[emtor]

As most of us know an x-over contains caps and inductors.
There is some agreement that caps and inductors should be avoided if possible due to the phase shift these tend to introduce.
Avoiding caps and inductors in a passive x-over is however not possible so why not just discard the x-over altogether?
The Hifi Cave channel on YouTube does exactly this by connecting a 15 inch driver and an 8 inch driver in parallel.

https://www.youtube.com/watch?v=85VLiXg0eYc

So, what do you all think of this?
Good or bad?

[FullRangeMan]

As most of us know an x-over contains caps and inductors.
There is some agreement that caps and inductors should be avoided if possible due to the phase shift these tend to introduce.
Avoiding caps and inductors in a passive x-over is however not possible so why not just discard the x-over altogether?
The Hifi Cave channel on YouTube does exactly this by connecting a 15 inch driver and an 8 inch driver in parallel.

https://www.youtube.com/watch?v=85VLiXg0eYc

So, what do you all think of this?
Good or bad?

For a two way system dont need xover and yet have a perfect matching audiophile sound, it is need that both woofer and Mid-treble drivers Voice Coil are identical.

At the moment Iam aware you can get the same identical VC only with the Lii Audio F-15 and his companion W-15 (apparently IMO) however Iam not 100% sure if they use the same VC, but the Lii Audio guys will be happy inform you this detail.

Some xovers use lots of inductors and caps so it will become a expensive patch to try give a coherent sound to two or three speaker set, unless you use cheap, poor sound steel core inductors and generic caps.

In this video you posted above he inform are getting good sound, so I would use a F-15 and a W-15 in serial to 16 ohms and a small SET tube amp.

OBS.:  However with the F-18 release I would not want use a woofer at all and have to do a lot of try and error with baffle shape and possible use a inductor to cut somewhere, I would be settle happy for just the F-18 fr driver in my small room IMO.
http://www.glowinthedarkaudio.com/lii-audio-f18.html

I noted in this video you posted he is not using a woofer but two FR drivers, an F-15 and an Fast-8 if I understand english well.

For a OB with the W-15 and the F-15 see this video;
https://www.youtube.com/watch?v=qnq0QzySvQs
This audiophile tested the F-15 and the FAST-15 and prefered the F-15.

[Early B.]

There are plenty of reasons 99% of speakers rely on crossovers. Anyone can attach OB drivers onto a slab of wood with no crossover, provide zero measurements, and claim it sounds good.

[Woodsage]

I’ve seen several of these builds on YouTube. I always scratch my head and wonder why a F15 full range driver and not the W15 woofer.

I just had four W15’s show up at my door yesterday. They are fantastic looking drivers, big, heavy and beautifully made.










I also ordered a pair of Silver 10 Full-range drivers but they haven’t shown up yet, they appear to be stuck in Alaska for some reason.

I’ll start by running the 10” unfettered and power the woofers actively with a Crown. Once I see how low the 10” goes and how high up I need to run the woofers I’ll most likely do a simple 2 way or 2.5 way x-over. These woofers are very efficient especially when both voice coils are run. Not sure if I’ll need two per side as planned, we’ll see.

[FullRangeMan]

With measurements the sound improve?

[emtor]

There are plenty of reasons 99% of speakers rely on crossovers.

In a conventional multi-way system a crossover is a must since the drivers have a very limited frequency range.
A bass unit would only sound bad while the tweeter would suffer from a burned out voice coil.
In this scenario two full range drivers are being used so there's no danger of ruining drivers or forcing them to operate outside of their respective frequency ranges.

[emtor]

I noted in this video you posted he is not using a woofer but two FR drivers, an F-15 and an Fast-8 if I understand english well.

Yes,-two FR drivers.

[JohnR]

I mean, it's a hobby so do what you enjoy doing.... however ifyou want to learn and get a good result I advise not taking this kind of video seriously and instead learn to measure, learn how a crossover actually works, and if you really want to "avoid phase shift" then look into DSP solutions.

[Early B.]

...if you want to learn and get a good result I advise not taking this kind of video seriously and instead learn to measure, learn how a crossover actually works, and if you really want to "avoid phase shift" then look into DSP solutions.

I'll also add -- imagine some dude on YouTube with no knowledge of astrophysics discussing how the planets are formed. He would sound like an idiot compared to Neil Degrasse Tyson. In other words, listen to people who have been designing speakers for decades, not some inexperienced YouTuber. A basic knowledge of speaker design will help you identify those who know what they're talking about from those who shouldn't be doing videos on the subject.   

