Zd5

[cj.9]

Hi,

I'm planning to build the ZD5's soon.
I would like to see others progress or completed photos.
Searched this forum and others but only found a 3 or 4 completed photos.

I haven't decided whether to build the sealed or vented.
Is there any reason to build the sealed instead of the vented?
I ask this because that Zaph's build was sealed.
I did see a post by ZDR that he thought the bass was a little boomy on his vented ZD5's.

I would also appreciate any tips, thoughts or suggestions.

Thanks,

 

[cj.9]

ZD5 Parts List

ZD5 Parts list - Madisound

Not sure if this link works but it's the parts list I've started at Madisound. Most of the list was borrowed from another post.
Link seems to work but have to log into google....

If anyone sees any items that should be changed/upgraded, please let me know.

 

[cj.9]

ZD5 Parts list - better link...

ZD5 Parts List - No Google Login required

 

[Zaph]

Nice list. I didn't even know Google had that sort of online spreadsheet ability.

I think the only thing I'd change would be the damping sheets. That asphalt based stuff smells bad and the solvents in it can occasionally affect the adhesives in speakers.

Rather, I'd use 3 layer Sonic Barrier 1-1/4" on the back, top and bottom, and the 1/2" stuff on the side. Of if you do want more damping ability with the absorption, use the 3 layer 3/4" stuff on the sides but be sure to allow adequate airflow behind the woofer.

I see you've upgraded the large electrolytics to poly. That's a $80 upgrade that won't affect the sound quality much if at all. The world is full of people who think electrolytics sound bad and at least they will think it was a good use of funds.

 

[sdclc126]

Is there anything to be gained by the (claimed?) closer tolerances of poly caps? Should one measure electrolytics to ensure they are acceptably close to claimed values?

 

[Zaph]

Is there anything to be gained by the (claimed?) closer tolerances of poly caps? Should one measure electrolytics to ensure they are acceptably close to claimed values?

Yes, but mostly over time. Electrolytics vary in value over years. If building a speaker I'd expect to own for 15-20 years, I would go with Poly myself in that case.

 

[cj.9]

Thanks for the reply!
Also many thanks for sharing your designs. I'm amazed at the time and energy you put into this hobby.

I updated the list with the damping you suggested.
Also switched back to the Electrolytics, wife was happy to see the cost go down for a change.

I hope to place the order by the end of this week.

I would start the enclosures but I still haven't decided on sealed or vented.

 

[sdclc126]

cj.9 - Do you have a sub, or are you willing to get/build one? Go sealed with sub, vented without.

 

[tomtom]

Hello Zaph

First many thanks for design , second sorry for bad English.

I have some questions about ZD5 design

Do you expect some major improvements when this design was executed with active XO? /just hypothetical active xo with same properties?

Do you heard Dynaudio active monitor bm5a http://www.dynaudioacoustics.com/Default.asp?Id=3680 ?
when yes how do you like it agaist zd5?
/i know its stupid question but this speaker is my two way reference/

It is possible use zd5 for near field monitoring application /say 70cm/

Thank you very very much for sharing your knowledges !

Tomas

 

[sreten]

Hello Zaph
First many thanks for design , second sorry for bad English.
I have some questions about ZD5 design
Do you expect some major improvements when this design was executed with active XO? /just hypothetical active xo with same properties?
Do you heard Dynaudio active monitor bm5a http://www.dynaudioacoustics.com/Default.asp?Id=3680 ?
when yes how do you like it agaist zd5?
/i know its stupid question but this speaker is my two way reference/
It is possible use zd5 for near field monitoring application /say 70cm/
Thank you very very much for sharing your knowledges !
Tomas

Hi,

Chances are high you will get no answer so :

a) No. Even with a correct active c/o improvements are not major.
b) Is a stupid question unlikely anyone has done this ....
c) It is not balanced for near field monitoring. Desk correction is possible.

TBH if you have a pair of BM5a's why would you be looking at ZD5's ?

Nearfield monitors and farfield HiFi speakers most of the time do not
share exactly similar design requirements, but it depends how and
what for the nearfields are used.

/sreten.

 

[tomtom]

Thank you very much for answer! and sorry for continuing little OT

I do not own BM5A i just heard it. /more than briefly/

I own two big system - one 4 way commercial /infinity/ with ribbon upper mid and highs and one DIY open baffle system /PA drivers/ with 18inch bass /sort of magnetar style/. Overal i like OB system more but there are areas where "hifi" style infinity are better.

This was just to - make picture

What i find lately is that most of my listenig isnt in listenig room but in front of my PC while working - so i consider to make or buy some fine nearfield listening system.

Alternatives was ZD5 or those little DA. I heard many nearfield monitor much much more expensive than those DA - including bigger DA from same line - but i like BM5A most. Commercial passive two way are absolutely out of question including DA. /at least what i heard/

These BM5A cost about 1000E /good value for DIY scale also/ so about the price ZD5. /not talking about amp/

Of course easy answer is buy DA and forget about - but there is BUG in my head - what if ZD5 is much better. Unfortunately there is no chance to heard ZD5. I know it use better drivers and has briliant XO - but thats all i know.

Sorry for long story and thanks for comment

 

[sreten]

Hi,

Well unless you like it very loud some very modest speakers would
be fine nearfield at an "all day" listening level. Main issue is the
wanted bass extension at at desk, real bass equals a subwoofer
or possibly active bass EQ given desk space is precious commodity.

