Joey_V
Well-known member
Now I see what kind of craziness you've been up to. 
Apogee Duetta Signature Rebuild
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User211
Well-known member
User211
Well-known member
Now I see what kind of craziness you've been up to.
Yeah a little bit of madness does a wonders for a good old ear massage it would seem.
I'm flat knackered after 4 hours driving and a supposed 2 hour listening session that turned into a 6 hour one
More tomoz
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Joey_V
Well-known member
How big is your room?
User211
Well-known member
Not huge - obviously the room above is not mine, but it has similar dimensions. The speakers are at the wrong end of the room for yesterday's listening session - obviously the door was in the way. About 1 foot behind the right speaker.
So in quite a bit of a sense, that setup is considerably worse than mine, but better in others - further down the room is wider than mine. I think into the French window above mine is 18ft but only 11ft wide. I used to run Ascents in a 28 by 12 room, and I can say for sure they sounded a lot better in the 18 x 11 room. The room I use was designed to be a dinning room, but I moved that upstairs.
After yesterday's session I can state with certainty that the design obviously exceeds the performance of my current Duettas, and that the speaker design is a success. More later when I have some time.
So in quite a bit of a sense, that setup is considerably worse than mine, but better in others - further down the room is wider than mine. I think into the French window above mine is 18ft but only 11ft wide. I used to run Ascents in a 28 by 12 room, and I can say for sure they sounded a lot better in the 18 x 11 room. The room I use was designed to be a dinning room, but I moved that upstairs.
After yesterday's session I can state with certainty that the design obviously exceeds the performance of my current Duettas, and that the speaker design is a success. More later when I have some time.
User211
Well-known member
The system setup was:
JRiver or Qobuz ASIO USB->Lampizator level 4 -> Air Tight ATL-10a passive->Hypex N400 power amp with JFET input stage.
From switch on they sound like Duetta Sigs. The refurbished ones I have now anyway. The better build has resulted in better bass, which was excellent anyway. It is quite noticeable at medium volume and becomes much more obvious when playing loud.
There’s even more clarity at other frequencies too. I wouldn’t be surprised that the max volume a Duetta can achieve isn’t a tad higher now, but I haven’t verified it yet. The torture test of Holden’s The Idiots Are Winning was so clear and dynamic I was gobsmacked, and so was Jon the refurbisher having never heard it. The Hypex modules were capable of playing this with almost as much gusto/dynamics as a Parasound A21 would be in a much smaller more efficient package which is commendable.
I’m sure the uprated x-over is playing a part in providing even more clarity/definition/ resolution. They really are extremely heavy and flooded by potting compound.
It is even harder to determine what volume you are actually running at since the sound seems remarkably similar at mid to high levels. Room effects and trying to talk to someone really gives it away, or looking at bass panel / ribbon deflection but that is unreliable with some material.
In short, the expected gains turned out to be the actual gains. There doesn’t seem to be any downsides I could detect that won’t be cured by more hours on the MRT ribbons. I conclude I am an excellent loudspeaker designer.
The reality of course is I am not. But it doesn’t take much to work or think out a schema or strategy for bracing a frame, making some proper stands and working out how to bond them together in a structurally rigid manner. I’m not pretending I did the hard work. Jon actually implemented it as I asked him to, handling the detail and manufacture. He’s done an excellent job albeit it hasn’t been quick. But everything comes to he who waits, or so they say
Because the Duetta bass panel is capable of genuine low frequency like no ESL I have ever heard is capable of, I am not sure what the effect of doing the same with a pair of CLX would be. You couldn’t brace in the same way, but the current configuration is pretty flimsy TBH. I think a much stronger frame would pay dividends – as Neolith performance seems to suggest with its large panel and excellent frame. But at what cost?
I’m really pleased. I’m also done for loudspeakers for a good long time. Short of building some Duettas out of a solid block of metal I’m really not sure how much further the design can be taken.
When seen in the flesh they look a lot smarter than the camera is picking up. They really do look excellent even though the stands still need a proper polish. I prefer the paint o the Merc blue, which from the pics beforehand I didn’t think I did.
The grey look of the x-over cover is because it is protected by some plastic film. It is actually black. So the black on silver plaque design should look great.
