Eraudio Minipanels 505 - Entry Level my foot.

[Nigel]

No, Tom,  the treble section is full range, the side sections have some top end removed. I can'tr imagine how you mght get those graphs and not object to the sound,

I am about toe reconfigure my big panels into their final config (yeah right)  and brought out the minipanels again.

I am disturbed by how good these little panels are.  The big panels will go louder cleaner, but at normal levels and in every other regard the minis are better.

I can't believe I'm saying that. after all the hours customising the very good ESL3s.

[NADMAD]

That’s a very valid point. Anyway, they sound great so all is well. I may or may not have told a particularly fastidious friend that my speakers were the best sounding speakers in Australia... [emoji848]

I only have his Quad 21L floorstanders to compete with so I’m quietly confident

[Nigel]

Tom, Do you know how many people here on SNA have the best system in the world ?....   nor me... but I have witnessed some excellent systems that approach the same goal ("my god, the band is here in the room"), all with differing ways of getting there, all measured/tuned for the room, but as systems get betterer and betterer, it almost seems they lose their noticeable artefacts (aka distortions of the truth). Their delivery of freqs 20-20k is so correct that after a while, they seem to be almost "ordinary".

 

I think your system is the best in the world. I have made it my goal to travel the corners of the globe to prove it....and test the local wines of course...

[robmid]

After following this thread I am very temped to build a pair of 505's with sealed bass unit and have spoken to Rob.

I have auditioned some rebuilt Apogees a couple of times at a QAC GTG's and am in love with the purity of ESL sound.

Currently I am running a pair of LS50's with an 8 inch REL sub in a small room and to me, the sound is superbly dynamic, exciting and transparent but it doesn't have the same refinement as ESL's.

Has anybody compared the 505's with LS50's and how do they compare with used Maggie MMG's?

I normally listen at 70 to 75dB.

Anybody in SE Qld who would be willing to let me have a listen?

Thanks.

Cheers,

Rob

Edited November 22, 2017 by robmid

[Al.M]

1 hour ago, robmid said:

After following this thread I am very temped to build a pair of 505's with sealed bass unit and have spoken to Rob.

I have auditioned some rebuilt Apogees a couple of times at a QAC GTG's and am in love with the purity of ESL sound.

Currently I am running a pair of LS50's with an 8 inch REL sub in a small room and to me, the sound is superbly dynamic, exciting and transparent but it doesn't have the same refinement as ESL's.

Has anybody compared the 505's with LS50's and how do they compare with used Maggie MMG's?

I normally listen at 70 to 75dB.

Anybody in SE Qld who would be willing to let me have a listen?

Thanks.

Cheers,

Rob

Apogee is a ribbon plannar design and not an electrostatic loudspeaker (ESL). The panel in a ribbon speaker design has closely laid ribbon coils on the membrane and magnets positioned close to them passively driven similar in the way a normal speaker cone and magnet driver operates except that it is laid out on a flat panel membrane. Whereas an ESL has metallic paint on the whole membrane and there is high voltage charge applied in place of the magnets to propel the membrane.

 

In what ESLs do best (imaging, detail, holographics, voice) they generally do it better than most ribbon panel speakers, whereas ribbon panels are somewhere between conventional cone box speakers and ESLs and can be driven louder.

 

I have both Rob’s 505 ESL and Kef LS50.  I really like the Ls50 but they are no where near as good as my old Acoustat ESLs or Robs 505s in what ESLs do best. The LS50 have about the best imaging, voice coherence and holographics in terms of a cone driver box two way bookshelf speakers in that price range and well above. The treble in the Ls50 is adequate but not as good as say Dynaudios, Jamo Concert 8 or Lenehans that have dedicated large and high spec tweeter unit assemblies.

Edited November 22, 2017 by Al.M

[Sub Sonic]

@robmid, you won’t regret purchasing a pair of Rob’s 505 panels. Highly recommended.

P.S. The reason I’ve been silent on this thread for so long is that I’ve just been listening to the music through them, and forgetting about the equipment :-)

 

Regards,

 

Matt

[robmid]

Thanks for confirming my understanding.

I'm sure they are exactly what I am after, I'll order a kit today.

Cheers,

Rob

[andyr]

8 hours ago, Al.M said:

Apogee is a ribbon planar design and not an electrostatic loudspeaker (ESL).

 

Correct.

 

8 hours ago, Al.M said:

 

The panel in a ribbon speaker design has closely laid ribbon coils on the membrane and magnets positioned close to them passively driven similar in the way a normal speaker cone and magnet driver operates except that it is laid out on a flat panel membrane.

