Yes if steeper than 1st order filter is used. High 1st order filter is forgiving because it does not really cause almost any delay.
Here's the step of 40cm elevated listening position, where the step of the Mummy is delayed about just correct and step is perfectly "2-way" ie. you cannot really tell from the step that there are additional bass radiators.
In final tuning I will have to tweak the delay physically a little compared to how they are located now.
The coils you see on the external xo are for Mummys. Thich wire Mungdorfs. The subs are still xo'ed with previously owned coils (6mH Wax coil foil + 3,9mH Mungdorf foil right now).
Single amp passive system in the finale
One sacrifices something to gain something.
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One could argue day 'n' night what is more beneficial. But what's the point if one can afford it
True, I have owned/used dsp with various systems. With subs it could be very beneficial in many situations, but if one can integrate them with 1st order filter and without delay, then you only really lose the peq/level adjustment with dsp and it might not be worth it. Occams razor et cetera.
Single amp system is a great relief compared to multiamp systems with wire spagetti
. Its also the only correct way to listen to different amps' sound. I also build and tune tube amps so I have to have a system that is capable of "error/flavour monitoring" full band. There is also something peculiar how cohesive and "one" passive xoed systems always sound. I got this realization after hearing some of my systems with dsp and with passive xo. I could be happy with both, but they are not apples to apples how they sound imo.
Check out this Glass Swords "Rustie" album, nice wide bandwidth bass in many tracks. Sealed subs generate some mighty pressure transients.
Link (headphones are the best for listening these system videos): YouTube
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Regarding how low can sealed subs go, even when used high eff kick bass drivers, I made a somewhat more "reference" measurement, meaning it tells more of the radiator itself than previous measurements. In this measurement the amp is a transistor amp (but not flat below 20hz). The dac is also transistor now. The pre is still a tube amp (tvc and output transformers).
The mic is also not calibrated so the lows are more attenuated what they should be (attenuation 5-10db at 10hz by looking at uncalibrated ecm8000 responses). But can only quess without calibration.
With transistor amp and dac the low end got boosted almost +20db at 10hz compared to full tube signal path.
With fully dc-coupled signal path and calibrated mic from 5hz upwards, the response would be almost flat all the way down to single digit hertses. This room pressurises more that I had first thought. The culprit was the transformer coupled tubes. They are not used for maximal infra bandwidth anyway
Lower response is just the Mummy main speaker without sub (also sealed).
The mic is also not calibrated so the lows are more attenuated what they should be (attenuation 5-10db at 10hz by looking at uncalibrated ecm8000 responses). But can only quess without calibration.
With transistor amp and dac the low end got boosted almost +20db at 10hz compared to full tube signal path.
With fully dc-coupled signal path and calibrated mic from 5hz upwards, the response would be almost flat all the way down to single digit hertses. This room pressurises more that I had first thought. The culprit was the transformer coupled tubes. They are not used for maximal infra bandwidth anyway
Lower response is just the Mummy main speaker without sub (also sealed).
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^Yep - the room!
Yes they are hORNS/Autotech Mummy.
Original drivers:
BMS 4524: Overview
Beyma 12BR70: https://www.beyma.com/speakers/Fich...hoja-tecnica-baja-media-frecuencia-12BR70.pdf
Current drivers:
BMS 4526HE: Overview
Fane Sovereign Pro 12-500: SOVEREIGN PRO 12-500
I put the 4524's diaphragm into 4526HE motor and changed the Beyma to Fane Sovereign Pro 12-500. I also built the crossovers to be external.
I like this small BMS comp. Hifi sounding comp, even though it's plastic membraned, but the small VC helps. Sounds never harsh in this horn.
The Sovereign Pro 12-500 is also a good sounding and very kicking driver. Also better match sensitivity-wise than Beyma was. It has oversized lower spider suspension and very nice UK made air-dried paper cone without treatments. It was the first inspiration to consider/get 15" Fane woofers also for the subs. I wish it had copper shorts to lift it up to same H3 performance like FC-153F01 has. The original Beyma had rubber surround and (after I opened one) also aluminum voice coil former - I don't miss them.
The box supports almost any round 12" and 1" comp driver. TD-2001 would also fit I presume, would be interesting to test.
4524 vs 4526HE. The 4526HE is a neodymium ring motor instead of ferrite, it has "pressure vents" under the membrane and copper plated pole piece and maybe some other shorting ring also (BMS states "shorting rings").
Yes they are hORNS/Autotech Mummy.
