Dual Lambda TD12S & John’s passives radiators in my subs

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    mfishmike on #274

    It’s good to see John is back up and running! 8)

    He has asked me to post some build pics of my system using his Lambdas. I can’t compete with the studio monitor post and the awesome wooodwork that John did, but we are very happy with what we have. 😀 I’ve also posted pics of his new 12 spoke passive radiators which will become his standard production. I’ve loaded the 1050 gram PRs to 1800 grams for the subs.

    These are the TD12S with phase plugs crossed at about 750hz with the dual Scan Speaks picking up the midrange work and the Hi Vi Research RTII isodynamic planer tweeter. Running the 2 Lambdas in each main and the Scan Speak mids in parallel, this gives me a 6 db gain in overall output and the performance is absolutely outstanding with two channel music or full surround. I’ve also enclosed a picture of the crossover I built, using the design that John worked up for me. No one who has ever been here to audition my system has heard any better audio in a home. I whipped out my db meter last night during Eric Clapton’s Crossroads concert and was pegging 115 db with more headroom to go. Very clean and undistorted.

    I have built a second sub identical to the one in the bottom picture and have them stacked, working as a single subwoofer. They are corner loaded for room gain. I will be replacing my Parts Express passive radiators with John’s 15″ 1050 gram passives in the subs. At 1800 grams, the new passives should bring my tuning frequency in each of my subs from 25.5 hz down to 20 hz, (on paper). I should see a bit even lower response than the modeled tuning frequency due to the softer suspension in John’s PR’s. At full cone excursion, I will see a response just below 13hz. I sure would have bought them from John if they were available from him when I needed them! All 9 grill frames are at the upholstery shop for new black audio grill cloth replacement.

    I’ve already started rebuilding the mains again. I’ve had the numbers run with WinISD on the lower Lambda section with the ports, and I’m currently tuned at 30.04 hz., which is higher than what I thought I had. I have cut the new passive radiator holes in one of the mains and will be putting PE passives in, replacing the ports. I think I may have had some port resonance, and according to Vance Dickason’s Cookbook, “an improperly placed port could multiply resonances by as much as 10 times”, so it was a no brainer to eliminate them and use the PE passives I already had with John’s new ones on the way. Mike P.’s WinISD models out the Lambda section to 23.8 hz. at 6 cubes and dual TD12s with the 4-1100 gram PE radiators. I’m also going to have to rebuild and re-laminate the baffel for the Lambdas because the patch job where the flared ports were installed will look very undesirable.

    This is why I DIY. I enjoy constantly upgrading my system.

    Please check out my last post showing the new install of the mains with the ports removed and the new 1080P Mitsubishi setup. The center speaker is now under the TV, tilted up to the listening area.

    Cudos to John Janowitz and Mike P. for all of their help. :mrgreen:

    mfishmike on #3435

    John’s new 1050 gram 15″ passives arrived today with excellent packaging and the build quality is fantastic.
    Here are a couple of photos of his new 12 spoke passives that will become his standard. He is out of the 4 spoke baskets now and the parameters will continue to be the same. In the foreground of the pics you can see the 750 grams of washers I’ve epoxied in 4 of the passives. I’ll post the results when the subs and mains are finished.

    mfishmike on #3436

    Moving the Parts Express passives from the subs to the mains now.

    John’s new 1050 passives are in the subwoofers now loaded to 1800 grams and tests result in a nice drop to 20 hz. The tuning from 25 hz to 20 hz makes the world of difference. They are deeper, richer, and tight. You don’t notice the sharper roll off expected in a passive radiator subwoofer when the tuning is at 20 hz. I’m about done with one of the mains and hope to have both finished by the end of Memorial day.

