Thoughts on Speaker Selection

[Grizaudio]

Hi there, 

 

I'm looking at taking a deep dive into a large high efficiency  3 way tower.

I posted some time back, and drifted away from my DIY build, but I'm back and willing to give it another try. 

I'm hoping to leverage a few of the speaker building brains around here, to help guide the initial design decisions prior to speaker drivers being purchased. 

 

My key goals are: 

- To learn more about high efficiency speaker design, and directivity matching, ideal driver pairing etc  

- Keep things as simple as possible

- Produce a speaker that provides an experience and sound which is superior to a similarly priced commercial speaker

- Ability to make something cheaper the say a Troels 'The Loudspeaker' which selects quite expensive drivers 

- To go active meaning crossovers, PEQ, and experimentation will be far easier (Potentially Dayton DSP 408, running Pioneer N70a source, RME ADI 2 dac for volume control), likely Hypex amps NC400 or similar.    

 

Speaker Goals: 

- Full range, dynamic sound, natural sound, detailed but not harsh, no harshness through 5-8khz for female focal. 

- Strong Bass to 35-40hz, I listen to alot of electronics bass, punchy rock, folk, etc everything really. 

- Design will be active so sealed bass enclosure with EQ possible to reduce enclosure size

- Used for Hifi Listening 

 

Aesthetically something approximately like; Horn, 10, 15inch. 

 

 

My current room size (Not forever): 

- Converted bedroom circa 3.5x 3.2m

- Speaker to ear distance roughly 2.5m 

- Acoustic Absorption front and rear walls.

- Side walls 1x Window, 1x Sliding cupboard 

 

Driver ideas: 

HF

FAITAL HF109 or equivalent 

HF109 by FaitalPRO

FAITALPRO.COM

---

FaitalPRO combined the latest R&D methods and technologies with the most advanced industrial automation techniques and all FaitalPRO drivers are made in Italy with the highest level of...

OR: DE250

B&C Speakers

WWW.BCSPEAKERS.COM

 

 

Horn

 

E-JMLC-600 – Horns by Auto-Tech

HORNS-DIY.PL

OR

SEOS, B&C ME20, etc equivalent 

 

Mid

 

I like the response of this driver 

10inch 10CL51

B&C Speakers

WWW.BCSPEAKERS.COM

 

Or 8inch 8PS21

B&C Speakers

WWW.BCSPEAKERS.COM

 

 

Low Bass

AE TD15S, TD15H (Vented or selaed) or something like this which is cheaper: 

Eminence Kappalite 3015LF-4 High Power Neo 15" Subwoofer 4 Ohm

WWW.PARTS-EXPRESS.COM

---

Eminence Kappalite 3015LF-4 High Power Neo 15" Subwoofer 4 Ohm

 

 

[davewantsmoore]

Hi Steve.

 

10 hours ago, musicbee said:

directivity matching

This is the most important part.

 

Inexperienced loudspeaker designers often focus on optimising the response of their speaker from one specific angle of radiation (or "measurement location) ..... and don't pay enough attention to the speaker response at other angles.

 

We do hear that initial sound (the sound reaching your ears directly from the speaker) as the dominant sound, and so it is important .... BUT, the loudness and frequency response of the later arriving sound (reflected from the room) affects this dramatically.     It's why listening to the same speaker in the bathroom, garage, living room, or outdoors, all sound wildly difference.

 

The goal in designing the speaker is to make the later arriving sound have the same frequency response shape (but not necessarily the same level, it could be lower in level) as the first arriving sound.

 

The things which conspire to affect this are:

• Shape of the cabinet
• Size/shape of the speakers
• Location of the speakers relative to cabinet, other speakers, and room surfaces

 

So... the most important thing... for example.... if you were going to use X horn ...... would be what size cone to pair with it .... and where to locate this cone ..... Not so much whether the response of the cone looks good, or if the cone is "high performance"....  as long as the performance is "high enough", and the response of the cone can be corrected to what you need it to be using the crossover filters.

