Full Range Drivers

[MrBoat]

I too would be interested in TLS' design. I've been eyeing the Solstice, but this would be less expensive and quite a bit more sensitive.

I am curious as well. Especially after that link to that brochure he posted. It would be interesting to see where he is coming from with this.

 

[TLS Guy]

Before I involve you too much and make you waste your time, what is the rough physical size of what we are talking about here. This will tell me more than anything if, or how, I can fit them in what space I have in this room. As it stands now, my other efforts allow me to not have to move my main speakers out of the room. Stands and such I can weasel in and about. Without moving anything, I have two, 16" wide slots on either side of my television at about 55" on center with about 36" of room between the back wall and the ends of the sofas. This is about 7-9 ft away from my main listening position.

The other alternative is to vacate an addition (12'x20') room of everyone else's stuff, and make another listening room, which is a possibility.

A TL has a lot of flexibility of design. You have a tapering pipe and at least one fold. The fold does not have to be at the half way point, so this means the height can be higher than half the pipe length and the turn. The pipe length is 65" and so half would be 37.5 inches and then the turn.

So we are talking about a minimum height of about 43 inches likely. This would place the tweeter in an MTM configuration at ear height. The total pipe volume is 1.31 cu.ft, not allowing for the volume of the internals.

Th outside diameter of the drivers is about 6.5 inches. The cabinet would be as narrow as possible to fit the drivers.

With a 4 to 1 linear taper the internal depth will be around 10". It won't really matter if the pipe opening is at the bottom or the top. The total depth will end up around 1 ft I suspect.

Can you make that work in your space?

Really all I need to know is how high the enclosure needs to be for the bottom of the lower driver to be clear of your furniture. Then I can determine how to lay out the pipe.

Here is the lay out of one of my lines. This line has a couple of turns. There needs to be at least one, as otherwise there is too much HF radiation from the port.

This is the full specification of the pipe for your design.

Total pipe length - m 1.65 Stub length - m 0.00 Throat area - sq cm 360.00 Exit area - sq cm 90.00 Taper - linear Total volume - liters 37.13 Stuffing - Acousta Stuf Grams per liter 8.00 Damping lowpass - Hz 10.00 Slope - dBi / octave / m 0.50 Losses - dBi / m 6.08 Velocity coefficient 0.97 Radiation - hemispheres 1.00

 

[TLS Guy]

Greetings Mark,

Have you ever heard of the Phi Full-Range speakers? I had the opportunity to hear a pair at one of the Audio shows several years ago in Montreal. I found them very smooth but they weren't cheap.

You can have a look: http://www.phi-audio.com/

Cheers,
André

I have not come across those.

 

[Verdinut]

I have not come across those.

Searching further as I read that the site I referred to seemed to be inactive since 2014. Also, that was not the right company.

I found the new site which shows the complete line of the PHY drivers available at present:

http://www.phy-hp.com/

 

[Verdinut]

Been eyeing these boxes or just to see what these full range designs encompass or something I might would understand compared to what I have been exposed to. Seems there is a lot more to it than I expected. Evident by the work some of these companies are putting into these drivers.

Mr Boat,

I finally found the right loudspeaker company I was referring to:

http://www.phy-hp.com/

 

[MrBoat]

A TL has a lot of flexibility of design. You have a tapering pipe and at least one fold. The fold does not have to be at the half way point, so this means the height can be higher than half the pipe length and the turn. The pipe length is 65" and so half would be 37.5 inches and then the turn.

So we are talking about a minimum height of about 43 inches likely. This would place the tweeter in an MTM configuration at ear height. The total pipe volume is 1.31 cu.ft, not allowing for the volume of the internals.

Th outside diameter of the drivers is about 6.5 inches. The cabinet would be as narrow as possible to fit the drivers.

With a 4 to 1 linear taper the internal depth will be around 10". It won't really matter if the pipe opening is at the bottom or the top. The total depth will end up around 1 ft I suspect.

Can you make that work in your space?

Really all I need to know is how high the enclosure needs to be for the bottom of the lower driver to be clear of your furniture. Then I can determine how to lay out the pipe.

Here is the lay out of one of my lines. This line has a couple of turns. There needs to be at least one, as otherwise there is too much HF radiation from the port.

