Dali Zensor 1 - Please help Reverse Engineer this Crossover?
Hello, I am trying to reverse engineer a Dali Zensor 1 Crossover (Dali part#HS5433).
I would like to get a schematic so I can determine what all of the existing parts are before upgrading my caps or other components. I found an example where someone on an auction site has upgraded their Zensor 1's to Mundorf Caps, Resistors, Coils, etc... however they were selling their upgraded speakers on an auction site and they were not able to share the schematic.
I plan to upgrade the cheap caps first, but I'd like to understand the schematic flow first.
I have attempted to draw up the circuit, but my knowledge is limited and I have not included the image here.
I have also drawn up the parts I know the specs of and included a picture. Here are pictures and the drawing I am referring to.
Any help is appreciated to try to reverse engineer this crossover. Thank you for your help! 🙂
Hello, I am trying to reverse engineer a Dali Zensor 1 Crossover (Dali part#HS5433).
I would like to get a schematic so I can determine what all of the existing parts are before upgrading my caps or other components. I found an example where someone on an auction site has upgraded their Zensor 1's to Mundorf Caps, Resistors, Coils, etc... however they were selling their upgraded speakers on an auction site and they were not able to share the schematic.
I plan to upgrade the cheap caps first, but I'd like to understand the schematic flow first.
I have attempted to draw up the circuit, but my knowledge is limited and I have not included the image here.
I have also drawn up the parts I know the specs of and included a picture. Here are pictures and the drawing I am referring to.
Any help is appreciated to try to reverse engineer this crossover. Thank you for your help! 🙂
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Hi, just disassemble it and re-mount it! I mean, if you just cut the wires and mount a double (4 ) binding posts holder ....plastic ? Naahhhh!!
Then you should be able to make all the adjustments and studies on the circuit without messing all the times in and out of the box.
Generally it's straightforward: the woofer path starts with a coil, the tweeter path starts with a cap. Keep the exiting polarities as they are, you don't want to mess the phase at crossover frequencies. Another step is to make the crossover phisically near amplifier's output, or at least only woofer's inductor and surrounding parts; or just keep the cables short !
Then you should be able to make all the adjustments and studies on the circuit without messing all the times in and out of the box.
Generally it's straightforward: the woofer path starts with a coil, the tweeter path starts with a cap. Keep the exiting polarities as they are, you don't want to mess the phase at crossover frequencies. Another step is to make the crossover phisically near amplifier's output, or at least only woofer's inductor and surrounding parts; or just keep the cables short !
Hi, I saw the pics: probably the only good change would be to change the tweeter cap to a
MKP film part, with a voltage of 250 V. Some would say to change the woofer's inductor too, 'cos the one you have has ferrite core and you would want an air core one.
Also the cement ( ceramic ?) resistors that attenuate the tweeter, I dunno if the 1 $ wirewound resistors would be an " audible" improvement, probably yes.
So, it's a very simple 2nd order filter: you just need a LCR meter to determine inductor's value ( it should be 1-2 mH )
MKP film part, with a voltage of 250 V. Some would say to change the woofer's inductor too, 'cos the one you have has ferrite core and you would want an air core one.
Also the cement ( ceramic ?) resistors that attenuate the tweeter, I dunno if the 1 $ wirewound resistors would be an " audible" improvement, probably yes.
So, it's a very simple 2nd order filter: you just need a LCR meter to determine inductor's value ( it should be 1-2 mH )
Thank you Picowallspeaker 🙂
At a minimum I plan to replace the caps with ClarityCap ESA polypropylene or Mundorf EVO caps, or ?? another reasonably priced option.
If it is recommended, I may build one with higher grade parts such as Mundorf resistors, air coils, etc... I would just point to point solder, but I need to know the schematic first. e.g. what component do I solder to... I am a newbie at reverse engineering these.
Thanks again. I appreciate the suggestions 🙂
At a minimum I plan to replace the caps with ClarityCap ESA polypropylene or Mundorf EVO caps, or ?? another reasonably priced option.
If it is recommended, I may build one with higher grade parts such as Mundorf resistors, air coils, etc... I would just point to point solder, but I need to know the schematic first. e.g. what component do I solder to... I am a newbie at reverse engineering these.
Thanks again. I appreciate the suggestions 🙂
Yes, but how far will the modding take you ?