Any future steps forward will be in source components. I’ve done amps big time, tried loads of different ones and I am very happy with the ones I have.
With that I guess this thread is coming to an end.
That means you’re all spared from me ranting on about how good I think these things are. That must surely be a relief. Oh no... wait a minute... Brad's doing some Divas... so maybe more of the same is coming:ROFL:
JRiver or Qobuz ASIO USB->Lampizator level 4 -> Air Tight ATL-10a passive->Hypex N400 power amp with JFET input stage.
From switch on they sound like Duetta Sigs. The refurbished ones I have now anyway. The better build has resulted in better bass, which was excellent anyway. It is quite noticeable at medium volume and becomes much more obvious when playing loud.
There’s even more clarity at other frequencies too. I wouldn’t be surprised that the max volume a Duetta can achieve isn’t a tad higher now, but I haven’t verified it yet. The torture test of Holden’s The Idiots Are Winning was so clear and dynamic I was gobsmacked, and so was Jon the refurbisher having never heard it. The Hypex modules were capable of playing this with almost as much gusto/dynamics as a Parasound A21 would be in a much smaller more efficient package which is commendable.
I’m sure the uprated x-over is playing a part in providing even more clarity/definition/ resolution. They really are extremely heavy and flooded by potting compound.
It is even harder to determine what volume you are actually running at since the sound seems remarkably similar at mid to high levels. Room effects and trying to talk to someone really gives it away, or looking at bass panel / ribbon deflection but that is unreliable with some material.
In short, the expected gains turned out to be the actual gains. There doesn’t seem to be any downsides I could detect that won’t be cured by more hours on the MRT ribbons. I conclude I am an excellent loudspeaker designer.
The reality of course is I am not. But it doesn’t take much to work or think out a schema or strategy for bracing a frame, making some proper stands and working out how to bond them together in a structurally rigid manner. I’m not pretending I did the hard work. Jon actually implemented it as I asked him to, handling the detail and manufacture. He’s done an excellent job albeit it hasn’t been quick. But everything comes to he who waits, or so they say
Because the Duetta bass panel is capable of genuine low frequency like no ESL I have ever heard is capable of, I am not sure what the effect of doing the same with a pair of CLX would be. You couldn’t brace in the same way, but the current configuration is pretty flimsy TBH. I think a much stronger frame would pay dividends – as Neolith performance seems to suggest with its large panel and excellent frame. But at what cost?
I’m really pleased. I’m also done for loudspeakers for a good long time. Short of building some Duettas out of a solid block of metal I’m really not sure how much further the design can be taken.
When seen in the flesh they look a lot smarter than the camera is picking up. They really do look excellent even though the stands still need a proper polish. I prefer the paint o the Merc blue, which from the pics beforehand I didn’t think I did.
The grey look of the x-over cover is because it is protected by some plastic film. It is actually black. So the black on silver plaque design should look great.
Any future steps forward will be in source components. I’ve done amps big time, tried loads of different ones and I am very happy with the ones I have.
With that I guess this thread is coming to an end.
That means you’re all spared from me ranting on about how good I think these things are. That must surely be a relief. Oh no... wait a minute... Brad's doing some Divas... so maybe more of the same is coming:ROFL:
Yes, they're gorgeous.:bowdown:
Whose input stage, Justin? Single power supply per channel or shared?
What's the impedence curve look like for your new toys?
PS: Dark blood red on silver. Think about it.
User211
Well-known member
It's a prototype Hypex amp made by Jon the refurbisher. He knocked up a JFET input stage for it. It is a good amp dunno about the power supply. He's doing a DAC too.
Ken, space isn't blood red. Not sure where you're coming from there?
Impedance is a flat 4 Ohms throughout. None of the ML 1 Ohm(ish) issues at HF
Ken, space isn't blood red. Not sure where you're coming from there?
Impedance is a flat 4 Ohms throughout. None of the ML 1 Ohm(ish) issues at HF
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Artistic license, old bean. What are you, an engineer or something?
If I were still a working stiff and travelling to London regularly, you can bet I'd be knocking on your door for a listen PDQ.
