Thiel Owners

Greeting All,

Started reading this thread skipping to January 2018 to present. Having viewed Tom, Beatle, Halco, marqmike and others comments and pictures, my sincere gratitude to all for the great discussion. It’s very enjoyable reading and learning as a CS2.4 owner.

A local audio store, Audioport, introduced me to the 2.4 with Classe Delta back in the early 2000’s. More that could be shared but after several years of enjoying the current setup, with a few changes along the way, it’s time to update. The evolution of this thread with its 2.4 crossover development has drawn the mind multiple directions landing on taking it step by step and a small journey. Each step trying to understand, by ear, what improves and what may be less desirable.

Since 2018, 2.4 specific discussion seemed to touch on:

• Original crossover source (i.e. Lexington, FSB)
• Coax and woofer capacitors, resistors, inductors
• Internal wiring
• Binding posts
• Cabinet considerations such as bracing and fill materials (i.e. fiber, wool)
• External vs internal crossover placement
• Build recommendations such as Masonite, component placement/alignment, and thermal considerations (i.e bluetack)
• Driver source and capabilities

There will be a document posted with pictures and information in case anyone has interest. Hopefully something can be contributed to the discussion. I am open to trying a new path or two along the way.

Progress to date:

1. CS2.4 Serial Numbers 4021 and 4022 original crossovers are exactly the same as marqmikes (https://tinyurl.com/ffcerraa).
2. After a quick exchange with Rob Gillum at Coherent Source Service, a SE upgrade was purchased and installed. Break-in is in progress and will share thoughts in the next week.

Next:

• Mills MRA-12 resistors have arrived. The 4 Ohm is Vishay Mills MRA-12. The 16 Ohm will be parallel 8 Ohm Mills. This change seemed universally agreed on with the option to use Path. As a value buyer and understanding of my listening abilities, using Path resistors would take convincing.
• Move to Masonite? Seems inevitable with future growth. Could save the originals with SE capacitors if someone was interested in them when appropriate to let them go.
• More to come….

Hi @jafant , appreciate the warm welcome and you have been moderating a great topic!  Make any changes to your 2.4 SE's?  I'll share more on musical tastes and system in the next few evenings after work.

Thanks for the correction @vair68robert!  I should have said series (Rt = R1+Rn) vs parallel with just 2 resistors as the site you link pointed out Rt = R1*R2/(R1+R2).  You are right about capacitor sizes which was reenforced looking at @beetlemania crossover pictures.  The switch to Masonite seemed to be required at some point for film capacitors and perhaps even for the resistor switch using the 2 resistors you kindly provided or the 2x8ohm I have.  As @tomthiel said, is "not so simple" and my mind hasn't quite fully realized yet.  Quite a lot to learn. 

Hi @tomthiel, I appreciate the information and clarity.  The project with duramax747 will certainly be of interest as I don't have a clear understanding of the desired end scope.  The new layout scheme, ClarityCap PUR and more learnings along the way would be good to know before going too much farther with the build.  

Frankly, my technical knowledge is being relearned from a job building magnetic card readers for video game arcades back in college 25+ years ago, so it is rusty but starting to comeback and expand.  Part of going with ClarityCap SA capacitors from Rob to get the crossovers in hand and study the existing design beyond photos and documents.  It was a straight forward update vs CSA (i.e. 27uf+1uf, unknown size constraints). Good learning experience plus, out of pure curiosity, I wanted hear what the SE model might have sounded like.  Not too logical from a project perspective though the SE sound has been enjoyable.

Audiogon might have a minimum requirement for sending a PM, so either I missed how it's done or needs to be enabled.  Will send one when that is figured out. It's been many years since being on a forum.

Hi jafant - Here is a post that might be worth reviewing: Beetlemania 2019 Summary

He also posted "Relevant posts begin January or February, 2018. I made my final changes about one year later." (Link)

Should provide some reference to further search.

bas79 - Looks very nice! From the photos, it looks like a production or aftermarket outrigger. Certainly interested in your follow-up regarding the sound.

Intriguing name for paint "Galvanic flat black Painting and spray"

Oxford definition for Galvanic:

1. relating to or involving electric currents produced by chemical action.

2. sudden and dramatic.

Assuming the second is more is the intent 🙂

Searching "Electra Cable Tube Connectors" results in interesting installation and binding post comparison videos. The Gentleman in the videos, who perhaps is the designer, seemed to have thought this through, from ease of installation to showing value with this design, and reasonable price point. Haven’t found measurements (yet) which some would gravitate to alone for sales. Something to further research tonight. Wonder if that design could be tweaked for other uses, i.e. a simplified wire connector with locking mechanisms to add to his patent portfolio.

vair68robert - Adding a few 2.4 images for reference....hope they work and not too obnoxious. 

16 ohm 10w resistor on 2.4 coax crossover:

Mills MRA12 8 ohm purchased for 2.4 upgrade.  Also have the 2, 3, 4 and 30 ohm resistors.

What my production coax crossover looked like before installing SE upgrade kit from Rob G.

Didn't find much more constructive information on the GR Electra tube connectors beyond a few reviews and GR literature.  Ran across a Smiths Connector with "Hyperboloid Contact Technology" that has similarities to the Electra tube. Just had a quick glance and didn't know whether it would be even close to applicable here. Female side was gold plated brass and male side Tellurium copper with crimp. 

Hi jafant, Happy Friday and St. Patrick's Day.  