 

Inexperienced loudspeaker designers often spend a lot of time focussing on "which 10" driver" .... rather than, "should I be using an 8 or 10 or a 15" driver" ... and, where should I locate it on the cabinet.

 

Quote

Aesthetically something approximately like; Horn + 10

Centre of ear height
Driver locations, etc.

These things are the degrees of freedom which go into a loudspeaker design....  setting them at the outset makes the design process more restrictive and often more difficult.

 

... but of course, the flip size is not setting them, means you need to build prototype cabinets.

 

Copying an existing cabinet design, driver size combination and driver layout.... is a good place to start.   Then you just figure out your own crossovers and target response.

 

Quote

JMLC, SEOS, B&C ME20, etc equivalent 

These are all very different horns.

 

For example.  If you compare the directivity sonograms (the coloured plots) for the horn in "the loudspeaker" with the JMLC600

 

http://www.troelsgravesen.dk/18TH/XT1086.PDF

http://horns-diy.pl/wp-content/uploads/2015/07/E-JMLC-6001.pdf

 

They're quite different... and will sound quite different, even when both setup (with your crossover filters, and EQ) to have the same response on the listening axis.

 

Quote

Ability to make something cheaper the say a Troels 'The Loudspeaker' which selects quite expensive drivers

You could (for example) copy this design, using the same horn, and much cheaper drivers (but the same size, and same location).

 

The loudspeaker performance is more about the size/location of the drivers, and the crossover filters which blend them .... than it is about the "quality" of the drivers used (within reason).... If I was asked to comment on a hypothetical speaker where one used $50 drivers, and the other $500 drivers .... I would ignore the drivers, and say, show me the crossover and the acoustic design  (ie. what is the frequency response vs angle?).

[davewantsmoore]

Quote

Speaker Goals

Have you considered going for a 2-way + subwoofer(s).

 

If you go for a horn+midbass, you can make the main speaker cabinet size quite a bit more modest ... and then position the subwoofer where you like.

[henry218]

Hello,

 

i got your PM. I tried to help as much as i can.

 

my suggestions are

1. The planned speakers will be too large for the room.

2. Keep it simple as 2way passive (xo with horn wont be simple) + active dsp subs (more than 1)

3. Use preamp with dual outputs so you can use line level with the subs.

 

selection of waveguide are plenty for compression driver (faitalpro, eighteensound etc) or diysoundgroup.

 

[Grizaudio]

Thanks Gentlemen much appreciated. 

I was considering a 2way, Like a AE TD10/12M and horn, or 4PI. 

 

I was hoping to stay away from using subs.

But I am open to whatever will work better. 

I'll digest this info. 

 

Are there any quality 2way designs you would recommend?

- 4PI 

- Econowave

 

Many thanks 

Edited December 3, 2019 by musicbee

[Grizaudio]

4 hours ago, henry218 said:

Hello,

 

i got your PM. I tried to help as much as i can.

 

my suggestions are

1. The planned speakers will be too large for the room.

2. Keep it simple as 2way passive (xo with horn wont be simple) + active dsp subs (more than 1)

3. Use preamp with dual outputs so you can use line level with the subs.

 

selection of waveguide are plenty for compression driver (faitalpro, eighteensound etc) or diysoundgroup.

 

Thanks Henry, 

 

I currently run 12inch 3 ways which work well with the space.  

I'll look into 2 way designs as suggested. 

Cheers 

 

[henry218]

47 minutes ago, musicbee said:

Thanks Henry, 

 

I currently run 12inch 3 ways which work well with the space.  

I'll look into 2 way designs as suggested. 

Cheers 

 

What kind of improvement that you’re looking for over the current speakers?

[A9X]

First up, they're definitely not too large for the room. I ran a similar system for years in a room as wide, but longer, even though I sat at about the same distance.

