Wavecor Ardent Metric Drawings - PLEASE!!!!

[Markcsa]

Hi all! Does anyone perhaps have metric drawings or a 3D model they could share? It would be greatly appreciated and save me a lot of cash!

[JonMarsh]

What CAD tools do you have? While the models were created nominally in imperial, creating a set of drawings with Metric annotation is certainly feasible. It might even be possible to import STEP or SolidWorks into Shapr3D and have it do the annotation conversion directly from the original 3D, but that's just speculation on my part- the certain way to do it would be to create drawings with annotation notes.

What's your timetable? I've had a lot of stuff going on this month, including extended family emergencies, so I'm not operating at "peak throughput"!

[JonMarsh]

Some questions and some information to share...

• What is your fabrication workflow and how does a metric solid model or drawing figure in to that?
• What computing platform are you working on and what programs are you using?
• Are you doing this work or hiring someone else to do it?
• If solid model, what exchange formats can you handle?
• If you are working with a solid modeling program, which one?
• Does it have the ability to import a model with one measurement system and convert dimensions to another?
• How are the cabinet parts going to be fabricated? By manual DIY, or are you planning to use a CNC platform of some type?
• Do you have the PDF sheet part collection for the Wavecor Ardent, or the PNG file collection? Both available in ZIP single file, around 5MB. Can be emailed, Apple Messages is faster and easier for large files.
• Have you already purchased the drivers? Two are difficult to obtain, for all practical purposes discontinued by the manufacturer- that is the Wavecor woofers themselves (I have one set left new in box) and the C79 Accuton midrange is not available through their normal distributors in North America.

I have three "model" configurations, all parts in the model, one shows the front panel parts individually and facilitates creating 2D drawing of the panel which is glued up, and then cut with the final facets. One shows a lot of the assembly hardware proposed. The colors designate different materials for the front panel pieces. Recommended is something like bamboo plywood for the outer layers, cabinet grade MDF or BB Ply for the inner two layers.












Be aware that here in the US you can get Steve Manning to fabricate cabinet parts or complete cabinets- he is close to finishing the setup of his new larger facility in Maryland. You might want to PM him for more details.

Contact me or post here about getting the files I can provide, but please review the basic questions above.


~Jon

[Markcsa]

Hi Jon,

Thank you very much for giving up your valuable time to reply to my request!!!! Greatly appreciated!

I have a company that makes process equipment for the mines and we use Autodesk Inventor for our 3D models.

I have a local carpenter that does excellent work and builds a lot of speaker cabinets for the audio community in South Africa, he has a full professional workshop with all the tools, including CNC cutting, etc.
I wish I could get Steve Manning to build me a pair but the shipping costs would kill the project.

To answer your questions:

• What is your fabrication workflow and how does a metric solid model or drawing figure into that? If I had the metric drawings it would just make my life easier. I did start taking the 2D drawings and then added the metric dimensions into the PDF drawings. I think it just creates too many opportunities for my guy to mess it up.
• What computing platform are you working on and what programs are you using? AutoCAD Inventor.
• Are you doing this work or hiring someone else to do it? I am going to hire someone to do it.
• If solid model, what exchange formats can you handle? STEP File, but mostly any format of 3D can be converted, STEP file is one we commonly use.
• If you are working with a solid modeling program, which one?
• Does it have the ability to import a model with one measurement system and convert dimensions to another? Yes, if we have the 3D file, we can convert it to metric.
• How are the cabinet parts going to be fabricated? By manual DIY, or are you planning to use a CNC platform of some type? Mostly CNC where we can.
• Do you have the PDF sheet part collection for the Wavecor Ardent, or the PNG file collection? Both available in ZIP single file, around 5MB. Can be emailed, Apple Messages is faster and easier for large files. I typically use Wetransfer for large files but I will install Apple Messages on my phone and macbook today.
• Have you already purchased the drivers? Two are difficult to obtain, for all practical purposes discontinued by the manufacturer- that is the Wavecor woofers themselves (I have one set left new in box) and the C79 Accuton midrange is not available through their normal distributors in North America. Please see below:

I got lucky!!! A guy on our audio forum is moving into a smaller place and we moving into a smaller home and was selling most of his stash. I managed to acquire 3 pairs of Accuton drivers for very little cash.

They are as follows: C25-6-012 Tweeter, C173-6-090 Mid and C220-6-221 bass.