This is the full specification of the pipe for your design.

Total pipe length - m 1.65 Stub length - m 0.00 Throat area - sq cm 360.00 Exit area - sq cm 90.00 Taper - linear Total volume - liters 37.13 Stuffing - Acousta Stuf Grams per liter 8.00 Damping lowpass - Hz 10.00 Slope - dBi / octave / m 0.50 Losses - dBi / m 6.08 Velocity coefficient 0.97 Radiation - hemispheres 1.00

I was looking at those Alpair-10s. This would be doable with narrower cabinets as you note with now about 6 ft of separation possible and perhaps even more if I shrink my end tables, which I was planning to do anyway to a round top style because I toe-in my current speakers and round tables would give me more adjustment options. I am definitely interested in trying this. It will take me a little longer to save for the additional drivers etc for an MTM design.

25" gives me about an inch of clearance over the ends of the sofas with my seated ear height being about 43" if that matters. I can solder well and follow schematics. There is 3 ft of space between the back wall and the sofas and this would put the speakers about 2 ft-30" away from the side walls. When I am using my other speakers, I could slide these back and closer to the TV.

 

[TLS Guy]

I was looking at those Alpair-10s. This would be doable with narrower cabinets as you note with now about 6 ft of separation possible and perhaps even more if I shrink my end tables, which I was planning to do anyway to a round top style because I toe-in my current speakers and round tables would give me more adjustment options. I am definitely interested in trying this. It will take me a little longer to save for the additional drivers etc for an MTM design.

25" gives me about an inch of clearance over the ends of the sofas with my seated ear height being about 43" if that matters. I can solder well and follow schematics. There is 3 ft of space between the back wall and the sofas and this would put the speakers about 2 ft-30" away from the side walls. When I am using my other speakers, I could slide these back and closer to the TV.

OK, that gives me time to design the line to those specs.

My wife had a total knee replacement 10 days ago, so I'm Head Cook and Bottle Washer" right now.

 

[Swerd]

My wife had a total knee replacement 10 days ago, so I'm Head Cook and Bottle Washer" right now.

Take good care of her. I hope she has a full and rapid recovery.

 

[MrBoat]

OK, that gives me time to design the line to those specs.

My wife had a total knee replacement 10 days ago, so I'm Head Cook and Bottle Washer" right now.

By all means tend to your wife first! Hope she gets well soon.

I'm in no hurry. I still have Jeff Bagby's Continuum kit arriving Monday. Then it's going to be a little bit before I can realistically justify anymore speaker parts so this portion of my interest does have a little time to evolve.

Meanwhile, I am reading and trying to understand the benefits of TL or MLTL enclosures being it is such a departure from what I have used and what I am currently using.

But while we're on the subject, and being you favor this approach, why MTM with full range when you see so many MLTL or BR enclosures using a single driver? Will the arrangement you have be more stable at higher listening levels? What about BSC? Being they use very little if any networking with these designs, how is that handled? Is it built into the drivers somehow?

 

[MrBoat]

I did order 2 of these drivers to play with. In the event I end up working on TLS's design, I won't have to buy all the parts at once. That would only leave two more of these FR drivers, tweeters and whatever crossover parts needed.

Markaudio Alpair - 10m

A good start at any rate.

Been doing a lot of reading on this subject. I could put these in a reasonably simple BR enclosure just to try them out by themselves.

A couple things that somewhat confuse me is, the notion that these types of speakers supposedly work better with tube amps. I don't know if that is some purity thing, along the same lines as vinyl being the only legitimate path to hifi for some. I really don't want to get into tube amps. The trendites have priced that out of practical range for a working stiff like me.

 

[Swerd]

A couple things that somewhat confuse me is, the notion that these types of speakers supposedly work better with tube amps. I don't know if that is some purity thing, along the same lines as vinyl being the only legitimate path to hifi for some. I really don't want to get into tube amps. The trendites have priced that out of practical range for a working stiff like me.

Some stuff you gotta just shake your head and ignore it.

 

[MrBoat]

Some stuff you gotta just shake your head and ignore it.

In my mind, these types of speakers seemed more ripe for the lower powered, class D amplifier boards for simplicity sake, or perhaps one of the Gain Clone amps.