 

I built my first system like you have proposed at least 15 years ago. It was JBL 2226/2123 and an old set of Yamaha radial horns (about the same size as Altec 811s) with a Beyma CP380/M. Active of course. I've made other variants of this in the interim, the last being similar in format but with AE TD15X, TD10M, QSC clone flares (I'll look up the part number on PE later if interested) with DE250s. These were my surrounds, but the MF/HF is going to be Faital 8HX200 coaxes in the new incarnation.

 

Gotta get ready for work, but I'll answer any questions you have later.

[Grizaudio]

On 03/12/2019 at 6:06 PM, henry218 said:

What kind of improvement that you’re looking for over the current speakers?

I'm pretty happy with my speakers. 

They run a dome mid and dome tweeter. 

 

The main reason for the DIY is: 

- Having a CD horn speaker at a reasonable cost. I like JBLs. 

- I have always liked high efficiency speakers

- To build something and tinker - Have fun

 

[Grizaudio]

On 04/12/2019 at 5:20 AM, A9X said:

First up, they're definitely not too large for the room. I ran a similar system for years in a room as wide, but longer, even though I sat at about the same distance.

 

I built my first system like you have proposed at least 15 years ago. It was JBL 2226/2123 and an old set of Yamaha radial horns (about the same size as Altec 811s) with a Beyma CP380/M. Active of course. I've made other variants of this in the interim, the last being similar in format but with AE TD15X, TD10M, QSC clone flares (I'll look up the part number on PE later if interested) with DE250s. These were my surrounds, but the MF/HF is going to be Faital 8HX200 coaxes in the new incarnation.

 

Gotta get ready for work, but I'll answer any questions you have later.

I agree. 

I like large speakers, they are effortless.

DSP can help address many room abnormalities.

I use an RME dac to do this currently. I.e. Tame 50hz gain, etc. 

 

I was really hoping to get some advice about the driver combination, not about whether I am qualified or whether I should go with a DIY speaker.

You need to start somewhere, and experience comes from experience. 

 

I have a good fundamental knowledge of pro audio, DSP, speaker management, gain structure, and venue systems etc. 

I also have decent word working skills. I just don't have a lot of speaker building experience only having built one DIY speaker set previously.   

 

As such I was hoping to get some advice about horn selection with the 8 or 10inch mid, and there combination. 

I'm not stuck on any drivers, I am happy to change drivers as required, or as freq directivity dictates.  

 

The B&C de250 running into the PS21 has been done so many times. It seems pretty low risk to me.  

With an ME20 or SEOS horn/wave guide I don't think much can go wrong.

I was just hoping for some guidance with this combination and crossover selection. 

I believe the crossover would be around 1.5-1.8khz, as the PS21 has some peaks around 2k.  

 

 

 

 

 

 

 

 

[A9X]

10 hours ago, musicbee said:

DSP can help address many room abnormalities.

And driver abnormalities.

 

10 hours ago, musicbee said:

I was really hoping to get some advice about the driver combination, not about whether I am qualified or whether I should go with a DIY speaker.

As you were quoting me in this post, please point to where I questioned your abilities. I said you should go ahead, and it will work.

 

10 hours ago, musicbee said:

As such I was hoping to get some advice about horn selection with the 8 or 10inch mid, and there combination. 

I'm not stuck on any drivers, I am happy to change drivers as required, or as freq directivity dictates.

You will need to choose xover depending upon the directivity of the individual drivers as even those with a nominal driver size the same will vary between models to a small extent.

 

10 hours ago, musicbee said:

With an ME20 or SEOS horn/wave guide I don't think much can go wrong.

The ME20 has a pretty awful throat transition IIRC. Where are you going to get a SEOS? DIYSG never seem to have any, so Poland is the only source, and shipping is $ and the price whilst reasonabl-ish, will make them expensive.

 

The QSC clone I mentioned, doesn't appear to still be listed on PE. Mine are actual QSC I got before they changed the rules.

 

If you are willing to accept a higher xover and a 1 3/8 screw on the the JBL EWave flares are really excellent. Depending upon the driver below, a 1k7/1k8 xover will be fine.