In ( reverse) order : the "fastons" on the speakers and the connection to the wire ( which wire ?). Is it soldered ? Fastened ? Then the connections to the Xover board...soldered.
Ok, the circuitation is fairly easy, just look at the picture ( just googled " 2nd order crossovers " ) Crossovers - where to start? - Page 2 - Home Theater Forum and Systems - HomeTheaterShack.com
I would focus mainly on preservating the components out of the chaotic environment inside the box, so double binding posts...but...the BP's are just horrible!
In ( reverse) order : the "fastons" on the speakers and the connection to the wire ( which wire ?). Is it soldered ? Fastened ? Then the connections to the Xover board...soldered.
Ok, the circuitation is fairly easy, just look at the picture ( just googled " 2nd order crossovers " ) Crossovers - where to start? - Page 2 - Home Theater Forum and Systems - HomeTheaterShack.com
I would focus mainly on preservating the components out of the chaotic environment inside the box, so double binding posts...but...the BP's are just horrible!
Thank you Lojzek, I really appreciate it! That looks GREAT - so now I need to determine the value of the inductor L1. I am so impressed with everyone's kindness to help me!
I am excited to look in to this. You mention that the boutique parts have low bang for the buck, I am curious if you have a suggestion. I am reading the capacitor thread recommendations at and I am looking at cabinet damping here .
The reference to the auction site (not sure if that is allowed here) that I saw - the mods were very complete including the following. This is going to be way to costly for my budget, but here is an example of mods I saw that someone else did to the Dali Zensor 1 and it piqued my interest.
Which of these mods below have the highest bang for the buck? My current thoughts are to improve the Damping, improve the Caps first.
I see other great suggestions to upgrade the Binding Posts too. Thank you again for all your input!
Removed:
• Polyester damping material removed
• PCB crossover with very basic and very cheap components removed
• Low quality tinned copper internal speaker wire removed
• Removal of the tinned brass push on connectors which were used to connect the speaker driver terminals to the tinned copper wiring
• Brass binding posts removed
Installed:
• 4mm bitumen panels placed on all of the cabinets internal surfaces
• Rubber compound adhesive applied in variable thicknesses on top of the 4mm bitumen panels
• 30mm pure lambswool sheets applied onto the rubber compound adhesive
• CMC 24KT direct gold plated, pure copper binding posts
• Neotech 18AWG solid core 99.99999% (7N) pure OCC copper with solid Teflon insulation
• New 'Point to Point' soldered crossover on a 18MM MDF board
• Crossover board is suspended and isolated from the cabinet using 3M VHB foam
• All components on the crossover are also suspended and isolated from the cabinet using 3M VHB foam and Loctite Silicone
• Mundorf 'M-Cap' Supreme capacitors used exclusively
• Mundorf 'M-Resist' Supreme resistors used exclusively
• Mundorf Supreme Copper Foil Inductors used exclusively
• Mundorf Supreme Silver/Copper/Gold solder used to connect all crossover components, wiring, binding posts and speaker driver terminals. (This is the very best quality solder you can buy! It contains 9.5% Silver, 1.8% Copper and 0.1% Gold).
• 6 X 'Isolate It' 70 durometer sorborthane rubber feet placed on the bottom of each cabinet to provide total isolation and vibration absorption.
I can tell you what I do when I have the chance to do a modification
of a commercial loudspeaker.
First I do a series of spl and impedance measurements. After that I
can tell if there is any room to improve acoustical and electrical
properties. I don't exchange wires if the wires are of decent diameter,
I don't exchange caps unless a different value is needed, the same for
inductors and resistors.
The removed and installed list sounds like a bunch of salesman talk.
Panel damping makes sense if there is obviously something wrong
with the cabinet. I had only once detected an occasional panel buzzing
as loud as music that played.
of a commercial loudspeaker.
First I do a series of spl and impedance measurements. After that I
can tell if there is any room to improve acoustical and electrical
properties. I don't exchange wires if the wires are of decent diameter,
I don't exchange caps unless a different value is needed, the same for
inductors and resistors.
The removed and installed list sounds like a bunch of salesman talk.
Panel damping makes sense if there is obviously something wrong
with the cabinet. I had only once detected an occasional panel buzzing
as loud as music that played.
I'm assuming that you want to upgrade the caps because some aspect of the sound seems lacking?