[DannyBadorine]

As most of us know an x-over contains caps and inductors.
There is some agreement that caps and inductors should be avoided if possible due to the phase shift these tend to introduce.
Avoiding caps and inductors in a passive x-over is however not possible so why not just discard the x-over altogether?

There isn't much agreement that crossovers should be avoided.  There is a small faction of people who build speakers without them because they are concerned with what it does to the phase shift.  But if you use measurements properly you can get the phase shift and frequency response in a good place with crossovers.  Plus, with the limited bandwidth of drivers you need to use the crossovers to limit which frequencies they play.  This helps reduce distortion, over excursion and off-axis issues that are often more problematic than phase shift in a crossover.  Which brings me to my problem with the video.  He's just talking about what he hears so it's just his opinion.  The measurements will tell us a lot more about how most people and rooms will respond to the speakers, but he isn't taking any so I see no value in the video.
That being said, I enjoy the idea of designing a speaker and getting the driver placement, driver selection, baffle size/shape, etc. correct before or without a crossover.  So go for it and post some results!  There are many approaches to this hobby!

[FullRangeMan]

Well, I am sure there are people who always will praise XOs as a magical device implying its capable of creating excellent sound from the aether, putting them as an end in itself or worth to be upgraded, pretending they are important as the drivers themselves.

The necessity of using XOs is a patch to allow the use of two or more drivers with no identical Voice Coils to they be aligned in freq, but if all the drivers use the same VC (usually FR drivers) there is no reason to use a XO, unless the guy is a engineer or work for a speaker manufacturing company, which constantly is the case. Worth remember simple two drivers 2-way XO has 2 freq cuts not one, and a three drivers speaker 3-ways XO has four freq cuts per loudspeaker not three cuts.

XOs damage the music signal in many ways not only phase linearity:
1) Phase linearity are lost in the inductors freq cuts.
2) Musical notes harmonics are lost as heat in the XO parts.
3) Smear the music small details.
4) Remove the 3D ambience that are lost as heat in the XO parts.
5) Lost the original time frame alignment of the musical notes ploted during the recording of the music,
6) Decrease the speakers overall sensitivity.

A genius engineer may have success in fixes the phase shift in a first order XO, but its very time demanding.  But items 2 to 6 are losses in the micro Volt range in the XO parts as heat and there is no way to recover this low energy. To make things worse the instruments individual image and the 3D soundstage ambience is formed by the time alignment of the musical notes and harmonics during the recording of the music, unfortunately once this time set has been lost in the XO as heat there is no way to recover the original time set configuration, as expected the final result was a 2D soundstage in all speakers I have listened in all these years.

So far these are facts from electrical theory, henceforth is my personal opinion as follow:
It is clear that XOs are a expensive musical poison and should or could be used only when necessary with no expectations of fidelity to the original musical recording signal, but what we see in the audio industry is the free and widespread use of XOs as a general rule and even as a mandatory standard to ''good sound'' similar to the Tubes x Transistors dilemma, in both cases the reason for this technological deviation is the same.

Several times I saw some specimen engineers proudly using Notch Filters even with an sole peaky FR driver loudspeaker due their lack of knowledge on how treat the boxed enclosure internally to attenuate the hi freqs, so as expected the final result is not good.

Today my favorite approach to speakers is the F18 OB in a 15M² room direct from the amp, none resistor or cap in the way, its cheap and faithful to the recording, this is a Hi-End purist project, no DSP, no xover, no woofer need to my taste, no Tweeter, no Phase rotation, no driver sensitivity loss, no Harmonics loss, no Retail price, but its not fancy, no elegant or imposing as a glossy piano black cabinet in a dealer demo room.

[emtor]

I'll also add -- imagine some dude on YouTube with no knowledge of astrophysics discussing how the planets are formed. He would sound like an idiot compared to Neil Degrasse Tyson. In other words, listen to people who have been designing speakers for decades, not some inexperienced YouTuber. A basic knowledge of speaker design will help you identify those who know what they're talking about from those who shouldn't be doing videos on the subject.   

Perhaps Gilbert Briggs was one of those dudes who didn't know what he was talking about when he designed the Wharfedale SFB/3 open baffle speaker back in the 1950's?
He used a 12 inch woofer and a 10 inch midrange in parallel - no x-over for those two drivers and a tweeter with a cap in series.