    One of my customers gave me a pair of Bang & Olufsen speakers which are so incredibly clean and crisp. I’m using them for my mains during the rebuild. The quality is oustanding! They are made in Denmark. I had some left over drivers I was going to use to build some great surrounds and wire them in parallel my in ceiling Polks for better the surround sound, but now I’m going to disconnect the Polks and mount these B & O tri-directional speakers at the ceiling & wall over the crown moulding area pointed at the seating area for my surrounds. They are rated 96 dB @ 2 watts. My customer is very wealthy and was going to donate them to Goodwill and asked if I wanted them. I told her I knew B & O’s reputation and could really use them. She said they were very expensive in 1986. These speakers were placed in the Museum of Fine Arts due to their innovation and design. You can see one of them on the vintage Kenwood speaker. I found out the ABR or auxillary bass radiator (passive radiator) steel plate had their foam surrounds rotted and were loose in the cabinet but I redesigned them and have them posted on my new website http://www.speakerhobby.com with rebuild and installation photos. This was a manufacturer’s flaw in design and several people who own these Redline 60’s that are broken and are using my modifications to repair their own speakers. The factory no longer sells the ABR replacements.

    mfishmike on #3437

    I think because John has asked me to post my speakers with the Lambda drivers in them, it would be appropriate to show those of you who have never seen a good picture of this Lambda driver some some photos of them while I’ve got ’em out and making the upgrade to the mains.

    I purchased these drivers from John in late 2004 or early 2005. I’ve got a powerful, high current Rotel receiver/amp and listen to most of my music in two channel stereo and drive my mains pretty hard when the wife is gone. I’ve been doing this since I purchased and installed them from John 3 years ago. They still sound as good as they did when I got them from him.

    The Lambda speakers are sought out and shipped worldwide to audiophiles seeking the finest drivers they can get their hands on. Overseas shipping is very expensive but the cost is not an issue for these folks because of the Lambda’s reputation. I was lucky enough to purchase these 4 from John when he was a distributor for Nick McKinney, the owner of the Lambda line at that time. John has since bought the company and is now producing the same drivers and has several models for you to choose from, keeping the traditional Lambda specs with his drivers. You will see the Stryke label John put on the drivers in the photos. This is the name of John’s previous company and these are the original Lambda 12TDs drivers.

    If you purchase one or more of his Lambda drivers, you will continue to be as excited to hear them as I am; every time I turn on my system! 😀

    mfishmike on #3438

    In these photos, the finished mains are in transit from the shop to the house. They wanted to stop in the driveway and asked for some photos to be taken with the natural sunlight. The third photo shows the new grill cover frames I made to cover the new passive radiators on the sides of the mains. They will just snap in with the fasteners I’ve used. Now I have 13 grills and after 10 years of rebuilds and new speakers projects, my upholstery shops have changed colors a little, so I purchased a large quantity of black audio grill cloth and am having all of them completely redone with the same cloth, at the same time for a very nice finished look to my system. Just looking at the finished mains, one wouldn’t think that there are literally months and months of labor, design, redesign, and lots of money to finally have a superior quality sounding main speaker. I get a kick out of going to both the average retail and the “high end” audio stores and listening to their speakers for sale, and then relaxing in my living room appreciating the fruits of my labors and research. The high end audio salesmen call my mains, “refrigerator speakers” to taunt me. I don’t mind at all because my “refrigerator” sounds so much better than theirs!

    Nasty N8 on #3439

    Nice stuff nice to see some other big main speaker designs. I am working with John on my surround system design I will be using 2 TH 12s drivers in each speaker a single 6.5″ pro mid and Fountec NeoPro5i ribbon. I am going to try and do this for all 5 speakers but may slim the rears to single TD10s a mid and ribbon. I really need more width to my room at 11.5′ wide with a 9′ screen kinda limits the space for big speakers. May try and get them behind the screen but that puts them up high (about 42″ tweeter height) again space issues.


    mfishmike on #3440


    John’s the man….period….He knows his suff….If you visit my website and look at my “Mains” page, you can see what he did for me.

    I think going the 10″ for your rears, if you are talking about your center back speakers that ought to perfect as they don’t need to be as big. I’m running a couple of small B & W DM 303’s paralled with a pair of Cambridge 8″ separates for the low end with the receiver crossoved over at 60 hZ to the sub, and that’s all I need.

