My Swansong speaker build

[Toppsy]

Thank you Colin for a great day of idle banter, great tunes and a lovely lunch plus many cups of tea - would love to have another session once you have dialled in the frequency response for the final 5% that appears to be astray though I know I wouldn't be able to notice it.

Cheers

T'was great to meet up again and so glad you are still enjoying your 'Jenna' speakers. We'll have to organise something for the new year. By that time we (hopefully) will have fine tuned the bass performance minor niggles. I should reiterate this is a minor niggle with my room acoustics affecting the bass performance. Hopefully after some new in-room measurements, some room treatment and minor tweaks to the DSP settings will have it sorted.

Spoke to Scott last night and I mentioned your minor niggles with the 'Jenna' speakers in your room setting. He confirms we should be able to improve on their performance, what with the extra knowledge we have accumulated since the @Jenna's' were designed. So email me those photos and describe what issues would like addressing and Scott can have a renewed look at the XO and tweeter used to make improvements.

[Nick]

Out of interest, I totted up the cost of the drivers + plate amp. Didn't include the xover parts as I don't know what they were. Got to almost exactly £3k. Not cheap by any measure but about the same price as a single AER BD2 for comparison.

[Scottmoose]

Definitely good value in outright terms. Be interesting to remeasure the room acoustics with the additional damping panels & see how this affects the behaviour in the mid-upper bass region.

Yes, no reason why we can't improve on the original Jenna design; a decade or so of additional experience under the belt helps somewhat.

[Toppsy]

Out of interest, I totted up the cost of the drivers + plate amp. Didn't include the xover parts as I don't know what they were. Got to almost exactly £3k. Not cheap by any measure but about the same price as a single AER BD2 for comparison.

Just gone through my invoices for all the drivers, the final build + development XO components, and a pair of Hypex amps came to just under £3200 thanks to the discounts I managed to negotiate from the various suppliers. By comparison to what I have to the cost of a single AER BD2 driver I agree that it puts the cost of these speakers into perspective as a venerable bargain.

[gninnam]

Thank you Colin for a great day of idle banter, great tunes and a lovely lunch plus many cups of tea - would love to have another session once you have dialled in the frequency response for the final 5% that appears to be astray though I know I wouldn't be able to notice it.

Cheers

T'was great to meet up again and so glad you are still enjoying your 'Jenna' speakers. We'll have to organise something for the new year. By that time we (hopefully) will have fine tuned the bass performance minor niggles. I should reiterate this is a minor niggle with my room acoustics affecting the bass performance. Hopefully after some new in-room measurements, some room treatment and minor tweaks to the DSP settings will have it sorted.

Spoke to Scott last night and I mentioned your minor niggles with the 'Jenna' speakers in your room setting. He confirms we should be able to improve on their performance, what with the extra knowledge we have accumulated since the @Jenna's' were designed. So email me those photos and describe what issues would like addressing and Scott can have a renewed look at the XO and tweeter used to make improvements.

I have sent the pics etc in a PM
Will definitely be round to have another session once the final tweaks are completed

[chris661]

Had another day at Colin's last weekend, and we set about tweaking these speakers further, to see what could be done about the notch in the response at 100Hz.

After trying a few measurement positioned, we realised that the problem was in the vertical plane: moving the mic a few feet upwards filled in most of the notch. Chances are it was a reflection from the ceiling which was causing a cancellation. The path lengths look about right, but I didn't measure it to be sure.

Fixing that problem acoustically is non-trivial. The only option, really, would be to lose a substantial amount of ceiling height by adding some absorption up there.

Fortunately, there's another way. With 14x midrange drivers, there's a lot of cone area available, and we've seen in other builds that the MA drivers have plenty of mechanical headroom.

We changed the highpass filter from a 2nd order highpass with an impedance-flattening resistor to a single capacitor. When used with a sealed box, a series cap can actually boost the LF output just below Fc. We leveraged that to push the midrange units down to a -3dB point somewhere around 120Hz, which meant they were still helping out enough at 100Hz to fill in the dip.


We also tweaked the EQ in the DSP to get the <100Hz region smooth and even.

With the new settings, the upper-bass "punch" is back without needing lots of EQ, and the rest of the range remains excellent. These speakers are now some of the best I've heard, and I hope Colin takes every opportunity to enjoy them.


Chris

[gninnam]

Great result with the tweaks.
They were already awesome but should be now at another level

[Toppsy]

Had another day at Colin's last weekend, and we set about tweaking these speakers further, to see what could be done about the notch in the response at 100Hz.

High Chris,
I was hoping either you or Scott would post up a précis of the modifications that were carried out last Saturday. Saves the embarrassment of me reporting the day and getting my facts wrong.

First off I must give my heartfelt thanks to you, Scott, NickG and AndrewL for such a great weekend and that down to your combined expertises what you have managed to do with the fine tweaking of these speakers to get them to the point they are now delivering such wonderful sounds. Without you guys I doubt - in fact I know - the speakers would not be as good as they have turned out. Secondly the day proved to me the true value of measuring the actual in room performance of the speakers and the importance of using proper purpose designed software programs and calibrated hardware to achieve the end goals.

With the new settings, the upper-bass "punch" is back without needing lots of EQ, and the rest of the range remains excellent. These speakers are now some of the best I've heard, and I hope Colin takes every opportunity to enjoy them.