 

[MrBoat]

After reading, and reading s'more on full range drivers, I keep getting the feeling that perhaps instead of full range goals, these drivers could more easily be treated as 'extended' range drivers instead of full. The reason I say this, based on next to no experience at all is, With two-way, or 3-way speakers, the drivers are tasked in a way to relieve it's counterpart in that they perform at what they do best.

The current school of thought has us crossing our main speakers over to our subwoofers at say, around 80hz, even though the main speaker may well reach quite lower effectively on it's own. The more I read about full range speakers and the enclosures designed for them, one of the primary (seemingly most challenging) goals is adequate bass.

One of the first considerations that made me think I might enjoy full range drivers has been desktop computer speakers, many of which use only a pair of small, full range drivers, with the best sounding of these systems employing a subwoofer. In spite of having a decently high performance main system, I still enjoy my desktop system. Granted, it's a near field setup, but that is not a handicap to me. That used to be a style of listening even with more capable systems and I still often situate myself that way with my larger system.

Somehow, they manage to eek out a pretty reasonable sound quality in the mid-upper ranges even with some comparatively budget offerings compared to multi-way speakers. It was one of my first surprises with sound quality in small packages after taking a hiatus from audio for a number of years. It shouldn't be true, following the popular logic around multi-way systems so, there has to be something to this full range driver idea. Even more so, knowing what we do about subwoofers these days.

 

[shadyJ]

If it were me, I would use a tweeter and a sub with a driver like that. As you say, I would use it as a wide-band driver, not a full-range driver. Look at the frequency response, I am betting that elevation at 8 kHz to 10 kHz is breakup. I would think about low-passing it around 3 to 4 kHz and use a tweeter in that range. It is not going to be the bass king either, so use a sub to keep it away from high excursions.

If used on a desktop system, think about a way of elevating the speaker off the desktop surface to reduce acoustic reflections off the desktop. The reflections off of desktops can be quite severe, and cause real peaks in upper bass frequencies. Think about using measurement and equalization for a desktop system to reduce those peaks, so you might as well consider an active crossover system.

 

[MrBoat]

If it were me, I would use a tweeter and a sub with a driver like that. As you say, I would use it as a wide-band driver, not a full-range driver. Look at the frequency response, I am betting that elevation at 8 kHz to 10 kHz is breakup. I would think about low-passing it around 3 to 4 kHz and use a tweeter in that range. It is not going to be the bass king either, so use a sub to keep it away from high excursions.

If used on a desktop system, think about a way of elevating the speaker off the desktop surface to reduce acoustic reflections off the desktop. The reflections off of desktops can be quite severe, and cause real peaks in upper bass frequencies. Think about using measurement and equalization for a desktop system to reduce those peaks, so you might as well consider an active crossover system.

That's probably what TLS was addressing using these drivers with a tweeter and a crossover mentioned earlier in this thread. On the Markaudio site, they have a simple bass reflex enclosure listed for this driver stand alone, otherwise. Of course there are other enclosures there and elsewhere. I would not mind using it with a tweeter regardless.

 

[TLS Guy]

That's probably what TLS was addressing using these drivers with a tweeter and a crossover mentioned earlier in this thread. On the Markaudio site, they have a simple bass reflex enclosure listed for this driver stand alone, otherwise. Of course there are other enclosures there and elsewhere. I would not mind using it with a tweeter regardless.

I will try and PM you the files tomorrow, if I get a chance. I have a couple of boats to get in the water tomorrow.

 

[MrBoat]

I will try and PM you the files tomorrow, if I get a chance. I have a couple of boats to get in the water tomorrow.

No worries or hurries. I know you have your hands full. I am 'collecting' parts so I have time. Just reading around trying to familiarize with the 'whys' of certain designs. Parts in hand are one of the greatest motivators.

Either way, I sincerely appreciate your interest in this project. It's these little side trips that I end up learning the most from. Hands-on, even more so.

 

[Verdinut]

I agree with Shady on the suggestion of using that kind of driver as mid-range speaker in a three-way system, with a subwoofer used as a woofer. I would also suggest an Air Motion Ribbon tweeter such as the Airborne RT-4001 which has a very smooth frequency response and a wide horizontal dispersion: https://solen.ca/wp-content/uploads/rt4001.pdf

Of course, the possibility would exist if their relative efficiency is close. That could be an excellent match. Both Solen and Meniscus carry the Airborne line.