 

 

That is not a correct description of a Magnepan (planar) speaker.  Maggie drivers can be divided into 4 types:

1. panel drivers which have round aluminium wire glued to a mylar sheet, with strip magnets placed on one side of the mylar.
2. panel drivers which have ~1/8" aluminium ribbon (Magnepan calls this 'quasi-ribbon') glued to a mylar sheet, with strip magnets placed on one side of the mylar.
3. either of the above, with magnets placed both sides of the mylar ("push/pull", to better control panel excursion and reduce distortion).
4. a pleated ribbon about 1/4" wide, suspended between 2x strip magnets (this is the "true ribbon" tweeter on the 3-way models).  The magnets are at the 2 edges of the ribbon (not at the back or front) and the ribbon is secured with dobs of glue at the sides, about every 2".

 

Regards,

Andy

 

[tesla13BMW]

What are peoples recommendation for a matching woofer for the 505's?  Note: Definitely stacked two high and possibly three.

 

Yes, how longs a piece of string!  Just to get down low enough for Jazz double base at comfortable listening level in a 6m x 9m room, listening across the short distance.

 

Would be looking at open baffle in a U frame for ease of construction.  But, not limited to this idea.

 

Feel free to PM if its more comfortable 

[NADMAD]

25 minutes ago, tesla13BMW said:

What are peoples recommendation for a matching woofer for the 505's?  Note: Definitely stacked two high and possibly three.

 

Yes, how longs a piece of string!  Just to get down low enough for Jazz double base at comfortable listening level in a 6m x 9m room, listening across the short distance.

 

Would be looking at open baffle in a U frame for ease of construction.  But, not limited to this idea.

 

Feel free to PM if its more comfortable 

This is what I did and it works amazingly well. Panel mounted centrally over up-firing Morel 10” woofer in a sealed cylindrical 40l enclosure. The integration is seamless to my ears and because the cabinet isn’t ported the woofer can keep up with the panels, so you don’t suffer from “lazy bass”!

[Rob181]

WOW...now that looks sensational...

Upward firing woofers is also what Ambience use with their "true ribbon" tweeter/midrange...well most of their range use upfiring woofers anyway...

Edited November 23, 2017 by Rob181

[Sub Sonic]

@NADMAD what crossover point and slopes did you end up using? I lost the MiniDSP setup in mine after a room change around a couple of days ago and everything sounds different. Will be playing with setup again, but currently around 320hz, LR24. Some EQ applied also, mainly to 8” woofer in undersized box, which hands over at around 80hz to Rhythmik subwoofers. More work is required on the woofer side of things, or perhaps a change from the 8” woofer to a 6”...

 

Regards,

 

SS

[NADMAD]

5 hours ago, Rob181 said:

WOW...now that looks sensational...

Upward firing woofers is also what Ambience use with their "true ribbon" tweeter/midrange...well most of their range use upfiring woofers anyway...

Thanks Rob! I plan at some stage to make them again because I kind of designed as I went along and I think they could be aesthetically refined a bit - the woofer enclosures are quite a bit bigger than they need to be. That being said quite by accident I made the most childproof speakers I could have done! No accessible cones to push in (he did both woofer and tweeter on my NS10s, sob), voltages safely tucked away, solid oak panel frames and they weigh circa 60kg each so my 18 month old could swing off them and they wouldn't move!! I also bought a lethally massive rounder router bit so no sharp edges to head but!

Finally, with regards the woofer I consulted a good friend and guru on the matter and he advised me that mounting centrally would work well because both sides of the panel see the same pressure from the woofer so it balances out rather than being blown around as would be the case if the woofer was offset. Interestingly though Acoustat offset their woofers, probably for reasons of aesthetics. 

[NADMAD]

5 hours ago, Sub Sonic said:

@NADMAD what crossover point and slopes did you end up using? I lost the MiniDSP setup in mine after a room change around a couple of days ago and everything sounds different. Will be playing with setup again, but currently around 320hz, LR24. Some EQ applied also, mainly to 8” woofer in undersized box, which hands over at around 80hz to Rhythmik subwoofers. More work is required on the woofer side of things, or perhaps a change from the 8” woofer to a 6”...

 

Regards,

 

SS

Hey Matt,

 

Here are my settings:

 

Panels: 500Hz, LR24, Low shelf boost circa 400Hz to balance out the response. This has been questioned by a few in this thread but that's what my ears and REW (several measurements) tell me was required. I have performed the measurement with two versions of the 505s and before and after replacing the diaphragms on them with Rob's guidance and got the same results. 