User211
Well-known member
No Sabre ESS solid state output. Tis nearly done.
The amps you can order now . He made some for a customer a while ago.
User211
Well-known member
Nice looking badge Justin but your killing some us here. Play the damn things so you can tell us how they sound.
User211
Well-known member
This here is serious business Brad. I need more time for accurate assessment
User211
Well-known member
This post is mainly for Brad.
The speakers really are heavy. I haven't got them spiked yet because I can't actually tilt the speakers and get the spikes in single handedly. I could do that with ease with the last pair.
Getting them downstairs was close to the limits of two six foot plus men WITHOUT the stands and the MRT assembly. There is a top tip - if you need to move the Divas upstairs take the MID/TREBLE assemblies out first. We had the front covers on but taking that off would obviously help with Divas. It just depends on what you do with the frames/how much weight you add to the speaker.
With my tube amps I can state with certainty that these are somehow easier to drive. I can get higher volume than previously, not that I want it really, but it is there. What this is due to I am uncertain. It may be due to the beefed up construction but the extent of the "driveability" change seems more pronounced than that could account for. The magnets are rated the same - just standard Duetta magnets from an old pair of Duettas.
The MRT ribbon length is now about an inch longer. They are using the ribbon clamps Graz talks about on the Apogee forum. Get some - they clamp the ribbon ends down properly. You might be able to see the difference with shots of the new and old Duettas I have posted. They not only look smarter, but they provide the ribbon with a stable base and better electrical contact I think I was told.
Geometry is important and the geometry of original Duettas/Divas may not have been that great when they left the factory. The steel bars that supported the MRT magnets on my old pair were not completely straight. Lay you mid/HF assembles on a flat surface to see if they are straight. You may well find they aren't!!!
One of the things I asked Jon to take care of was geometry. Everything looks fabulously aligned. The built-in aluminium frame bracing should ensure they stay that way.
I spent about 8 hours in front of them yesterday, and 3-4 hours a night during the week. My advice is to try and implement as many of the design improvements I have listed in the thread. It is impossible with so many changes to know exactly what has had what effect, but the sum of the whole definitely works with the Duetta. It is just a shame Apogee could never build them as well as these have been made. But then again they would have cost a lot more money had they done so.
Subjectively, the speaker sounds like a more accurate affair across the frequency range. Image placement is more precise, especially at volume. Post #286 above is good. I wouldn't want to change anything I have said in it now.
The mid range is somehow less forensic than the last pair. I think it sounds quite notably more natural and refined. This is probably due to a combination of factors not the least being the x-over upgrades, better frames, ribbon terminators, and indeed the current KLM5. It looks somehow better/more consistently crimpled than the last pair. I don't think I have any issues with it i.e. we are not going to have to play with inductors to "get it right". It sounds largely broken in but I think more hours will help to resolve a slightly overly crisp sound at HF. They certainly don't sound like a new ribbon install, which is just plain mad in the first 100 hours IMHO. When they loose a bit of tension I believe they'll be excellent at HF. They are moving visibly less than the broken in pair I had that someone in London now owns. Destined for a Devialet so I hear - which may not be a bad thing. Class D amps I tried with them did OK.
Kedar will determine if they are better than Analysis Omegas. As I told him, they make the Analysis look as though they were built in a junk shop, LOL. I think they are better by a margin, but I'm not sure he'll agree. That said I preferred the old pair to AA as they sounded notably more dynamic/punchy, but I do understand a classical listener preferring the AA to my old pair.
Bass control has entered a different dimension with the beefed up frames at very high volume, but I need to spike the things before I'll really know what is going on here. I'm sure I can hear some "resting on carpet" issues at the moment.
The speakers really are heavy. I haven't got them spiked yet because I can't actually tilt the speakers and get the spikes in single handedly. I could do that with ease with the last pair.
Getting them downstairs was close to the limits of two six foot plus men WITHOUT the stands and the MRT assembly. There is a top tip - if you need to move the Divas upstairs take the MID/TREBLE assemblies out first. We had the front covers on but taking that off would obviously help with Divas. It just depends on what you do with the frames/how much weight you add to the speaker.