Upgrading caps is very controversial. Some manufacturers such as YG, Sonus Faber etc. use $$$ caps but there are others such as Revel and KEF that would surprise you with their cap selection. A quick search on Google images for "revel crossover" might be enlightening. I'm not convinced that cap choices make or break a design although there are many people on this forums who would probably disagree and cite the Clarity Cap whitepaper and an instance where they changed caps and noticed a huge improvement. My hearing is what it is and all I'm saying is that, with some not extremely rigorous(I didn't measure the caps to confirm exact values) A-B testing between Jantzen, Dayton and Electrolytic caps, I wasn't convinced it was money well spent.
If you're dead set on upgrading caps for whatever reason, maybe just because it seems like a great project, nice! Humble Homemade Hifi is probably a great place to start.
Can you help us by posting your hand drawn circuit diagram though. I'm having trouble matching the 1st picture with the rest. I'm going cross eyed trying to work out where the cored inductor lead, traces to.
Stereophile has also done measurements for you:
DALI Zensor 1 loudspeaker Measurements | Stereophile.com
Frankly, the crossover seems pretty well engineered and you may (or may not) be better off selling the speakers second hand and upgrading to something you really want, if it's a sound quality issue. Fixing that 2db suckout which may not be very audible will probably require a crossover redesign and will likely involve some tradeoffs.
That said, there are cabinet resonances and a rise in tweeter response that could be improved without too much effort. A series notch filter could drop the treble by 3db, although you'd have to keep an eye on the impedance curve. If you don't want to do any measurements or modelling, you could probably play around with a small selection of inductors, caps and resistors to fit one based on the Stereophile measurements. (warning about impedance again) Fiddling with the cabinet involves playing around with damping and potentially even mass damping, but that's a bit involved.
I'm not sure how much more can be eeked out from the Zensor 1 by fixing the damping issues or even flattening the response though. It's a well engineered product that doesn't appear to be held back by any one particular flaw. However, I still encourage you to go rebuild the crossover and not be put off by my perhaps, not entirely encouraging words. There is an aspect of DIY audio completely unrelated to sound quality, fidelity, etc. - Knowing that you improved something with your hard work!
As far as which of those mods you suggested above will result in the most improvement, damping will probably change the sound quality the most. Note* It is possible to overdamp. I'm not sure I could hear the difference made by the rest of those mods in a blind test.
Upgrading caps is very controversial. Some manufacturers such as YG, Sonus Faber etc. use $$$ caps but there are others such as Revel and KEF that would surprise you with their cap selection. A quick search on Google images for "revel crossover" might be enlightening. I'm not convinced that cap choices make or break a design although there are many people on this forums who would probably disagree and cite the Clarity Cap whitepaper and an instance where they changed caps and noticed a huge improvement. My hearing is what it is and all I'm saying is that, with some not extremely rigorous(I didn't measure the caps to confirm exact values) A-B testing between Jantzen, Dayton and Electrolytic caps, I wasn't convinced it was money well spent.
If you're dead set on upgrading caps for whatever reason, maybe just because it seems like a great project, nice! Humble Homemade Hifi is probably a great place to start.
Can you help us by posting your hand drawn circuit diagram though. I'm having trouble matching the 1st picture with the rest. I'm going cross eyed trying to work out where the cored inductor lead, traces to.
Stereophile has also done measurements for you:
DALI Zensor 1 loudspeaker Measurements | Stereophile.com
Frankly, the crossover seems pretty well engineered and you may (or may not) be better off selling the speakers second hand and upgrading to something you really want, if it's a sound quality issue. Fixing that 2db suckout which may not be very audible will probably require a crossover redesign and will likely involve some tradeoffs.
That said, there are cabinet resonances and a rise in tweeter response that could be improved without too much effort. A series notch filter could drop the treble by 3db, although you'd have to keep an eye on the impedance curve. If you don't want to do any measurements or modelling, you could probably play around with a small selection of inductors, caps and resistors to fit one based on the Stereophile measurements. (warning about impedance again) Fiddling with the cabinet involves playing around with damping and potentially even mass damping, but that's a bit involved.
I'm not sure how much more can be eeked out from the Zensor 1 by fixing the damping issues or even flattening the response though. It's a well engineered product that doesn't appear to be held back by any one particular flaw. However, I still encourage you to go rebuild the crossover and not be put off by my perhaps, not entirely encouraging words. There is an aspect of DIY audio completely unrelated to sound quality, fidelity, etc. - Knowing that you improved something with your hard work!