The advantage in a 3-way system, is that you can divide the frequencies outside the critical range of 300 to 3000 Hz. For instance, my three front cabinets contain 3-way systems which consist of the above mentioned tweeter, two Peerless P830991 5¼" Mid-woofers and a Dayton RSS390HF-4 sub. The filter frequencies are 190 Hz and 3500 Hz. Those speakers are amazing and I just have to eventually EQ them mainly for the low frequencies because of room interaction.

If the Markaudio full-range driver has a relatively smooth response between 300Hz and 4KHz, a close sensitivity to that of the RT-4001, then you would be all set to proceed with a very decent 3-way system. The Airborne tweeter has an efficiency of around 94dB. If possible with the response of this Alpair speaker, I would crossover at between 3200 and 3500 Hz to the tweeter, and at around 250-275 Hz Hz to a good sub, one Dayton RSS210HF-4 for instance. This is an 8" subwoofer. If you decide on this sub, I could figure out for you a decent BR cabinet size for it. Both the tweeter and the mid-range driver could be installed in a closed box within the subwoofer cabinet.

As for the series inductor for the sub, I have used the Jantzen P-Core Coils which have a very low resistance and are rated at 400 watts before saturation. They work pretty well and a lot better than the iron core inductors. Moreover, they are quite cheaper and lighter than an equivalent air core inductance and good enough for a subwoofer filter.

IMO, the 3-way system is the best compromise for a good loudspeaker system. Each transducer operates in its best frequency range, with less possibility of dispersion problems, less cone breakup possibility, less intermodulation distortion and higher power handling as well.

That is what I consider a valid suggestion.

 

[MrBoat]

I agree with Shady on the suggestion of using that kind of driver as mid-range speaker in a three-way system, with a subwoofer used as a woofer. I would also suggest an Air Motion Ribbon tweeter such as the Airborne RT-4001 which a very smooth frequency response: https://solen.ca/wp-content/uploads/rt4001.pdf

Of course, the possibility would exist if their relative efficiency is close. That could be an excellent match.

The advantage in a 3-way system, is that you can divide the frequencies outside of the critical range of 300 to 3000 Hz. For instance, my three front cabinets contain 3-way systems which consist of the above mentioned tweeter, two Peerless P830991 5¼" Mid-woofers and a Dayton RSS390HF-4 sub. The filter frequencies are 190 Hz and 3500 Hz. Those speakers are amazing and I just have to eventually EQ them mainly for the low frequencies because of room interaction.

If the Markaudio full-range driver has a relatively smooth response between 300Hz and 4KHz, a close sensitivity to that of the RT-4001, then you would be all set to proceed with a very decent 3-way system. The Airborne tweeter has an efficiency of around 94dB. If possible with the response of this Alpair speaker, I would crossover at between 3200 and 3500 Hz to the tweeter, and at around 250-275 Hz Hz to a good sub, one Dayton RSS210HF-4 for instance. This is an 8" subwoofer. If you decide on this sub, I could figure out for you a decent BR cabinet size for it. Both the tweeter and the mid-range driver could be installed in a closed box within the subwoofer cabinet.

IMO, the 3-way system is the best compromise for a good loudspeaker system. Each transducer operates in its best frequency range, with less possibility of dispersion problems, less cone breakup possibility, less intermodulation distortion and higher power handling as well.

That is what I consider a valid suggestion.

But I already have great (exceptional even) 2-way and 3 way speakers that would be quite difficult to best at my economic class. I can always try different approaches after the fact. I am also curious to see what it is about full range drivers that use no filters and different enclosure functions.

I have a set of Harman Kardon PC speakers that employ 4-1" drivers in each speaker that probably use about 15 watts and then there is a subwoofer. How in the heck do they get that much clear midrange out of those tiny speakers? These little things fill this room with nice sound and it just seems ridiculous. I reckon these are more of a small line array but still. . . . it doesn't seem natural.

 

[MrBoat]

I should note that my responses are not the least bit dismissive to any suggestions here, regardless of how it comes across in plain text. I appreciate all the suggestions and there is a good chance that I try a bunch of different things over time and I do find all the input helpful to that end.