Now, obviously, I need a second woofer, I am planning on buying a second C220-6-221. I will also need to play with the crossover to accommodate the different bass drivers.

I got very lucky, to buy all the drivers new would cost a fortune today.

I will be building out of BB and MDF but am also looking at HDF for some parts.

Thanking you again for all your help!!

Best regards
Mark Craddock

[JonMarsh]

Well, you're certainly right about getting lucky with the Accuton purchase- their prices have gone up incredibly over the last 3-5 years!

OK, let's see if we can continue and address things in the same sequence- your response answered a lot of key questions, but I'll also have a few comments and suggestions, and some things to look into.

• I use STEP files mainly for interchange, between several programs, including Shark, TurboCAD Pro, Shapr3D, and Fusion360. So getting you STEP files is no biggie. I suggest as I mentioned earlier providing both the detailed initial front panel piece part set, (to make it easier to spec and fab each of the 20mm boards that comprise a complete front panel, as well as the second set which shows the fabrication target with facet bevels. I suggest you PM me with either email address or Apple messages info, I can send either way. Apple messages will handle larger files than email, but of course not everyone uses it! But if you have an iPhone and MacBook, Messages is standard from the factory. You just may not be using it! I send things like 85MB PDF's of my trip travelog to Antarctica, for example.
• The fast way to get piece parts in your situation will be to have the software do the units conversion, then modify the parts per the dimensions of the drivers you plan to use.
• Re drivers, this is interesting- you might want to take a look at the Isiris project, which uses that Accuton midrange driver in the original version. (the update version uses a PuriFi midrange driver). The late version crossover for the original may be a good starting point.
• The Accuton C220 will require some adjustment to the approach- mainly, the differences in T/S parameters mean that it's not suited to a sealed alignment, and should be used ported (from the bottom is probably best) or with PR's on the side. I should be able to find some time later next week to run some sims on that and post back here about what looks promising, but if you are comfortable with that kind of analysis, it can be done readily in VituixCAD or my old favorite, Unibox on Excel. You might end up wanting to increase the internal volume somewhat, for example, making the cabinet deeper.
• Construction materials sound fine; if you have access to HDF that's great, I like it but many folks don't. Keep in mind threaded inserts in ply can be a bit tricky, so choose them carefully. I'll mention here that I'm a fan of certain epoxies for assembly, but what ever you're comfortable and skilled with using should be fine. Only slow set epoxy- none of that 5 minute nonsense. (I'm bad about that, for cabinets I use stuff that has a working life of 30-45 minutes, but for some "specialty work" I like marine epoxies, and others that are formulated like marine epoxy but not necessarily called that- like JB Weld, here; they take 6-8 hours to set up.

PM me with info for transferring files, and I'll get those STEP files to you right away- I can also include a ZIP file with piece part PDFs for reference- all imperial, of course.

[JonMarsh]

One other question- do you have the ability to measure your drivers in the cabinet you build? The baffle dimensions you wind up with impact the half plane launch and SPL for the all drivers, so if you want a sanity check on crossover design, with the right starting basis, that's pretty necessary. The best "budget" system for measurement I know of is probably Pocket Clio. Though I have some pricy microphones and Fuzzmeasurure, I also have Pocket Clio, and it runs on PCs and Macs, though the Mac version is clearly a port over from the PC. There isn't an Audiomatica distributor in South Africa, so if you think that route is interesting, I'd go to their website and look at distributors in Europe.

[Markcsa]

Hi Jon,

Again, thank you for your valuable time!!!!!

I have sent you a PM.

I agree, if I get the STEP file, I will get the drawing program to make the drawing changes to metric.

I have had a long look at the Isiris build, another great project you have done, it may be a great alternative, the Ardent is such an elegant-looking speaker, especially your mahogany build! I would really like to know your opinion on which one sounds better!

I have downloaded all of the speaker design programs that you mentioned and learned how to use VituixCAD, HOWEVER..... I started by copying the crossover circuit from the Ardent and then changing the drivers to the ones that I have. The problem is that I am new to this and have no reference or confidence in my ability to know if I am doing it correctly. I did reach out to two of our local speaker-building experts to ask if I could pay them to modify the crossover design but did not receive a positive response. So, any help in this regard will be greatly appreciated.

We have a local audio forum that I have been active on for a number of years so I know most of the local guys that are experts in this, so quickly running out of ideas. I would spend the effort getting more acquainted with this but I only intend to build one pair of speakers and it is a lot to get into for a one-off build.