As far as which of those mods you suggested above will result in the most improvement, damping will probably change the sound quality the most. Note* It is possible to overdamp. I'm not sure I could hear the difference made by the rest of those mods in a blind test.
Hi,
I'd change the 5.6uF to a foil type, that is it.
No point upgrading a cap with 2R2 in series.
Damp the cabinets and properly rewire.
rgds, sreten.
I'd change the 5.6uF to a foil type, that is it.
No point upgrading a cap with 2R2 in series.
Damp the cabinets and properly rewire.
rgds, sreten.
Thank you Sreten -
Sorry, newbie here.
* What does this mean "No point upgrading a cap with 2R2 in series." are you suggesting that I not upgrade the Woofer cap 6.8uF because there is resistor in series?
* Damp cabinets - I removed the "fabric store" damping materials already. I am still researching options. Seems many like blackhole 5, but it is hard to find.
Will you please clarify "properly rewire" - do you recommend that I remove the existing speaker connectors from the crossover and re-wire with 14g or 16g wires directly to the speaker terminals? They are currently 18g wires.
Thank you cocoapuffs for your reply - fellow Washingtonian here 🙂
I am familiar with the Stereophile review of these speakers, I have owned Dali Evidence 370 speakers and Suite speakers for several years. I LOVE them!
I am quickly learning that this "hobby" can become very involved! I am not planning to measure or model and get overly technical, I am just looking forward to a project to attempt to improve the sound and learn something along the way. Maybe it won't make a clearly audible difference, but I might feel the satisfaction of tearing down my brand new speakers and putting them back together again... 🙂
I am familiar with the Stereophile review of these speakers, I have owned Dali Evidence 370 speakers and Suite speakers for several years. I LOVE them!
I am quickly learning that this "hobby" can become very involved! I am not planning to measure or model and get overly technical, I am just looking forward to a project to attempt to improve the sound and learn something along the way. Maybe it won't make a clearly audible difference, but I might feel the satisfaction of tearing down my brand new speakers and putting them back together again... 🙂
I think you should proceed with your plans - if for no other reason than to learn what the various bits do and how it effects the sound of the speakers.
That particular list of mods is, in general, complete and utter overkill, whereby it seems that the basis of choice was solely placed on what was the most expensive components that could be bought.
That said, I believe that you will get definite improvement with some additional cabinet damping or bracing, replacing both the caps with good-quality film, (I believe there is no place for an electrolytic in a crossover) and replacing the woofer coil with an air-core.
My $0.02
That particular list of mods is, in general, complete and utter overkill, whereby it seems that the basis of choice was solely placed on what was the most expensive components that could be bought.
That said, I believe that you will get definite improvement with some additional cabinet damping or bracing, replacing both the caps with good-quality film, (I believe there is no place for an electrolytic in a crossover) and replacing the woofer coil with an air-core.
My $0.02
Thanks 6L6,
I am getting ready to order some dampening now. Looks like the No Rez is available from gr research, I can't find the blackhole 5 for a reasonable price.
As for the caps, I am tentatively planning to go with clarity caps.
I tried to measure the existing woofer inductor with my Fluke 87, but it doesn't measure it. I guess I need to remove it from the board first?
Thanks for the encouragement!
I am getting ready to order some dampening now. Looks like the No Rez is available from gr research, I can't find the blackhole 5 for a reasonable price.
As for the caps, I am tentatively planning to go with clarity caps.
I tried to measure the existing woofer inductor with my Fluke 87, but it doesn't measure it. I guess I need to remove it from the board first?
Thanks for the encouragement!
Hi,
If you want to replace the bass cap, go for the cheapest film type,
there is utterly no point of anything better with 2R2 in series,
and the fact its in parallel (with the 2R2) with the driver.
A big air core on the bass is expensively pointless.
FWIW its a laminated iron core type not a ferrite type.
Rewire if you want, doing it properly is a matter of opinion.
rgds, sreten.
If you want to replace the bass cap, go for the cheapest film type,
there is utterly no point of anything better with 2R2 in series,
and the fact its in parallel (with the 2R2) with the driver.
A big air core on the bass is expensively pointless.
FWIW its a laminated iron core type not a ferrite type.
Rewire if you want, doing it properly is a matter of opinion.
rgds, sreten.