With this boost they sound amazing, and most of it is absorbed by the crossover slope anyway, meaning 6dB max in boost in the net curve. It just changes the slope of the crossover really for a more even response. The only thing I'm doing differently to the others is I don't use the crossover cap on the 505 board.

Woofers: 10" woofers in 40l cabinet, 7dB shelf boost at 31Hz, Crossover 500Hz LR24.

Hope that helps!

Cheers, Tom

[Al.M]

On 23/11/2017 at 12:11 PM, Sub Sonic said:

@NADMAD what crossover point and slopes did you end up using? I lost the MiniDSP setup in mine after a room change around a couple of days ago and everything sounds different. Will be playing with setup again, but currently around 320hz, LR24. Some EQ applied also, mainly to 8” woofer in undersized box, which hands over at around 80hz to Rhythmik subwoofers. More work is required on the woofer side of things, or perhaps a change from the 8” woofer to a 6”...

 

Regards,

 

SS

I haven’t locked mine down with a woofer decided on yet but have several options. It depends on what you think is best match, budget, appearance and configuration. I believe the latest versions have lower crossover that is set but you can adjust that. Most people seem to be using around 400hz crossover give or take so stick around that depending on choice of woofer and setup.

 

The panels are very directional so I would be thinking a forward facing woofer but would be curious to try upward as in one example here. I’ve had several commercial speaker ribbon or ESL hybrids with woofers up or forward and tend to prefer forward as more coherent and bass more impactful.

 

Edit: sorry didn’t read earlier was it you said dipole? Then will need some large woofers perhaps around 10-12 inch. If not dipole and then woofer box then ou have a choice of woofer and midbass options, 5 - 12 inch woofers depending what you want it to be and supported by subs or not, floorstanding or standmount etc from the likes of ScanSpeak, Seas, Accuton, Eton, Peerless, Focal, Morel etc driver makes. Flick thru online the numerous drivers available and investigate further.

 

For inspiration into the types of drivers available and implemented check out this site http://www.troelsgravesen.dk/Diy_Loudspeaker_Projects.htm

 

Something like 2 x Scanspeak Illuminator 18cm drivers in ported cabinet, equivalent Scanspeak 10 inch or Eton 11 inch hexacone woofer might be a start to check out.

Edited November 24, 2017 by Al.M

[NADMAD]

I personally wouldn’t go as small as 5” because the panels go low enough themselves and you’ll end up with the 5” mostly covering ground the panel could do itself, and as a result potentially under utilising the panel.

I would also personally avoid ports because you’ll never get a ported enclosure to integrate properly with an ESL panel, despite what many manufacturers have claimed. There’s way too much delay and way too much hangover for the impulse of both drive units to align.

I spent a small fortune on the Morel drivers because they are constructed to be fast responding. The voice coil is aluminium and is also large so the driving force is distributed as evenly as possible. The magnets are also neodymium/ ferrite hybrids making them good and strong.

Cheaper alternatives will work though. I’d just strongly recommend a sealed enclosure, and use an active EQ to boost the LF.

With regards directionality the 505s are actually pretty good. They are not particularly directional in the horizontal plane because they are segmented so the upper HF is only emitted by the centre strip which is about 35mm wide from memory. 10k and above will be directional but below should be pretty wide in dispersion. Not sure what the roll off frequency is on the side segments but these will start beaming at around 2.5Khz. As long as the roll off is around this area then you should be good.

Vertically it’s a different matter of course which is why I put adjustable feet on mine so I could tilt them back!

[Newman]

On 23/11/2017 at 10:13 AM, NADMAD said:

This is what I did and it works amazingly well. Panel mounted centrally over up-firing Morel 10” woofer in a sealed cylindrical 40l enclosure. The integration is seamless to my ears and because the cabinet isn’t ported the woofer can keep up with the panels, so you don’t suffer from “lazy bass”!

Ha ha, I had to laugh, this is the identical concept, only differing in detail, to my plan that I collected all the parts for about 5 years ago using the UFPS440. Great minds think alike -- but only half of them get off their bums and do anything about it, I see. Well done.

 

 

Edited November 24, 2017 by Newman
layout

[robmid]

I have just ordered a 505 kit from Rob and I am researching woofer alternatives. Rob has some budget 8 inch woofers available for $75 each and he recommends an enclosure volume of 15L and he says the bass perfomance is adequate .

I am on a limited budget so my question is, are there any 'hidden gem' 8 inch woofers out there that might suit for under $150?

Thanks,

Rob

[NADMAD]

Ha ha, I had to laugh, this is the identical concept, only differing in detail, to my plan that I collected all the parts for about 5 years ago using the UFPS440. Great minds think alike -- but only half of them get off their bums and do anything about it, I see. Well done.
 
