Betsy OB MTM project

[Randy in Caintuck]

I was really happy when the announcement was made that the Betsy drivers were back in stock and my order showed up on Saturday morning .....

It allowed me to finish a little project that had been bouncing around in my head for a while. I am a big fan of MTM speakers and have owned (or currently own) several different speakers with this driver configuration. They all sound very good to my ears and I wanted to give the Betsy drivers a spin in an MTM baffle. I used a Fountek ribbon driver for the tweeter crossed over in "super tweeter" territory and the project has turned out very well. I am still playing around with the crossover point for the ribbons and the Betsy drivers will only get better with time as they break in, but the sound is everything I hoped for at this point .....

An externally hosted image should be here but it was not working when we last tested it.

Larger photo here.

Here is a photo of the Betsy MTM OBs sitting next to my current reference speakers which use Visaton B200 and Heil AMT drivers .....

An externally hosted image should be here but it was not working when we last tested it.

Larger photo here.

The 15" drivers on the big baffles are Hawthorne Audio Augies driven by a pair of plate amps and I have the system wired so that the Augies can be used with any main speakers in the system.

The Betsy baffles and the Visaton baffles sound a lot different, but both sound very good ..... and the little bit of money I have in the Betsy baffles makes me like them a lot.

Thanks to Paul for a very nice driver at a price many music lovers can afford.

My guess is that after a few of my audio buddies hear my new speakers Wild Burro Audio will be making a few additional sales .....

Best wishes,

Randy

 

[GM]

Very nice, especially the electronics!

GM

 

[cervelorider]

Awesome!

 

[Randy in Caintuck]

Very nice, especially the electronics!

GM

Howdy GM,

Thanks for the kind words .....

The front end stuff is a CEC TL-2 top loading belt drive CD transport and a Camelot Uther DAC with the current Anagram mods and upgrades + an Onyx (Music Hall) player used as a transport for a few "burned" CDs that the CEC won't read.

The amplifiers are an interesting lot ..... a Decware SE84C+, a custom built "Type 10" amplifier from Greenvalve Audio that uses thoriated filament power tubes and a mercury vapor rectifier, a 300B amp that started out life as a stock unit from CGV Electronics and was later modified by Dave at Parker Audio ..... and finally, a prototype 6CA7 pentode amp on temporary loan from a new company, La Dolce Audio.

Happy listening,

Randy

My Website

 

[Randy in Caintuck]

Awesome!

Thanks cervelorider,

I was thinking the same thing about your Betsy Cello speaker .....

From what I understand, we may get a chance to meet next week at the home of an audio buddy we have in common in Columbus, Ohio.

I hope that works out, it would be great to meet you in person .....

Best wishes,

Randy

My Website

 

[GM]

Greets!

Sadly, I only recognize the Decware name and 300Bs always get my undivided attention, but no clue what the others might sound like. I'm curious what advantage this CD player has over the usual tweaked/relatively high end tray designs though.

GM

 

[tubo]

Very nice setup you got..

How did you setup the augies? Parallel augies driven by a plate amp? What frequency do they come in?

Im also contemplating on an mtm. It will be setup as augies , silver iris, isophon ph2132e coax, silver iris, augies. Iris will be low pass between 200 to 400hz then isophon will take over from there. Im wondering how the augies sound mounted high on the baffles..

Thanks for your input

 

[Randy in Caintuck]

Greets!

Sadly, I only recognize the Decware name and 300Bs always get my undivided attention, but no clue what the others might sound like. I'm curious what advantage this CD player has over the usual tweaked/relatively high end tray designs though.

GM

Hi GM,

As to the CEC transport, it's hard to put an accurate description on exactly what it is doing that I like so much ..... but I have a couple of other friends who also own these transports and all of us agree that there is an "ease" to the sound that we don't hear with other transports that we have tried in our audio rigs. I have tried a lot of transports with my DAC over the years and the CEC seems to give the music a different sense of timing than the others.

I'm not sure how much of it has to do with the top loading and how much has to do with the belt drive. A lot of "reviewers" over the years (which I put very little if any value in) have said that the CEC transports have a more "analog" sound than other transports. Who knows ..... The fact that there is a heavy puck that sits on top of the CD might also have an effect on the sound.
Years ago on the old Decware forum, I had a running "friendly discussion" with some die hard vinyl fans who stated that I was either deaf or stupid or both to think that digital sound could ever be pleasant and musical. After buying a CEC transport for his system, one of the gents made a public apology on the forum and said that I wasn't quite as deaf and stupid as he had originally thought .....

Best wishes,

Randy

 

[Randy in Caintuck]

Very nice setup you got..

How did you setup the augies? Parallel augies driven by a plate amp? What frequency do they come in?

Im also contemplating on an mtm. It will be setup as augies , silver iris, isophon ph2132e coax, silver iris, augies. Iris will be low pass between 200 to 400hz then isophon will take over from there. Im wondering how the augies sound mounted high on the baffles..