 

The 18Sound XT1086 sound pretty good on the short test I made with them (with DE250s). I haven't a project to use mine in yet.

 

The JBL2370 and clones are old fashioned diffraction slot units and not as good as modern units, in my experience.

11 hours ago, musicbee said:

I was just hoping for some guidance with this combination and crossover selection. 

I will only speak about what I've actually used. If you want me to suggest drivers that pique my curiosity, I'm happy to suggest them, but caveat emptor.

Not many around here have much/any experience in this type of design.

 

On 02/12/2019 at 11:36 PM, musicbee said:

Design will be active so sealed bass enclosure with EQ possible to reduce enclosure size

With DSP, this makes 6th order ported (note; this is not bandpass) possible with the correct driver. Some of my PA enclosures using the JBL2226 were 40Hz tuned in about 40L net.

 

With most drivers in this general format, build the box, add in xovers at 250-300 and 1k7 and set levels and delay, and in less than an hour, you'll have a better sounding speaker than most can buy. Fine tune with measurements and it'll be even better.

[Grizaudio]

Thanks for your response, much appreciated.  

 

Some additional horns I was considering were: 

- Dayton H6512

- Dayton 812

- Faital LT102

 

These are obviously much easier to source. 

The horns were tested here subjectively using a 1.6khz crossover.

https://speakerprojects.wordpress.com/2017/08/29/bc-de250-8-compression-driver-in-various-waveguides/

 

Do you have any experience with these horns and driver combination? 

I would also be interested in feedback between the DE250 and the latest Failtal HF109 etc CD's. 

The Faitals appear to have a more linear HF response. 

 

 

 

 

 

 

 

 

 

 

 

 

[henry218]

the questions, suggestions and comments were not to undermined you as speaker builder, i apologise if it came out that way.
 

if dynamics is your main priority, then yes go as big as you can/design allowed.

 

however if the goal is to have the best musical performance from the speakers holistically, then you have to consider the room and speakers proportion. One of the most important factor for me is to have the speakers disappear and just play music in front of me. 

 

As you are going to use DSP, it will be very flexible for you to tailor the response to use any drivers combo.

 

while many drivers can be tuned similarly, ultimately it will have differences on how the transfer function works between the MT (on any drivers combination) and the inherent character of the driver it self (materials, magnets, combination of the soft part of the woofers and CD waveguide relationship)

 

my tip will be :

aim for linear response at on axis and off axis (with the correlated roll off of course)

 

have fun and good luck 

[Sub Sonic]

On 06/12/2019 at 8:22 AM, musicbee said:

Thanks for your response, much appreciated.  

 

Some additional horns I was considering were: 

- Dayton H6512

- Dayton 812

- Faital LT102

 

These are obviously much easier to source. 

The horns were tested here subjectively using a 1.6khz crossover.

https://speakerprojects.wordpress.com/2017/08/29/bc-de250-8-compression-driver-in-various-waveguides/

 

Do you have any experience with these horns and driver combination? 

I would also be interested in feedback between the DE250 and the latest Failtal HF109 etc CD's. 

The Faitals appear to have a more linear HF response. 

 

 

I have played with the Dayton H812 and the SEOS 15. The Dayton is more directional at higher frequencies, ie the SEOS has better (subjectively at least) controlled directivity.

 

SS

[davewantsmoore]

On 03/12/2019 at 5:14 PM, musicbee said:

I was hoping to stay away from using subs

If you are designing a 3 way, then it's much easier to design the XO at 80Hz (ie. subs) than it is at ~400Hz.

 

You can still put the subs inside the mean speaker boxes if you like.   So it's just like a "typical 3 way".

 

On 03/12/2019 at 5:14 PM, musicbee said:

But I am open to whatever will work better.

Anything can work well, if designed well.

 

Designing a 3-way speaker with a XO at ~400 (for example) is not trivial.

 

On 03/12/2019 at 5:14 PM, musicbee said:

- 4PI 

- Econowave

Yes, either.