To date, I have only ever used MiniDSP for measurements but will buy a CLIO Pocket great device for a reasonably inexpensive price.

I agree with your sentiment regarding marine epoxy, it is the best glue to use.

[JonMarsh]

I received your PM, and have uploaded files on your Drop Box account and have sent via email; after Shapr3D "heals" issues with the 3D models, the STEP files it outputs are more reasonably sized. I imported them into another program just as a check, looks like everything is as expected.

VituixCAD is an amazing, evolving tool, and every time I do a new project I try to remember to donate to Kimmo- thanks to his approach, it's a living, growing, "organism" and very, very capable. Somethings I still like to do with other tools, because of how data and graphs are presented, (enclosure design) But that's just an indicator of how spoiled I have become- for example, I haves many routers, because each one was bought (over the years) because of my perception about how it might excel at a particular task with the right fixtures and bits; so they get set up that way, and put on the shelf to be used for just that task. Over a long period of time, it's possible to indulge habits like that without breaking the bank.

I will run some basic analysis of the Accuton C220 and report on behavior and suggested enclosure alignments.


I do have solid model files for the Isiris, but it is a pretty serious undertaking in construction- another member and friend has recently nearly finished a set of cabinets...

https://www.htguide.com/forum/forum/primetime-a-v/mission-possible-diy/build-stories/926327-dk-isiris-v2-build

and I know of a set built in the Ukraine years ago. Another couple of builds are in early consideration stage, one in Singapore.

Looking at just the crossover, the crossover concepts are relevant considering the C173-6-090, (one of Accuton's absolute best midranges, considering suppression of resonance amplified 3rd harmonic distortion- a problem for several other of their like sized parts) but the differences in baffle width would require adjustments, used in an Ardent style cabinet.


Stay tuned...

[JonMarsh]

I'm going to lead off here with enclosure analysis/synthesis for the Accuton C220-6-221. However, following this I will present a proposal for an alternate woofer solution of the same size and same approximate sensitivity that would "unleash" higher levels of performance in distortion and SPL. The voltage sensitivity of these solutions actually works out to be quite similar, though the impedance isn't. One possibility might be to build the enclosure for the enhanced solution, which would be less than optimum LF extension for the C220, and then upgrade later to the proposed drivers with a new LF crossover to take into account the impedance differences.

Regarding the impedance differences- C220's are not an optimum choice for two drivers in one cabinet- if you parallel them, you get high voltage sensitivity, high enough that finding a midrange and tweeter to work with them could be a challenge; AND you wind up with an LF load of 3 ohms, often less when you take into account the crossover plus drivers. OTOH, if you connect them in series, you wind up with a load around 12 ohms- easy to drive, and a usable sensitivity level (close to 90 dB for 2.83VRMS input) - so that is how I would recommend using them, just like for the original Wavecor Ardent.

The "alternate upgrade solution" would be PuriFi PTT8.0X04NAB-04. Wired in series, these will be right around 8 ohms minimum impedance between 200Hz and 500Hz, verified by my own measurements, which is fairly amplifier friendly and optimizes the power draw for 2.83 VRMS input. (nominal 1W @ 8ohms). Due to how the tradeoffs of T/S parameters and actual impedance works, the net voltage sensitivity is nearly identical- 90 dB for the two PuriFi drivers in series, but an 8 ohm load impedance instead of 12. This is a "good thing" in my opinion.

The other issue is enclosure size optimization- both want more volume than the Wavecor woofers, and need a ported system for LF extension, due to the overall T/S parameters. For the C220, that works out to 80L for a pair; for the PTT8.0X04, this works out to about 60L, though 50L isn't bad either. just not as good. The kicker is that the PTT8.0X04 has nearly double the Xmax, so it's only operating at about half of Xmax for LF output in the 40-50Hz area for 107-108 dB output, whereas the C220 is max'd out.

Data follows shortly.

[JonMarsh]

Now, for the design details and graphs...


Design proposal for best LF extension with C220 Accuton- requires large enclosure volume due to driver parameters.







The plotted SPL response for 1/2 watt per driver:





The SPL response for 10W total, 5W per driver:





The excursion for 5W per driver:






The SPL for 40W total, 20W per driver:





The excursion for 40W total, 20W per driver:

[JonMarsh]

The pervious post shows the limitations that arise with an Xmax of 5mm for this type of driver. Also, this driver does not have special technology to linearize the effective BL versus excursion, so running it at the higher level will degrade distortion performance.