With my tube amps I can state with certainty that these are somehow easier to drive. I can get higher volume than previously, not that I want it really, but it is there. What this is due to I am uncertain. It may be due to the beefed up construction but the extent of the "driveability" change seems more pronounced than that could account for. The magnets are rated the same - just standard Duetta magnets from an old pair of Duettas.
The MRT ribbon length is now about an inch longer. They are using the ribbon clamps Graz talks about on the Apogee forum. Get some - they clamp the ribbon ends down properly. You might be able to see the difference with shots of the new and old Duettas I have posted. They not only look smarter, but they provide the ribbon with a stable base and better electrical contact I think I was told.
Geometry is important and the geometry of original Duettas/Divas may not have been that great when they left the factory. The steel bars that supported the MRT magnets on my old pair were not completely straight. Lay you mid/HF assembles on a flat surface to see if they are straight. You may well find they aren't!!!
One of the things I asked Jon to take care of was geometry. Everything looks fabulously aligned. The built-in aluminium frame bracing should ensure they stay that way.
I spent about 8 hours in front of them yesterday, and 3-4 hours a night during the week. My advice is to try and implement as many of the design improvements I have listed in the thread. It is impossible with so many changes to know exactly what has had what effect, but the sum of the whole definitely works with the Duetta. It is just a shame Apogee could never build them as well as these have been made. But then again they would have cost a lot more money had they done so.
Subjectively, the speaker sounds like a more accurate affair across the frequency range. Image placement is more precise, especially at volume. Post #286 above is good. I wouldn't want to change anything I have said in it now.
The mid range is somehow less forensic than the last pair. I think it sounds quite notably more natural and refined. This is probably due to a combination of factors not the least being the x-over upgrades, better frames, ribbon terminators, and indeed the current KLM5. It looks somehow better/more consistently crimpled than the last pair. I don't think I have any issues with it i.e. we are not going to have to play with inductors to "get it right". It sounds largely broken in but I think more hours will help to resolve a slightly overly crisp sound at HF. They certainly don't sound like a new ribbon install, which is just plain mad in the first 100 hours IMHO. When they loose a bit of tension I believe they'll be excellent at HF. They are moving visibly less than the broken in pair I had that someone in London now owns. Destined for a Devialet so I hear - which may not be a bad thing. Class D amps I tried with them did OK.
Kedar will determine if they are better than Analysis Omegas. As I told him, they make the Analysis look as though they were built in a junk shop, LOL. I think they are better by a margin, but I'm not sure he'll agree. That said I preferred the old pair to AA as they sounded notably more dynamic/punchy, but I do understand a classical listener preferring the AA to my old pair.
Bass control has entered a different dimension with the beefed up frames at very high volume, but I need to spike the things before I'll really know what is going on here. I'm sure I can hear some "resting on carpet" issues at the moment.
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User211
Well-known member
The real credit here though goes to Jon for awesome build quality and Graz for awesome ribbons.
Let me take this opportunity to publicly thank the pair of them
Let me take this opportunity to publicly thank the pair of them
JANDL100
Member
I live not that far from Justin in the UK, and I've heard his previous Duettas many times.
He's always said that they were easy to drive, but imo - having heard the speakers on his amps and tried them with several of my own - I think they were a real b*stard! So I'm not surprised by his statement "With my tube amps I can state with certainty that these are somehow easier to drive."
I'm really looking forward to hearing his Interstellas once they are complete and run in for a while.
He's always said that they were easy to drive, but imo - having heard the speakers on his amps and tried them with several of my own - I think they were a real b*stard! So I'm not surprised by his statement "With my tube amps I can state with certainty that these are somehow easier to drive."
I'm really looking forward to hearing his Interstellas once they are complete and run in for a while.
User211
Well-known member
Well you may think that Kedar but I have had 600 Watt amps on them and they aren:t as good as the 211s IMHO. And in the opinion of others.
The Parasound A21 was the best SS option tried I think. But after 6 months I found myself hardly ever using it. So it got sold. For short term demo purposes it really impressed.
The Parasound A21 was the best SS option tried I think. But after 6 months I found myself hardly ever using it. So it got sold. For short term demo purposes it really impressed.
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