 

Do it, do it, do it!! You will not be disappointed! I have mine too close to the back wall so built some QRDs and placed them directly behind them. The imagine when listening to the clocks at the start of Pink Floyd’s Time is unbelievable!

[NADMAD]

I have just ordered a 505 kit from Rob and I am researching woofer alternatives. Rob has some budget 8 inch woofers available for $75 each and he recommends an enclosure volume of 15L and he says the bass perfomance is adequate .
I am on a limited budget so my question is, are there any 'hidden gem' 8 inch woofers out there that might suit for under $150?
Thanks,
Rob

Hi Rob, I previously used SB Acoustics 10” drivers that came highly recommended. They were about $200 each so might have a $150 8” option.

[Sub Sonic]

22 minutes ago, NADMAD said:

Do it, do it, do it!! You will not be disappointed! I have mine too close to the back wall so built some QRDs and placed them directly behind them. The imagine when listening to the clocks at the start of Pink Floyd’s Time is unbelievable!

I like the idea, any chance of sharing some details or a website about the build? Mine are currently in a heavily damped sealed enclosure and they sounded really good until I changed the room around. Vaguely thinking about going open again... :-)

 

@Newman the 440s are well worth completing, I had a set before the 505s. The 440s are more directional, but are an awesome sounding panel.

 

Regards,

 

SS

[Red Spade Audio]

On 11/23/2017 at 9:06 AM, tesla13BMW said:

What are peoples recommendation for a matching woofer for the 505's?  Note: Definitely stacked two high and possibly three.

 

Yes, how longs a piece of string!  Just to get down low enough for Jazz double base at comfortable listening level in a 6m x 9m room, listening across the short distance.

 

Would be looking at open baffle in a U frame for ease of construction.  But, not limited to this idea.

 

Feel free to PM if its more comfortable 

 

It all starts with the bandwidth. On the bottom end, you probably want around 40 Hz bass extension. On the top you want at least 200 Hz, possibly higher. You have to consider both. An open baffle with wings to achieve more bass extension before EQ will have limited useful top end.

 

Further, once you get below around 200 Hz, we enter the modal region. A dipole here doesn't eliminate the room issues that dominate. In fact, if you look at a dipole compared to a monopole in the same position, both can suffer modal ringing to the same extent.

 

My suggestion is a fairly conventional monopole (sealed or ported) with a good quality woofer with good midrange extension. 8 - 12" SB Acoustics woofers are a good start for your search.

 

With a U frame, you either end up with making them large or using sub drivers with EQ. Neither are very good compromises where you want to cross at 200 Hz or higher.

 

On 11/23/2017 at 9:43 AM, NADMAD said:

This is what I did and it works amazingly well. Panel mounted centrally over up-firing Morel 10” woofer in a sealed cylindrical 40l enclosure. The integration is seamless to my ears and because the cabinet isn’t ported the woofer can keep up with the panels, so you don’t suffer from “lazy bass”!

Nicely done! Clever use of architrave.

 

I have one of these I never got around to using. Perhaps not quite the same - one of the Involve Audio kits. Out of curiosity I measured it some time ago. The vertical beaming was dramatic but what stood out in my mind was an interesting effect when playing music as the panel was high up on my measurement rig (outdoors). Standing next to the panel in the null, there was a bizarre ventriloquist effect. The sound was bouncing off the nearest wall and it gave the effect of the music coming from a location well beyond the other side of the wall!

[Nigel]

Had a workmate come over for a listen and while he was very complimentary of the speakers, it was after he left that I sat in the chair and picked up a slight harshness near the beginning of Mas Que Nada. I thought maybe it is the recording, maybe it is the minipanels’ intermodulation distortion from being too loud.

So I turned the volume down a tad and restarted the track, and s-w-eet, no harshness. Unfortunately I had to tell my workmate that a lot of the listening session was conducted up at that loud level. My fault, I was trying to demo that despite their size, they can go quite loud, well now I know they sound nicer just down a little bit and to go even louder would require stacking another pair.

 Lesson learnt.

[robmid]

Do you know what sort of dB listening level would would be optimum for 505's? 

 

I normally listen to my LS50's under 85dB (phone app reading) because I have a small room and cancelling at listening position slips in above that.

[Newman]

Do you know what sort of dB listening level would would be optimum for 505's? 
 
I normally listen to my LS50's under 85dB (phone app reading) because I have a small room and cancelling at listening position slips in above that.

Cancellation is volume dependent?