A cheap solen cap on the tweeter will see all the improvement that's worthwhile, if we're talking bang for buck. If the caps aren't well matched it'll sound bad though anyway.
If you're approach is simply to gain a cost effective improvement on sound, this entire endeavour is a folly.
If you want to learn about how speakers work and possibly improve the sound, you'll have a lot of fun but it'll cost you more than the final sound improvement is worth, pretty much guaranteed.
I saw the listing you refer to, the seller was a fool.
That's not to say you can't have fun and enjoy playing with these as a learning experience
If you're approach is simply to gain a cost effective improvement on sound, this entire endeavour is a folly.
If you want to learn about how speakers work and possibly improve the sound, you'll have a lot of fun but it'll cost you more than the final sound improvement is worth, pretty much guaranteed.
I saw the listing you refer to, the seller was a fool.
That's not to say you can't have fun and enjoy playing with these as a learning experience
I should also point out that I have 3 sets of DIY speakers in my current array, which have completely replaced all my previous existing speakers, with the exception of the zensor 1. The zensor is a superbly engineered speaker and sounds superb for its cost, it is one of the classic examples of why diy is pointless as a cost saving exercise. You only save moneyvif you go up against true high end, and then your engineering skills need to be able to match it as well.
Thanks for your input and suggestions. If nothing else, I am excited to learn something along this journey. If the sound improves - I am happy, if not, I am still happy that I learned something.
Here's a brief status update:
* I ordered No Rez for the cabinets, spendy but simple. If I need more fill I will experiment later with Ultratouch Denim insulation from Home Depot (inexpensive and free delivery)
I decided I wanted to purchase caps that were reasonably priced, and reasonable quality. I reviewed feedback from Humble Homemade Hifi and other sites as noted in the beginning of this thread. I chose Claritycaps because of the value and they come is lower voltage (not so large).
Other caps such as the Audience Auricap MKP were strongly considered, but they did not have the exact uf replacement for BOTH. I would have needed to purchase multiple caps put in parallel to achieve my desired size (for the 5.6 which was most important to me). Since the PCB is very limited in size and since I am a newbie I decided to keep my first mod as simple as possible.
* I ordered 1 uf 5.6 and 1 uf 6.8 ClarityCap ESA Range Polypropylene Capacitor 250V
It will take a while before I receive and assemble it, I will post an update afterwards.
Cheers! Thanks again!
Here's a brief status update:
* I ordered No Rez for the cabinets, spendy but simple. If I need more fill I will experiment later with Ultratouch Denim insulation from Home Depot (inexpensive and free delivery)
I decided I wanted to purchase caps that were reasonably priced, and reasonable quality. I reviewed feedback from Humble Homemade Hifi and other sites as noted in the beginning of this thread. I chose Claritycaps because of the value and they come is lower voltage (not so large).
Other caps such as the Audience Auricap MKP were strongly considered, but they did not have the exact uf replacement for BOTH. I would have needed to purchase multiple caps put in parallel to achieve my desired size (for the 5.6 which was most important to me). Since the PCB is very limited in size and since I am a newbie I decided to keep my first mod as simple as possible.
* I ordered 1 uf 5.6 and 1 uf 6.8 ClarityCap ESA Range Polypropylene Capacitor 250V
It will take a while before I receive and assemble it, I will post an update afterwards.
Cheers! Thanks again!
In that case, enjoy yourself, and let us know how it goes.
Probably worth investing in a few 1uF caps as well so you can experiment in parallel and hear the difference.
Also buy an LC meter, there's cheap accurate options available recommended to me by other forum members that have proved to be indispensable;
LC100-A High Precision Digital Inductance Capacitance L/C Meter new | eBay
LC100-A, you'd have to spend thousands to get more accurate, and it's a quick easy way to make sure what you're using is matched.
For the financial investment vs long term use there's no question, getting into this hobby I see it as an essential buy
Probably worth investing in a few 1uF caps as well so you can experiment in parallel and hear the difference.
Also buy an LC meter, there's cheap accurate options available recommended to me by other forum members that have proved to be indispensable;
LC100-A High Precision Digital Inductance Capacitance L/C Meter new | eBay
LC100-A, you'd have to spend thousands to get more accurate, and it's a quick easy way to make sure what you're using is matched.
For the financial investment vs long term use there's no question, getting into this hobby I see it as an essential buy
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