Ok, so how was the reaction to the Tube Tots at this years DECFEST?
Are they likely to be added to the Decware speaker lineup?

Was interested in trying something different with the A/V system.  Had to be bookshelf size.  Followed this thread with great expectations.

Oct. first beat feet to Decfest.  Listened to the Tube Tot's in the main room and the wood shop.  Did not take long to be convinced that Steve has done it again.  The check book came out.

I just might be the first to have a pair in home.  Steve said the 2WPC might not be a good match but in my small (10' x 12') room the SE84 sure sounds great to me.

If anyone has a need for a smaller size speaker these are the real deal.

Dennis

Steve said:  "Ohno Continuous Cast Copper is a whole new game.  Being able to draw a single crystal hundreds of feet long vs. OFC copper that has 100's of crystals per foot is a serious game changer from what I am hearing."

It sounds like this Ohno stuff might be a choice for winding a next generation of output transformers.  Interstage trans too if you decide to build an IT amplifier.

Brian

Go for it!

Show us what you can do!

A most interesting project!

Brian

Tube Tots are making good progress.   Paint next week and then final assembly.



It's really some ambitious cabinet work to create this wave guide shape, otherwise these could be done ages ago.

I hope to have them tested and on the site in January 2022!

Speaking of paint, in what color(s) will the tots be offered?

The Tube Tots will only be available in the figured burl wood / black finish.  There will never be options.

I've been doing a lot of re-visiting the design as I look forward to 30 pair of cabinets to arrive soon...  this is normal last minute second guessing because it's my balls on the line...

Anyway, the Tots are simple... dual 4 inch drivers running full-range with no crossovers.  The jumpers between the top and bottom drivers are gold plated copper rods which have been tested against fancy wiresand are like having only set one of binding posts for both drivers.  That's what you normally want when you use conventional speaker wire.  However, when you bi-wire you need posts for each driver.

Naturally there are other possibilities, such as running a single driver with the second acting like a passive or shorted across a resistor to damp resonance.  Also there is connecting them in series with the positive either starting with the top or the bottom driver depending on how you want to tilt your sound stage.  The tilt comes from a 15 degree phase shift from the voice coils being in series so you can stage one behind the other.  

But tonight I did another round of measurements and certainly there are some issues with running both drivers full range as you get into the top end and in an effort to improve it I got into some Tesla moments with coils.  Started with a .5 mH and measured and unwound it and measured again, and repeated until I got down to .4mH and a lot of things happened.  Putting it on both drivers tilted the response a bit but left it unchanged except we lost almost 2 dB of efficiency.   Putting it on a single driver was a whole different story, and between setting it on the positive side vs. the negative side of the circuit, the negative side measured and sounded best.

So basically we have a small coil of wire replacing the negative jumper on the speakers binding posts.  Below is the standard measurement with both drivers full-range (BLUE TRACE)  vs. adding the coil to the top driver (RED TRACE) .


Click to Enlarge

What is interesting are the results.  Two things happened... the SPL increased by almost 3dB and the imaging is far more focused and the sound stage is noticeably deeper.  It's a great improvement I think, so I will ship the speakers with coils as well as the gold plated rods so you can have either response.

Steve

Is there a recommend stand height relative to ear height at seated position? Thanks

Here is a JAZZ sound demo of the Decware Zen Tube Tots...

https://youtu.be/TAH8bSAc2bo

No longer a concept, will be available soon.

Today I got the Jensen coils with the wax coating for the top driver and it made a noticeable difference over the mismatched combo I used in prior tests.

So we will ship these with both the gold plated rods and a coil for each speaker so that you can configure it's sound to your own liking.

Price is still on target at $1200/pr.

https://youtu.be/RdENMqBRu6Q

Female Vocals

After listening for several weeks now and measuring the Tube Tots with and without the crossover I have decided to add the crossover to the design. The crossover is a single coil placed on one of the drivers to roll it off around 5K.  This improved the frequency response and added nearly 3dB to the sensitivity of the entire speaker so they will now have my blessing for use with our 2.3 watt amplifiers.

I have been evaluating the differences between perfect lay inductors, fancy braided types, and pure copper foil and in this speaker it is critical to use the very best because it has to match a driver that uses nothing and both matching full-range drivers are doing the mid-range and bass.

I ordered the copper foil inductors tonight, so as we do the final inspections on each pair we will also be installing the coils and putting everything back together for a final QC.



click to enlarge

While it does measure considerably better and pick up some efficiency, the sound is far better focused and more relaxed and dimensional with this update. When you listen to both the original design against this latest improvement, the difference isn't subtle.

The first 4 pair of speakers are already here, the rest are on the way by boat. As you may or may not know I am having these custom built by some of my friends in China and the final assembly and testing is being done here at Decware.

And yes we could make them here but I only have two cabinet makers and both are buried with orders so deep they can hardly breath. So when you order some of our speakers on the web site it can take nearly a year to complete your pair while other models may only take a few months. Plus it would cost more and we couldn't make them any better. The specifications on these cabinets are serious. Cabinet walls are 2 inches thick at the front, the baffle is double thick, the noiseless rear port is hugely flared both inside and out and the exotic real wood veneers have A1 finishing, just like we would make them here.  They are like picking up a bowling ball. 

As I have mentioned earlier in this thread, we're going to start things rolling with 30 pairs of inventory and then complete & test each pair as the orders come in. This should drop the wait time to 30 days while we have inventory.

I'm shooting for Feb/March.

Interesting back story behind this update to the Tube Tots...  As you all well know I have been in love with these speakers since I first hear them. They have great bass weight and texture in such a tiny package! Of course the midrange is to die for. They build on my love for full-range crossoverless drivers with the added thrill of even more speed as is only possible from 4 inch drivers. They imaged on the better side of the scale compared to all the competition in the Decware listening room and I just didn't hear anything that was really worth improving.

