in the world of passive crossovers, you'll have the ability to tune out phase issues, and you'll be able to achieve the actual acoustical crossovers you want to hit - all of which could definitely add up to more potential output, if that's your primary goal.

 

Won't make much difference you'll hear, but phase aligning the midbass while technically not putting any more energy into the cabin by aligning the waveform it'll sound slightly louder.

 

I have read several times on here about how passive crossovers waste significant energy. I'm curious to learn how significant this waste of energy really is... more specifically, when I go active, how much will I gain in volume? My logic tells me that all drivers would benefit by severely limiting the frequency range that each channel is amplifying. However, my logic also tells me that this may not be very significant, since the higher the frequency gets the less energy it requires to amplify.

I am going to use my front stage as an example:

I have a passive 3-way front. I have 100 RMS per side. I use a 100 Hz 24 db high pass from my head unit.

Inside the passives, the midbass is low-passed @ 1200 Hz 12 db. The mid is band-passed @ 6 db @ 1300 and 4250. The tweeter is high-passed @ 4700 12 db. Also, the tweeter pathway goes thru a resistor, which I have selected on the middle setting.

Out of curiosity, is it possible to estimate the amount of power that I am losing by using the passive crossovers? Also, how much power is the mid receiving (estimated) with the pass-band I have?

Eventually, when I upgrade to a fully active setup, will I notice a volume increase? How much (in db)?

In the future, I'm considering getting a Helix M Four DSP, which would give me another 4 x 100 in addition to the 4 x 100 I already have. I'm thinking that I will use the Helix to power my 3" mids and tweeters, with my reasoning being the Helix is likely a higher quality amplifier than my blackbrick 100.4. Then I'll use the blackbrick for my 6.5s up front and for my rears.

None from simply switching between passive and active. The difference is barely measurable with equipment in a clinical environment.

My current setup is channel limited and I have a choice between running my fronts active with the rears bandpassed and attenuated through amp crossovers or running the fronts passive and the rear active and time delayed in the DSP.

In switching between the 2 setups the difference in the front stage was not worth what was lost with the rears. (Morel Tempo Ultra 692 MkII which have very nice passive xovers.) But YMMV depending on the quality, accuracy and composition of the passive xovers used.

As was previously mentioned the biggest gains come from being able to get everything phase matched for the cohesive attack from the initial wavefront and preserving the original production value of the recording.

 

Insertion loss is mostly from inductors with a ferrite core, most low insertion air core inductors have virtually unmeasurable losses.

capacitors have hysteresis distortion from electrolytic film, the use of high AC voltage polypropylene bi polar caps will all but have no hysteresis distortion. In the passband , caps pass current almost perfectly and don’t have losses .

You want large air core inductors and polypropylene caps with at a minimum 240VAC rating , I go for the 400V solen polys.


caps being used as a path to the other side like in a 12db low pass , where the cap shorts to the negative wire , polypropylene isn’t needed as it’s a short on purpose, so you don’t hear hysteresis. Caps in series on one of the wires you do want poly

 

In a good passive crossover, the resistors are the only thing significantly reducing output, and they are typically used to attenuated the high frequency drivers, specifically tweeters. You don't really lose any noticeable output from them, unless you use the attenuation adjustment on your tweeters, but in that case it's intentional to balance the output with the other speakers.

 

Insertion loss is mostly from inductors with a ferrite core, most low insertion air core inductors have virtually unmeasurable losses.

capacitors have hysteresis distortion from electrolytic film, the use of high AC voltage polypropylene bi polar caps will all but have no hysteresis distortion. In the passband , caps pass current almost perfectly and don’t have losses .

You want large air core inductors and polypropylene caps with at a minimum 240VAC rating , I go for the 400V solen polys.


caps being used as a path to the other side like in a 12db low pass , where the cap shorts to the negative wire , polypropylene isn’t needed as it’s a short on purpose, so you don’t hear hysteresis. Caps in series on one of the wires you do want poly

Dam...I didn't know ANY of that...