Be assured Chris I shall take every opportunity to enjoy these speakers and hope I have many years left of good health and hearing to continue to enjoy them.

On the question of Owston and the possibility of the speakers being taken to the next meet up. I can't see this happening primarily for the following reasons.
1. These are too big to fit into my car and I can't justify the expense of hiring a Transit type van just for this event.
2. They are very heavy and I struggle even with helping hands from a strong young helper to lift them. I am reminded of my spinal surgery and this restricts what lifting I am able, or should/should not, attempt that could undo this remedial surgery.
3. I don't have a suitable sack trolley to help with the lift and can't see the benefit to me in buying one.
4. The possibility of damaging the speakers.

I realise this may be a disappoint (or not) to some but I have no issues with and would welcome anyone wishing to pop over my place for an extended listen, just get in touch and we can arrange something.

[chris661]

A final point on the Owston front, if I may: You're unlikely to hear these speakers at their best there.


When I took the 18" subs to Owston last time, I got the subs + speakers measuring flat with the mic near-ish the cones. Mostly just checking the integration betwee the two.
When I pulled the mic out into the room, the LF response was pretty awful. Lots of peaks and dips, which varied a lot as you move around. I considered, for a moment, trying to figure out some EQ that might help out, but the response curve changed dramatically from seat to seat, such that trying to fix one listening position would likely make another much worse!


Going back to Colin's speakers, the DSP and low/mid crossovers have been tuned to get the best out of those speakers in his room. With the 38Hz notch dialled in properly, the bass is flat to well below 20Hz, and those drivers have enough grunt to make sure you know it. Putting them into any different room would require another round of measurements and optimisation, and a room as big as Owston will be especially problematic.


I wouldn't hesitate to call these speakers world-class, and would highly recommend auditioning them if you can.

Chris

[Ray P]

On the question of Owston and the possibility of the speakers being taken to the next meet up.

Don't even think about it Colin, I would hate to think of anything befalling them or you.

[Scottmoose]

It would definitely be 'unfortunate'.

Colin and I have talked (purely for a yuk or two) about a more generic, purely passive variation on the theme that could be used in different spaces since the lack of a room-specific active EQ curve frees things up* and a shift in the general configuration that couldn't be done with this particular speaker to suit his decor etc. requirements should help a bit with LF modes. However, it would be a 'paper exercise', since he ain't building it (and neither am I ).

*Nothing to stop having a non-specific active low end of course, without any room-specific EQ -this is how Troels's semi-active designs are run. Seems a bit of a waste though.

[iansr]

Sounds like congratulations are in order Colin in relation to your new speakers, I’d love to hear them sometime.

A mildly interesting anecdote (well sort of) about the SBA Be tweeter. A few years ago I exchanged some emails with an American chap called Tom Pezerella (almost certainly incorrect spelling!) who is a very experienced speaker DIYer and who has had several articles published in Audio Express about his speakers. He told me that over the years he has used or had extensive experience of every type of tweeter you can think of - dome, ribbon, planar magnetic, horn loaded compression driver, AMT, electrostatic, plasma et al - and he considers the SBA Be tweeter to be the best he has ever heard. Just thought that was worth recounting FWIW.

[Toppsy]

Sounds like congratulations are in order Colin in relation to your new speakers, I’d love to hear them sometime.

Hi Ian, You have PM. Of course you are most welcome to pop over for an extended listen.

Many thanks for the congrats.

The whole reason for designing and building these beasts was to go out with a bang and end up with a pair of speakers that would outperform my Edingdale GT speakers. To me this was perceived as a tall order and a really big challenge. However as I have reported in earlier postings these speakers would not have come out so good as they have without the help of some the forum more knowledgeable members who I owe a big debt of thanks. The latest round to tweaks, carried out by Chris and Scott, especially to the passive midrange XO circuit elevated the performance quite some.

I have to agree the performance of the SBA Beryllium Dome tweeters. They are rather special. What I love about them is with a properly designed XO they can be crossed over quite low (as low as 1.5kHz) without any signs of distress or breakup. So you get the full benefit of the stress free sound these produce. With some tweeters when you crank up the volume they can become shouty and fatiguing over long periods of continuous listening. Not so these tweeters. They simply just get louder. The downside to knowing this is it perhaps on occasion encourages one to up the volume perhaps more then one should.

Looking forward to meeting up and spending the day listening to tunes and the like.

[iansr]

Thanks Colin.

[iansr]

First off, a big thank you to Colin for inviting me over to listen to these speakers and for being a splendid host. After chatting about the drivers and the construction of the cabinets I sat down for a listen. I was immediately struck by the purity and transparency of the midrange and treble - I commented to Colin that it was ESL-like. (I owned Quad 989s for several years so I’m in a good position to know.). This is pretty special in a box speaker in my experience and I think its down to 2 things: 1) The SB Be tweeter has got to be one of the best currently available. 2) Using 14 drivers to handle the mids means that each one is barely working and that results in negligible distortion. As I mentioned to Colin, this is not dissimilar in principle to horn loading in that the increase in sensitivity means that the driver doesn’t have to work as hard to achieve the desired SPL and so distortion is reduced. However no horn is ever going to match 14 drivers in those stakes!

Colin and his collaborators should be proud. I’ve been to the Munich show and I can tell you that these speakers would embarrass quite a few so called hi -end offerings.