Then I got the Decware house speakers done and the razor sharp focus and placement they offer was no different than getting an audio firmware update in your head.  After that update I couldn't hear the Tot's quite the same way despite trying for several evenings... it was becoming obvious that something had to be done.

Now with the new reference for focus the Tot's sounded just slightly blurry to me and since they have two drivers running full-range it might be possible to make some changes. Since Tube Tots are so small and the 4 inch drivers are next to each other -- there isn't a real problem with timing like there would be with say a pair of 8 inch drivers spread further apart. It really sounds no different than a single 8 or 10 inch full-range design... but here lies an opportunity because we have dual 4 inch drivers.

Once I measured the speakers and saw the rise in treble response around 7kHz-15Khz I knew that rolling of that second driver just before that rise (around 5K) would probably fix a lot and it did. The frequency balance got better, but that wasn't off enough to be noticeable or even a real problem.  It was the imaging that transformed. The phase angle on these speakers seems to me to be just about more than one could reasonably expect, and the rise in efficiency is a nice surprise.

I am now a really happy Tube Tot guy because they are no longer sounding inferior to the Decware house speakers and frankly the fun sound that they have and the textures... OMG the textures are fabulous... I crave these speakers when they're not in the system.  

So yea, hearing something better than the Tots created a better sounding pair of Tots in less than a week and made it suddenly compatible with our 2.3 watt amplifiers.  Another gift.

I had the speakers made with a mortised circle to receive our logo which was 1/2 mm too small to fit our round speaker logo so I am having some made a little smaller to fit.  When those arrive this coming week I'll be able to take the official product photos and then get started on the web page.

 

One giant step closer!

The first pair of production model Tube Tots have been completed.  Now we can start working on the web page and then we'll begin to take orders.











Steve

It's a Beauty!

Brian

$1149/PR

Owner's Manual:  https://www.decware.com/newsite/TubeTotmanual.pdf

Drew T. not yet. Steve will put on the product list when they get the page info set up. Check his post w/ picture above.

HK

Steve:  very interested in the tots.  I also very much appreciate how you post measurements.  I’m not a speaker designer (strong understatement).  I’m curious about the dip in the brilliance region in terms of cause (curiosity) and how it influences the tot’s’ character?  Any interest in sharing your thoughts?  How do the measurements and sound stack up to your new 945 (am I getting that number right) prototype?

I thank You so much for that explanation! I have never understood anything about Phase.

Brian

How tall do the stands need to be? Buying the speakers and want to be sure stands are available when they arrive. (Buying as soon as they can be ordered)

Hello, trombonium.
Welcome to the forum.

Brian

Appears the tots are on the speakers page.  4th from the top. And the webpage for the tots is active. And with the new website theme, no less.

https://www.decwareproducts.com/zentubetots

I have a pair of Tube Tots for about four months now.

I use them with a SE84C+ or an older Taboo for a A/V setup..  The room is small..

I have absolutely no plans to replace them.  Even for movies I find no need for a sub.

Well worth the investment

The holes are for large black knobs that have yet to arrive.

OK, So let's talk about stands...

My first experience with the horrifying effect of ruining the sound of a speaker with a stand came in the early 1990's with a pair of PSB Alpha bookshelf speakers that I had on some weird triangular columns that I stood up on a board and set the Alphas on top of.  These hollow columns were part of some retail display from a store that I scarfed up along the way.  Setting them on a flat board floating on the carpet decoupled from the floor and the speakers directly coupled to the top of the hollow triangular columns -- the sound was glorious.  I enjoyed it for many months, but the stands were easily tipped. They were a balancing act and even my cat could launch one into the wall.

So one day I grew a pair and purchased some hi-end steel stands that I filled with lead shot and spiked to the floor and spiked to the speakers...

Yea, that was probably it right there.  

Anyway, I turned on the stereo and the magic sound I had grown to love was completely gone.   I had this hatefully dry, etched, tipped up sound that had almost no bass and no imaging. I was so stunned I didn't know how to process it frankly.

The stands were quickly donated to friends that weren't really friends.

Fast forward 30+ years to today and in wanting to see how these things looked before the rest of the parts arrived, I had to use make shift spikes and cones to see what the final look would be close to.

I had the stands firmly spiked to floor through the carpet, and the speaker spikes installed resting in magnesium disks that were hard coupled to the top of the stand - a way to get coupling without scratching the wood.

I turned it on and the magic sound of Tube Tots was completely COMPLETELY C O M P L E T E L Y gone.

The sound stage went from 16 feet wide to 5 feet at best.  The highs were shot.  The midrange was totally f'cked.  Bass was well I don't really know because I was so distracted by everything else that was broken.

See, these speakers are presently set on the inside of the 3-way house speakers so they are only 5 feet apart.  Despite this odd placement, they have a sound stage that is literally 16 feet wide.  It sounds like the speakers are placed well outside the 3-ways.  Suddenly spiking the speaker to the stand which is spiked to the floor which is concrete slab on dirt... made them sound like a boom box with a sound stage that was 5 feet wide.

I'm not kidding.

So the solution to get the sound back is to remove the spikes from the bottom of the Tube Tots and set the speakers on rubber 0-rings with the following specs:  Hardness 70 SHORE A (NBR 70) AS568 (#-210) 1/8x3/4

See picture:



This TINY little change restored the full glory of the Tube Tot sound and image and stage.  Literally.  The original stands that cost $60 on Amazon made from glass and thin aluminum were in fact perfect as well because they had shallow rubber pads between the speaker and the stand. These are at least as good if not better in sound but several notches better in looks I hope.  I can already hear the way they punch music into the room has gotten better.  Immediacy.

Steve