"capacitive hysteresis distortion" definitely sounds like something you do NOT want to hear in any sort of medical setting

Eventually, when I upgrade to a fully active setup, will I notice a volume increase?

That said, is the answer to OP's question yes, no or maybe...me thinks that you are going to say maybe??

 

Dam...I didn't know ANY of that...

"capacitive hysteresis distortion" definitely sounds like something you do NOT want to hear in any sort of medical setting



That said, is the answer to OP's question yes, no or maybe...me thinks that you are going to say maybe??

You know it’s a maybe , lol 😂 some yes , I’ve read up to 5% but I’ve also heard with high quality components it’s negligible

 

Thanks for the answers. It was just to satisfy my curiosity! I'm not unhappy with my setup by any means... in fact I'm quite impressed by it every time I get in my car considering I've spent ~$1000 on it!

With that said, the only logical next step is to upgrade to a DSP/amp. I'm not in a hurry, as it's an expensive (to me) expenditure, but if I have my way (and can maybe find a good used one like @ItsonlyaHONDA did for $450), I'm thinking my best bet is to get a Helix M Four DSP.

The problem is this: I also need to purchase a laptop and a UMIK-1/UMM-6 mic in order to be able to connect to the DSP, as Helix does not offer an Android app, and I need one of those 2 mics in order to fully utilize the DSP.

If you guys have seen my other threads, I have considered buying an imm-6 with apple USB-C adapter to use on my Pixel 6 with AudioTool, but I've decided against that. It's only $30-40 more to buy a proper USB mic.

Also, I've considered DSPs or DSP/amps that have an android app, but this is obviously a situation where a laptop is needed. I've had some situations lately where I've needed to use word/excel and it was miserable trying to do so on a phone. Sure, it's possible, but it's annoying enough to download a PDF manual to read on a phone.

It would be highly antagonizing to try and use my phone to setup a DSP, especially when I also generally use my phone thru Bluetooth as my source to my head unit! Tuning the DSP would take forever!! And the results will not be as good since I can't use AudioTool like REW.

I have sources for laptops back in Indianapolis, as I worked in the computer industry for many years prior to coming to Santa Cruz, CA. Part of the reason I have not already bought one is bc I live in a sober living house with 19 other people, so I don't have a super secure place to store it. Also, I park my car in the street, and we have had 2 people's cars broken into in the past couple weeks. They had tools stolen. I do have 5% tint around the back of my vehicle partially bc I don't want thieves to see my system and jack me. This is also part of the reason why I didn't buy expensive gear.

I have not had any issues at the house, but I also currently do not have anything really of value in my area, and I like to keep it that way so I don't have to worry about it. I've learned in the past that people see what you have, then tell somebody else about it, and then pretty soon it magically disappears.

 

There's one for 500$ here

https://www.diymobileaudio.com/threads/parting-my-system-out.463687/#post-6210346

 

It's a misconception that a microphone is required. Sure, it's a very valuable tool, makes life much easier, but it's not absolutely necessary. A tape measure to get the TA close before tweaking it by ear helps. Your ears are all that's absolutely required. Don't let perfect get in the way of good enough... TA with a tape measure by itself is worth the price of admission. EQ is just icing on the cake...

 

Your point is understood, but the mic is the single cheapest part of this upgrade path. If I buy a DSP, I want to be able to utilize to it's maximum potential.

Also, my head unit has time alignment... I'm just limited to using it to set it to the midbasses on my 3-way passive front in .07' increments. It also has the feature to set gain in 1 db increments for each corner. So I've used all of the available features to their fullest extent. I'm pretty happy with the result and I enjoy it everyday to and from work.

I like to tinker with things, however, and I would like to have a full-on setup. I'm not thrilled about having to spend $700-800 total to accomplish this, especially when I've spent $1000 so far. That's nearly doubling the cost of my system.