    You will also be pleased with the Fountec ribbons. I’ve got a pair of the JP2’s left over because I blew them during “Armageddon” because the crossover slope wasn’t enough. I should have used a fourth order xover for the ribbons. Make sure you’ve got that area covered in your xover design. I had Madisound rebuild them and they are in a box waiting on a new project. They are sweet sounding tweets.

    Yes, the available room can hurt. I built my own home and built my living room about 18 x 24 so I could have all of the room I needed and prewired with #14 gauge wiring. You may loose some highs if they are hidden behind the screen, depending on the material…..I’d scratch out a schetch and email it to John for his advice.

    Big speakers produce big sounds and can be wife and company freindly, but not neighbor freindly. I’ve dropped my Lambda sections’ tuning frequency to 23hz now with the 4 new passives I added to each main and couldn’t have done that without the big box. Bill Dudleston with Legacy Audio has designed the Whispers and his Helix which are absolute monsters, weighing in at several hundred pounds. They probably stand about 6′ tall. You can get the Helix for about $40,000 the last time I checked, 3 years ago. He wouldn’t have designed the large speakers if you could get really high end sound out of smaller ones, even though he sells smaller ones.. I think the Whispers have 5 – 15″ drivers in them and are close to $20k. It’s all about what you expect out of your system.

    I demand front row tickets when I sit down to a music dvd concert or movie!

    Have fun,

    mfishmike on #3441

    I finally have the rebuilt speakers in place now along with a new 65″ Mitsubishi 1080P DLP with the center speaker mounted with a slight tilt upwards towards the listening area. Adding the four passive radiators to each main and removing the ports has reduced the box tuning to 23.8 hz from 30 hz and without the ports, I’m not hearing any more resonance.

    I hope I’m through building, re-building, and spending for a while. I think I have it as good as it gets for the average home now, thanks to John.

    UPDATE ON JULY 29, 08~~~~~~~~~~~~~~~

    I held an audition of my system using the Lambda drivers and Johns passives in my system and here is a post from one of the members of the Houston DIY group who attended the audition:

    “The sound and clarity of Mike’s set up was amazing. Dynamic and powerful. The visual impression looking at the array of speakers was awesome enough; the impact of his creation was truly impressive. As much as I was in awe of the sub’s – the center speaker was the star in my opinion. Listening to the demo disks displayed a whisper as clean and clear as branches breaking and even explosions; there was never a need to struggle to make out any sounds. The sub’s fill the room in a wave that’s felt before heard – not something that I’ve experienced in theaters, not to that extent!

    I was excited to see the system in person, but more excited after I left. Truly a successful DIY experience and it was great to hear what’s possible “away from retail.”

    My 2c…

    Oh, thx for all the grub. Truly a gracious host!”

    I attribute to Tony’s post about the quality of the impact of the subs to John’s new passive radiators. The passive radiator design is so clean and low!

    mfishmike on #3442

    My Rotel 1065 was giving me some decoding switching problems so I bought the Next Generation NAD T-785 AVR with a rating of 120 wpc x 7 channel, full disclosure watts and wow, what a difference in home theater movie experience I’m getting now. The NAD has it right with their decoding and 4 new boards that are coming out in January for further enhancements to this unit. The downside is the NAD’s output is less than the 100 wpc that the Rotel had. What a let down! I did some hard searching and found a practically new Rotel RMB 1095 200 watt x 5 channel amp and boy, what a soundstage I have in my living room now! I’m just using the NAD for my processor for the HT and am using its amplifier only to power the center backs. I’m able to take advantage of those wonderful Lambda midwoofers’ output capabilities now with all of this horsepower and it really puts you on stage with the band or in the movie! I have been using these Lambdas since 2004 and really drive them hard. They are certainly well built and high quality. Your dollars are well spent when purchasing these babes.


    mfishmike on #3443

    My upholstery man had a heart attack and bypass leaving me the task of recovering my own speakers. There are 13 grills and I’ve never done any upholstery work. I started on Christmas day and finished the work and installation on Sunday. I’m sure I saved a lot of money because this was a huge job! The air staple gun for upholstery work and staples were under $100 bucks. John’s Lambda woofers and passive radiators are still doing me a fantastic job. Here are some pics of the new grills:

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