Note, the C220 is effectively an 8-1/2" driver, very similar in diameter to the original Wavecor SW223BD02 and to the PuriFi PTT8.0X04 series.


Now, let's look at my proposal for the PuriFi woofers, which will work well in 60L.





And the related SPL plot for 1W total:




This is fairly close to the voltage sensitivity of the C220, which is 12 ohms nominal in series, versus the PuriFi which are 8 ohms nominal in series.

Now, let's take the drive level up to 50W total, split between the drivers:





And very important, the excursion at this output level:






The PuriFi woofer would be operating at about 1/2 of rated Xmax, and this for a design that highly linearizes the BL force versus Xmax.


Expanding the cabinet design to 60L would be simpler than taking it up to 80L. Fairly similar performance can be obtained with 50L for the dual PuriFi woofers, even less of a modification.

[JonMarsh]

One other thought to toss into the mix...

If I understand you correctly, you currently have two Accuton C220-6-221, and would need to buy two more.

At current US prices, two more (only available on special order- not stocked by Madisound or Solen) would run $1,340 USD.


I think it would really make sense for you to consider going straight to the PuriFi woofers, especially given that they cost a bit less than the Accutons. They are available direct from the web shop at PuriFi-Audio.


https://purifi-audio.com/vare-kategori/transducers/

[Markcsa]

Jon, thank you very much for the drawing files, I did receive them!

That is very interesting. Based on a purely economic viewpoint, the 4 off PuriFi PTT8.0X04 drivers would cost US$ 2 240.00. An additional pair of Accuton C220-6-221 would cost €583.05 or US$ 1 166.00 for a pair.

However, there is the issue of now needing a much bigger cabinet of 80 Litres.

So, now the decision is, do you buy 4 PuriFi woofers and build an Ardent or do you change the drawings and build an 80 L Ardent or do you build an Isiris?

In South Africa, cabinet building is relatively cheap when compared to the USA, for example. This is pushing me towards an Isiris.

BUT... this will then require a different crossover and a full set of drawings. This also costs money.

I think I will spend a bit of time analyzing the options, not an easy decision.

[JonMarsh]

Hello Mark,

I'm going to re-iterate a few points and present another option, if you think an Isiris style cabinet might be a viable option. Of course, this means more charts and graphs... and more time for you spent to analyze the options. But, this is the time to do it, and I'd certainly prefer you proceed on a course of actions with "eyes wide open" and considering all reasonable options.

• First, expanding the Ardent cabinet to 50 or 60L for the PuriFi drivers can be accomplished by just extending the depth of the cabinet at the back- and not as much as you might think, because part of the existing volume is taken up by the midrange sub enclosure and the back of the woofers. Expanding to 80L is possible, but getting a bit weird. Just my subjective opinion. You might want to sketch it out yourself, if you have AutoCAD Inventor, or do a manual sketch with a basic drawing program. I like EazyDraw, use it a lot when I don't need full 3D.
• As noted, for an 8" driver, the PuriFi drivers have a highly linearized motor, and about double the excursion capability, while the way things work out they don't need any more voltage to drive, just more current- a solid 4 ohm capable amplifier.
• While the Ardents are not compact, they're still relatively easy to move around compared with the Isiris, which, the way I build them, is two cabinets, a bass module and the upper range module.
• You could use two Accuton's each in a similarly styled LF Isirs cabinet by reducing the height to 70% of the existing, and keeping the woofers up near the top to maintain the approximate distance to floor
• As the quote from the old Star Wars movies goes, "There is another...." solution. If you think the Isiris is a feasible build for you, then I recommend you strongly give consideration to the LF configuration used in the Isiris update thread, two RSS315HFA-8 woofers per cabinet. Below, I'll present design pages and key performance data for two potential configurations, sealed and vented.
• Why the RSS315HFA-8? I have a "fondness" for LF drivers that successfully straddle the border between subwoofers and woofers. In my mind, that means the driver must have a a significant Xmax capability beyond that of typical woofers of the same size, reasonable impedance curve without excessive rise (I.E., using Faraday rings to control impedance) and should not have a breakup mode near the operating range, and have smooth extended response. The original Aurasound woofers did this, the Wavecor SW223BD02 do this, the PuriFi's do this, and so does this HFA version of the Dayton 12" subwoofer. See the Isirs update thread for plots of it's response in cabinets.
• In the US, four of the RSS315HFA-8 retails for about $1,000. Less than two C220 Accuton's. Shipping will be higher, due to size and weight. There are European vendors for the Dayton drivers.