I've asked a couple people what their estimate was as to the percent of people with an upgraded stereo who are active/DSP and we all thought that it's like 5%.

 

I'm pretty happy with the result and I enjoy it everyday to and from work.

That's all that matters...

I've asked a couple people what their estimate was as to the percent of people with an upgraded stereo who are active/DSP and we all thought that it's like 5%.

I'm sure it's much, much lower than that... My local shop told me I was the only person in the area interested in SQ; everyone else just wants thump.

 

My local shop told me I was the only person in the area interested in SQ; everyone else just wants thump.

I literally don't know a single other person, IRL, who is remotely interested in building an SQ system.

It seems that bluetooth speakers and lifestyle systems are the benchmark sound these days, and anything better than them is already massive diminishing returns for normal people.

So different to what it used to be.

Edit: And thump/bass systems are long dead here - if music can be heard outside your car it's classed a hooning offense, and it only takes 2 of those to lose your car and your license.

 

I change my mind on what I want to do on almost a daily basis. I wonder what percentage of overall sound quality I'm missing out on by not adding a DSP. I'm guessing maybe 20%??? Based on that it's a lot of money to pay percentage wise compared to the total cost of my system thus far.

I'm fortunate to have a very short drive to and from work, so I haven't been putting many miles on my vehicle. Considering I have 243k miles, I'm always worried in the back of my mind that something is going to break. If I had a newer vehicle with low miles, it would be much easier to justify spending more money on audio gear.

Sometimes I still want to try the Recoil DSP for $150. That's cheaper than the Sennoupu. I think it would probably work fine as long as you fed the device a 2-3v signal and don't try to get much more than that out of it. If it doesn't work well, I can always sell it, but I'm not too thrilled at the proposition of installing something to be unhappy. I've already stated this in another thread, but after buying another amp and more wire etc, it's not that much cheaper than buying a superior Helix M Four DSP used.

Overall, I'm going to wait. My job has slowed down some bc it's the off-season, so I'm not getting a full 40 hours anymore. I already work 3 different positions to keep the number of hours that I have, but the boardwalk is only open on weekends and it's limited operations. This means only half the boardwalk is open with limited rides. There are few people that still have full-time hours - in fact I get more hours than probably 95% of the employees already.

 

Get a mic , there cheap ….

 

Passive crossovers get a bad rap on this forum (and among the SQ community in general). I still think there are situations where they can be used successfully. Power consumption is not really an issue as stated above. If you have a mid and tweet pretty close together there’s no reason not to use the passives and save your amp channels for other duties.

I would totally run a passive tweeter and 3 or 4” mid, then active midbass, rear if needed, and sub.

 

Passive crossovers get a bad rap on this forum (and among the SQ community in general). I still think there are situations where they can be used successfully. Power consumption is not really an issue as stated above. If you have a mid and tweet pretty close together there’s no reason not to use the passives and save your amp channels for other duties.

I would totally run a passive tweeter and 3 or 4” mid, then active midbass, rear if needed, and sub.

I use passives all the time

 

Agreed, lots of great multi channel DSPs out there that make it easy to just go full active. However it’s good to remember what it was like to have a budget for an install that doesn’t afford something like that. You can do a log with just 4 channels of time alignment on a head unit or something like Kicker’s 4x50 watt amp for $279 that has an auto tuning DSP.

 

I am about as far from an expert on active VS passive crossovers as can be, but I recently went active with a three way in my BMW and noticed a big difference. I think being able to precisely tune and choose the exact crossovers made it,so for me it's more about the DSP than simply being active.

There, how's that for expert advice?!

 

Passive crossovers are estimated to waste around 3% to 10% of power. This loss occurs due to the inherent inefficiencies in the resistors and inductors used to filter audio signals, which dissipate some energy as heat. Although passive crossovers effectively direct frequencies to the appropriate drivers, they are generally less efficient compared to active crossovers.