Original drivers:
BMS 4524: Overview
Beyma 12BR70: https://www.beyma.com/speakers/Fich...hoja-tecnica-baja-media-frecuencia-12BR70.pdf
Current drivers:
BMS 4526HE: Overview
Fane Sovereign Pro 12-500: SOVEREIGN PRO 12-500
I put the 4524's diaphragm into 4526HE motor and changed the Beyma to Fane Sovereign Pro 12-500. I also built the crossovers to be external.
I like this small BMS comp. Hifi sounding comp, even though it's plastic membraned, but the small VC helps. Sounds never harsh in this horn.
The Sovereign Pro 12-500 is also a good sounding and very kicking driver. Also better match sensitivity-wise than Beyma was. It has oversized lower spider suspension and very nice UK made air-dried paper cone without treatments. It was the first inspiration to consider/get 15" Fane woofers also for the subs. I wish it had copper shorts to lift it up to same H3 performance like FC-153F01 has. The original Beyma had rubber surround and (after I opened one) also aluminum voice coil former - I don't miss them
.The box supports almost any round 12" and 1" comp driver. TD-2001 would also fit I presume, would be interesting to test.
4524 vs 4526HE. The 4526HE is a neodymium ring motor instead of ferrite, it has "pressure vents" under the membrane and copper plated pole piece and maybe some other shorting ring also (BMS states "shorting rings").
Old pics, but yes they integrate better to subs with port plugs and are still sealed.
Quite good cabinets, non-diffracting edges, no parallel walls, damped with bitumen and felt and the oblate spheroid horn is very good. The looks cannot be easily imitated with diy. They are not Usher D2/D3 but nice for the size and smaller size is mandatory in the current room.
Some burn in for the subs with the borrowed pro amp. Each module has the drivers in opposite phases so they move like in a dipole without air spring and suppress the fundamental. They want some juice to move close to their xmax, the class ab amp runs quite hot even with short CEA bursts.
Link: YouTube
Quite good cabinets, non-diffracting edges, no parallel walls, damped with bitumen and felt and the oblate spheroid horn is very good. The looks cannot be easily imitated with diy.
They are not Usher D2/D3 but nice for the size and smaller size is mandatory in the current room.Some burn in for the subs with the borrowed pro amp. Each module has the drivers in opposite phases so they move like in a dipole without air spring and suppress the fundamental. They want some juice to move close to their xmax, the class ab amp runs quite hot even with short CEA bursts.
Link: YouTube
Subs' location has finally settled at least for now, the 40cm wide "slot" is quite good compromize for a passive setup.
Fired up my CDT-four cd spinner a while ago and have been listening to cd's ever since. File/stream based digital would be much better served from a dedicated streamer than win-computer.
Found a cd including this gem of a song from a local flea market
Video: hORNS Mummy - Sonique - YouTube
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The dog is daddy's good boi. Always resting at my feet. Sometimes behaves quite as chaotic as the electrical coil dynamic animals (in Finnish we call drivers as animals/creatures sometimes). One could say his electric driving impulses are slightly underdamped, Q maybe 1.3. He's name is Sumu, translates to "fog" or "mist".
. Always resting at my feet. Sometimes behaves quite as chaotic as the electrical coil dynamic animals (in Finnish we call drivers as animals/creatures sometimes). One could say his electric driving impulses are slightly underdamped, Q maybe 1.3. He's name is Sumu, translates to "fog" or "mist".
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I'm quessing something around 1uf as I have high input impedance in my amps. Upping the capacitor after some point does not produce lower bass if the primary of the opt is kept as the load.
I might make again the passive output as an option to the second output rca pairs (taking the signal straight after the TVC).
I might make again the passive output as an option to the second output rca pairs (taking the signal straight after the TVC).
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Dear Legis and Pixelplay,I'm quessing something around 1uf as I have high input impedance in my amps. Upping the capacitor after some point does not produce lower bass if the primary of the opt is kept as the load.
I might make again the passive output as an option to the second output rca pairs (taking the signal straight after the TVC).
Great thread, and thanks Legis for all your audio porn pics!
))Would like to ask both of you for advice, am trying to do up a 01a tube DHT preamp (transformer coupled), and going to use finemet output transformers. Was wondering if its a better idea to use finemet chokes or lundahl chokes for it.
And was wondering how much/what kind of improvement in sound quality finemet choke brings to the table? Is it significant? (Finemet costs a lot more
) As for the rest of the transformers is the quality critical? Do i need finemet for them or just lundahl or even lower quality ones are fine?
Thanks so much for your help and advice in advance! (And Legis if you decide to see your dac/preamp one day pls do let me know! I will be first in line
)Thanks!
Regards
Ben