Unless your working with sound and have high quality feed from the
PC perhaps you should consider what is really needed at 0.5m - 1m.
Presumably for the former "pro" speakers would be best, for the
latter it is more arguable about the best approach. I'd say small
coherent full range drivers + minisub is the best low SPL approach.

/sreten.

 

[tomtom]

Thank you very much for comment. I appreciate it. Some good points to thinking about.

 

[cj.9]

Do you have a sub, or are you willing to get/build one? Go sealed with sub, vented without.

Yes, I have a sub that could be used.

What I really want to know is which design really sounds the best.

These will probably be the best speakers I will ever have so I don't really want to compromise the sound just for the added low end.
If it sounds just as great with the vented design then that is my preference.
If not then I will be just as satisfied with the sealed, knowing that they sound just as Mr.Krutke intended.

I suppose one option would be build the floorstand enclosure with rear access and be able to reduce the volume by adding a baffle inside.
The dwg. for the floorstand has the port to high to allow adding the baffle. The port would need to be moved down about 2 to 3"s ,i'm guessing.

 

[valleyman]

My preference in this case would definitely be sealed. Sealed enclosures tend to be more precise than vented at the expense of bass. In particular I have heard it said about the ZD5 that the sealed box has notably sweeter midrange. As you have the possibility of adding a sub the lack of bass from the sealed boxes is less of a problem (assuming you can integrate the sub nicely).

In fact I am building a pair of ZD5s in the next week actively driven by lm3886 chips. The electronics is ready to go (thread is in the chip amp section) but I want to build them from birch ply which alas had be ordered from the builders merchant down the road and will be here next friday or so they claim. I'll start a thread in the loudspeaker section next weekend hopefully detailing the construction so I'd be happy to answer any other construction qs you have then. PM me if you like.

Paul

 

[cj.9]

1 vote for sealed....thanks!
Is it always a sacrifice of mids for lows in a vented design?

I placed my order with Madisound yesterday
Still need a few items from Part's Express....we get killed on the shipping to Alaska.

I'll start a thread in the loudspeaker section

This is great! I'm sure others will also be interested in following the construction.

I will be out of town for the next 2 weeks. Hopefully all the parts will be in when I get back. Then I will need to get the mdf or maybe ply.

 

[R-Carpenter]

Yes, but mostly over time. Electrolytics vary in value over years. If building a speaker I'd expect to own for 15-20 years, I would go with Poly myself in that case.

Hi Zaph. It is interesting to me that Madisound has some kind of relationship with you and sell your kits. I spoke with them a few times and they swear that there’s an audible difference between not only electrolytic and poly but also between different brands of polypropylene capacitors. I do tend to agree with your point of view, all though at 1 time I thought I heard a difference between cheap electrolytic and more expensive polypropylene cups. Since Madisound is selling kits based on your design, whats your position on their perspective?

 

[ruerose]

they probably make more money on the poly's

 

[Zaph]

My preference in this case would definitely be sealed. Sealed enclosures tend to be more precise than vented at the expense of bass. In particular I have heard it said about the ZD5 that the sealed box has notably sweeter midrange. As you have the possibility of adding a sub the lack of bass from the sealed boxes is less of a problem (assuming you can integrate the sub nicely).

I have noted how some show a preference for sealed with the ZD5. I suspect it's not really a "sweeter midrange" but a leaner, shallower bass rolloff that emphasizes the midrange a bit more. The sealed system will likely be less sensitive to room size. If you look at an average room response, there's always a primary node somewhere between 50 and 80 Hz depending on room size. The sealed system is rolled off before this, and peaking is minimized as a result. With a little less "room bloom", the midrange probably seems a little more forward and cleaner. The key word is "seems"

Vented will work best in a larger room, or a medium size room that has a reduced bass node via an opening into another large room. My living room connects to my kitchen and dining room via 2 large doorways for example. (all IMHO)

Hi Zaph. It is interesting to me that Madisound has some kind of relationship with you and sell your kits. I spoke with them a few times and they swear that there’s an audible difference between not only electrolytic and poly but also between different brands of polypropylene capacitors. I do tend to agree with your point of view, all though at 1 time I thought I heard a difference between cheap electrolytic and more expensive polypropylene cups. Since Madisound is selling kits based on your design, whats your position on their perspective?

Everyone knows how I stand on high end components including Madisound. While developing the SR71 kit, there was actually a bit of bargaining between what I wanted to be in the kit and what they wanted to sell. There were 2 concessions I made: the Clarity SA cap on the tweeter and the option to get a copper foil inductor on the woofer. The SA cap is a bit more pricey but it's not outrageous. Some people would not buy a steel laminate inductor for fear of "hearing" it. Madisound knows all too well what people want to buy. I didn't complain too much because the kit price knocks 10% off the component costs and people are essentially getting the pricey cap and more for free.

With the kit I'm currently working on for Madisound, it will be interesting to see what we can agree on. With a 2.5-way option and a conjugate impedance notch on the tweeter, there will be some huge caps and coils needed here. We haven't worked out what will be in the kit, but I suspect there won't be any electrolytics in there. While I think electrolytics sound great, someone spending $1500 on a kit isn't going to take the chance. Sure, I've got a big mouth about my beliefs, but I'm no "capacitor nazi" so I don't really care too much what anyone else thinks.

 

[Salas]

Electrolytics can sound good if they are situated away from HF. For example I use a BlackGate red NP in series with my midrange driver, so to avoid the bulk and cost of 150uF of plastic film. I could detect BG's (euphonic) signature until I reversed the parts order and put the coil of the bandpass mid crossover before the cap. That was it, signature gone. Far less HF in the signal so not to excite BG's resonances.