After a little more digging on the Smith Connector's Hyper Series, there is variety of sizes, metals, termination style (crimp, solder cap, straight) and cost.  For example, 3.5mm socket/pin is ~$50 vs 1mm pin/socket is $5.  

Not suggesting this is better than GK Electra because I don't factually know.  

Links:

Smith Connector Hyper Series

1MM Datasheet

Distributor with pricing

Would put together spreadsheet compiling all the relevant datasheet information and costs if there is interest.

@vair68robert - Actually, your comment made me go back and check how watts and thermals work on resistors.  Appreciate that, and felt it was something I missed.  Thankfully Tom was able to chime in.  Secondly, I did pick up Mundorf 100uf electrolytic capacitors since they were on sale, but was before your suggestion to check the sizes.  There is a noticeable size difference and not sure they will fit properly on the original PCB.  It's likely a throwaway effort if the end result is going film capacitors.   

Didn't have much luck finding a CS2.7 crossover photo just to see the layout and the 1uf capacitors.  I also remember the same folks in this topic mentioning the higher voltage was better.  Someone, and can't remember who, had 2xx volt capacitors and didn't mind them.  Very curious to hear what voltage you go with and ultimately what you think of the Purity capacitors sound .

jafant - You asked earlier about the sound after doing the SE capacitor update.  Instantly, it was clearer and continued to get better since break-in.  T-Bone Burnett, Allison Krauss and Robert Plant's album Raising Sand, track 7 "Trampling Rose" has kicked my system in the backside along the way.  When her voice goes high, I have heard it muddied and seemly off tone.  When switching to Neotech OCC interconnects, it finally cleared up enough at the very top notes and with the SE kit, the vibrato could finally be heard as clear as day.   Since there was a lot of discussion around amps earlier, I am using a Classe CA-2200 with some older Audioquest Midnight II cables.  Cables will be updated either during or after this project.  

Quick update - CS2.4 coax and woofer PCBs now have Mills MRA12 resistors and Mundorf elecrolytics. Not finding newer 28uf and 14uf capacitors and going back to 27uf+1uf and 13uf+1uf not likely to fit well at all. These PCBs may have gone as far as they can go. It is possible to get the SE update from Rob (legacy technology), Mills MRA12 resistors and Mundorf 100uf electrolytics. There is some space between the .15mh/18ga inductor and 28uf capacitor but not likely a good setup.

Not ideal (might redo and lay flat):

Happy Friday @jafant!  

Purchased a PS Audio Perfectwave MK II DAC from an electronics recycler.  Case is in rough shape but does power on.  Arrives Monday or Tuesday.  Not expecting much to work but unless it's complete junk, the plan is to restore and perhaps get a DirectStream upgrade kit if one becomes available.  Headed to Colorado in June and will stop by PS Audio for a tour since those are available again.  

Curious to hear how the Purity cap integration work is going.

vair68robert - Great to hear. Motivates me to replace the 1uf stock coax capacitors. The 250v would fit but not sure about the 800v on these CS2.4 crossovers. Figure that part would be reusable when doing the big crossover upgrade.

(Right now it’s stock PCB, SE kit, Mills Resistors)

Open question to the group, tomthiel and duramax who I believe have been working on a 2.4 crossover design.  Tom, you mentioned point-to-point wiring is suboptimal and looking at a new layout scheme with edge mounting (comment link).  I have been toying with the idea of purchasing a laser engraver for the purpose of creating PCBs and other items to work on with the kid this summer.  In general for all these crossover projects, is Masonite, PCB or another material preferred?  Was edge mounting due to some limitation or was more optimal?

What about modifications to the driver mounting?  Guessing there is a better term, but a gasket for vibration absorption?  Thinner for higher frequency drivers and thicker for lower frequency drivers.  Air tight.  Installation might be tricky (over torqued if an elastic material used) and the design potentially complex.  Might provide some decoupling of the driver.  

Rob - kudos on the update and great info!  Kinda wonder about getting 4x100uf on there.  Wonder if standoffs to another board could have top and bottom mounted 100uf caps. Likely a bad idea with vibration, extending the path, etc...  Think you mentioned PartsConnexion will have PUR in July.  Going to get the 1uf caps for existing coax board and other parts needed for a VTL project.  

duramax747 - are you going outboard with the 2.4s?  I have a feeling that is the route that will be taken but the stubbornness in me wants to explore the internal crossover further.

There have been recent posts sending me down rabbit holes.  Similar to what Rob posted above, it seemed beneficial to create a schematic and studying the crossovers design.  Been toying with an internal 2.4 coax board layout with electrical components on both sides.  Tom Thiel mentioned "signal chaos", point-to-point and two-sided layouts so it seemed worth jogging that path to learn more.  The design considers a short path with input/output separation, component orientation, star ground (simple) and hopefully sufficient thermal management.  

Another rabbit hole was the mechanical and electrical vibration discussion then how to edge mount a two-sided layout.  Since using simulation software is not likely in the cards, perhaps an accelerometer will work.  Not sure how to avoid custom brackets and can print TPU to see how that measures.  TomD mentioned a mechanical approach to vibration but couldn't figure what it was or how it could be modified for this design.    

Those rabbit holes certainly reaffirms previous "it's complex" comments.  Good grief it is and it must have been an exceptional team to create Thiel products for so long.

Think a few of you are on the Facebook page and might reach out there if interested in seeing the layout.  Never fails I post photo watermarked "Do not use, designed by a 5 year old Lego expert" and creates confusion.  Still can't direct message here.