[T4Man]

It's been awhile but using a piezoelectric tweeter with a full range driver has been a common solution.

[Early B.]

The necessity of using XOs is a patch to allow the use of two or more drivers with no identical Voice Coils to they be aligned in freq, but if all the drivers use the same VC (usually FR drivers) there is no reason to use a XO, unless the guy is a engineer or work for a speaker manufacturing company, which constantly is the case.

I wish it was as simple as plopping a driver or two in a box and VIOLA! -- exceptional sound emerges. A crossoverless speaker is often used as a marketing ploy. Even a speaker consisting of only a full-range driver can benefit from a crossover. That's because almost no drivers on the market have a perfect frequency response, especially full-range drivers. Part of the benefit of the crossover is to correct inherent issues in the drivers. Unless the full-range driver you're using is perfectly designed, you'll hear every flaw it has. It would be analogous to eating a meal without seasoning; crossovers make music more palatable.   

[emtor]

I wish it was as simple as plopping a driver or two in a box and VIOLA! -- exceptional sound emerges. A crossoverless speaker is often used as a marketing ploy. Even a speaker consisting of only a full-range driver can benefit from a crossover. That's because almost no drivers on the market have a perfect frequency response, especially full-range drivers. Part of the benefit of the crossover is to correct inherent issues in the drivers. Unless the full-range driver you're using is perfectly designed, you'll hear every flaw it has. It would be analogous to eating a meal without seasoning; crossovers make music more palatable.

Every road has one ditch on either side to fall into.
In one ditch you'll find the extremes of "less is more", and in the other ditch, "the more the merrier".
Especially in the world of audio reproduction any attempt to cure one problem often creates a new one.
There's a thread somewhere on this forum were a user buildt an OB speaker with the Visatone B200 and were annoyed by an unpleasant peak in the B200 frequency respons which is typical for this driver.
When trying to tame the respons peak by adding a resistor and an inductor he felt that the B200 lost other desirable characteristics.
Well,-such is life . . .

[Early B.]

Every road has one ditch on either side to fall into.
In one ditch you'll find the extremes of "less is more", and in the other ditch, "the more the merrier".
Especially in the world of audio reproduction any attempt to cure one problem often creates a new one.

You're right. I suppose it also depends on what level of sound quality one is seeking. If you want "good" sound, the options are endless -- a Bose soundbar will work for most people. However, if you want to buy or build exceptional "audiophile quality" speakers, there's a 99.78% chance it's gonna have an active or passive crossover. Even Lii Audio's OB speaker contains a crossover: https://www.lii-audio.com/product/pair-liionidas-extreme-open-baffle-and-crossover-and-drivers-high-class-ob-solution/

[opnly bafld]

As most of us know an x-over contains caps and inductors.
There is some agreement that caps and inductors should be avoided if possible due to the phase shift these tend to introduce.
Avoiding caps and inductors in a passive x-over is however not possible so why not just discard the x-over altogether?
The Hifi Cave channel on YouTube does exactly this by connecting a 15 inch driver and an 8 inch driver in parallel.

https://www.youtube.com/watch?v=85VLiXg0eYc

So, what do you all think of this?
Good or bad?

Bad, but if you try it and think it is better.......

[FullRangeMan]

Even Lii Audio's OB speaker contains a crossover: https://www.lii-audio.com/product/pair-liionidas-extreme-open-baffle-and-crossover-and-drivers-high-class-ob-solution/

This is a shame, just a reason to charge a hi price ticket for this assembled model. They have a 12'' FR brother from this 12'' woofer, but was used the different 10'' FR to profit more.

Crossoverless FR drivers are the max fidelity possible but they are not profitable to the manufacturers, the price is too low, F-15 for just $399 pair.

[JohnR]

Or, it could be that they do it that way because it works better.

[Zuman]

Every road has one ditch on either side to fall into.

Taking a momentary sidetrack...
I'd never heard that aphorism before, yet I instantly understood what it meant! I Googled it and didn't find anything similar; did you invent the phrase, Emtor?
Seriously, while multidriver x-overless speaker systems are important, inventing a really good new maxim is really exciting!
The nearest I found to it is an Irish proverb "For every mile of road there are two miles of ditches," which supposedly means that there are two sides to every story, apparently coming from areas where 'ditches' means 'hedges.' That's not quite the same as Emtor's usage, where he's warning that going to an extreme on either side of a position tends to result in disaster (or lack of progress).
Cool stuff!