For reference, the Isiris update thread:

https://www.htguide.com/forum/forum/...1-isirs-update


Fun factoid: in the picture from that thread, of an Isiris next to an Ardent D, the AS168 woofers in the Ardent D now cost about 3x as much as the RSS315HFA-8 woofers.






First up, sealed configuration. That's what I'm running, though I might give thought to updating that- installing a port in the base is not difficult, but then I'd need to redo the cabinet stuffing a bit.






Note, for initial modeling I set things up for power for each driver to produce the same results as for 2.83VRMS drive, which is 1W at 8 ohms, 2W at 4 ohms. So, ~1W per driver.


Sealed SPL:





This is the half plane response; in a listening room, you get LF reinforcement from the boundaries at low frequencies- tuning that is a function of how far you have the speaker from walls.

A simple passive inline filter between preamp and power amp could provide boost for the lowest frequencies, say, if you wanted the half plane response flat to 25Hz or 30Hz BEFORE boundary reinforcement. Something easy to play with, and low cost.


At 100W per driver, output looks like this:





And this is the closed box driver excursion at that power level- pretty reasonable headroom still.

[JonMarsh]

115L is a bit smaller than the optimum vented design, but still fairly usable, and it would be easy to convert the sealed version to this if you wanted to experiment. Note, in this alignment I specify a 10cm ID port tube- this is just big enough to not be a problem with port air velocity in the audible range, but keeps the port resonance up around 400Hz, above the crossover point. A 15cm port is better for port air speed, but drops the port resonance down to about 200Hz, too low. Would interfere with the driver output.


Design work up:






2.83VRMS equivalent sensitivity: (note how this falls in line with the other design options)





Next, the plots relative to 100W/driver, 200W 4 ohm load.





Because of the smaller than optimum enclosure size, the response is "fat" by about 0.8 dB between 40Hz and 65Hz. Many would consider that a "plus", given American tastes.



Excursion is comfortably low relative to driver capability, which means the driver will be operating in a more linear portion of the BL curve even at fairly high output levels:






And port air speed, with 10cm port (down firing, in base of cabinet):

[JonMarsh]

One more brief comment- in my observation of the "speaker marketplace" I'd say that the most successful role for the C220 has been in large multiple-way systems (typically 4 way or more, with an upper midrange and tweeter above and larger woofers below) as the upper bass/low midrange driver, where it's relatively limited Xmax is not a drawback due to the operating frequency range.

[JonMarsh]

One other idea occurred to me later this morning- a "budget" approach so to speak, requiring less investment.

You could build the cabinets with one woofer removed, like the M8ta two way system discussed many years ago- similar style cabinet, and a single Dayton RS225a woofer, which has similar enclosure needs as the Accuton C220, but which does have 40% more Xmax. Then, you could augment that with a subwoofer of your choosing, so that the limitations of the C220 low end were not an issue. You'd want to high pass the 220 three way based system, so as not to over drive it in the low end. You mentioned having some experience with MiniDSP units, so that or an analog electronic crossover might be a possibility.

[Markcsa]

All I can say is thank you very much Jon! You are a very generous man and I really appreciate it!

I am going to build a pair of cabinets and play. I am going to build a Wavecor Ardent and a modified Isis.

I am going to take your advice and buy two pairs of PuriFi PTT8.0X04NAB-04 drivers.

When I build the Ardent I am going to make a plug for the second woofer and have a port that I can block so that I can test the C220 with an adaptor.

I know this is an expensive way to go but it should be fun to play with the options. Will keep you posted.

[JonMarsh]

Hey Mark!

I'm glad you've figured out a way forward that you feel will meet your needs! Keep us abreast of your "adventure" and of course any questions you may have moving forward- we'd love to see how this turns out, but also how the adventure develops!

[theSven]

All I can say is thank you very much Jon! You are a very generous man and I really appreciate it!

I am going to build a pair of cabinets and play. I am going to build a Wavecor Ardent and a modified Isis.

I am going to take your advice and buy two pairs of PuriFi PTT8.0X04NAB-04 drivers.

When I build the Ardent I am going to make a plug for the second woofer and have a port that I can block so that I can test the C220 with an adaptor.

I know this is an expensive way to go but it should be fun to play with the options. Will keep you posted.

It would be great to share your adventure of the build in a thread here on the forum. This is going to be a really fun project to embark on.