Thanks for your input

Hi tubo,

There are two plate amps, one for each channel, driving the Augies which are wired in parallel, giving the amps a 4 ohm load. The plate amps are driven from the speaker taps of the main amplifier into the "speaker level" inputs.

We had an interesting discussion on the Hawthorne forum a while back about running the Augies with two plate amps "in stereo". A lot of folks are of the opinion that there is no benefit to a setup like this and that it is better to just "sum" the left and right channels to the Augies.

I have tried it both ways and feel that the "stereo" setup sounds better. To me, placement of bass instruments in the sound stage is better and I get a better sense of the space where the recording took place (if the recording allows for it).

In my room, the Visatron drivers (and the Betsy drivers) go down a bit lower than they do on paper ..... and I have the crossover at around 70 hZ on the plate amps. The frequency response may just be an anomaly of my room ..... I'm not sure, but the bass integration sounds good to me.

The high and low Augie setup loads bass into the room very well. At one time, I had the Augies on smaller, separate baffles.

They sounded good, but I like this setup better. It is smoother, possibly because the upper Augie is interacting with the ceiling.

I also believe that the current setup (WMTMW) expands on the MTM concept and gives the effect of "one large driver" over the entire frequency range. The individual drivers do not call attention to themselves and the speakers "disappear" amazingly well for as big as they are .....

Best wishes,

Randy

 

[tubo]

RANDY,

THANKS VERY MUCH FOR THE RESPONSE. EXACTLY WHAT I WAS THINKING. ILL JUST GO WITH 2 BAFFLES ON EACH SIDE. IM STILL WAITING FOR MY ISOPHON PH2132E TO BE DELIVERED.

THANK YOU

 

[GM]

A lot of "reviewers" over the years (which I put very little if any value in) have said that the CEC transports have a more "analog" sound than other transports. Who knows ..... The fact that there is a heavy puck that sits on top of the CD might also have an effect on the sound.

Well, with belt drive I can believe that since wow/flutter will tend to be much higher than direct drive and disc clamps do wonders for vinyls, though can't think of a reason why it would affect a CD unless air currents inside a tray system can cause jitter, but then don't they have some sort of correction built in?

Anyway, it would be interesting to compare it to my damped Elite PD65 that I A-B'd with a contemporary Meridian and Mark Levinson, both of which had less bass gain BW, consequently sounding 'light', 'airy' up top, but not nearly as 'rich' sounding like vinyl tends to be.

GM

 

[Randy in Caintuck]

Anyway, it would be interesting to compare it to my damped Elite PD65 that I A-B'd with a contemporary Meridian and Mark Levinson, both of which had less bass gain BW, consequently sounding 'light', 'airy' up top, but not nearly as 'rich' sounding like vinyl tends to be.

GM

From what I understand, the Elite PD65 uses the "Stable Platter" transport mechanism. A few years ago, I owned a Camelot Morgana CD player that used the same mechanism. Camelot offered two models, one was a dedicated transport (I forget the name) and the Morgana which had a built in DAC.

I really liked this player and also used it for a while as a transport. I'm sure that your Elite PD65 is a fine sounding player. I have never heard one, but have heard some very positive comments about it.

Randy

 

[tubo]

Randy,

how did you wire the betsy mtm? what is their impedance and and what tap on your amps are you using?


thank you

 

[Randy in Caintuck]

Randy,

how did you wire the betsy mtm? what is their impedance and and what tap on your amps are you using?


thank you

Hi tubo,

Sorry that I didn't get back to you right away ..... I was visiting an audio buddy out of town and just now got a chance to check the forum.

The Betsy drivers are wired in parallel. They are 5.9 ohms each according to the website, so the two in parallel would be 2.95 ohms. I run them off of the 4 ohm taps of my amplifier. With just a single cap on the ribbon, the load is pretty friendly and my amp drives them with no problem.

I must tell you though, the MTM project did not work out as well as I had expected. I have another pair of speakers using Visaton B200 drivers in an MTM configuration and I like them a lot ..... but, the Betsys not so much. I took the speakers with me to my buddy's house yesterday and he and I as well as another visiting friend much preferred the single Betsy + the ribbon.

The Betsy MTM setup certainly had more dynamics and upper bass, but was not as smooth, coherent or musical as the single Betsy and ribbon. We tried them with several different amplifiers and the result was the same each time.

Oh well, live and learn ..... the good news is that I have a spare pair of Betsy drivers to experiment with .....

Best wishes,

Randy

 

[tubo]

thank you Randy,

Im hoping that my next speaker project will be successful. im still busy with other stuff but hopefully can start on it in a month or two. Im thinking of copying your design but will incorporate a pair of Hawthorne 15 silver iris for midbass duties and an isophon ph2132e coaxial for mid and highs, a couple of 15 augies per side, one on the very top and one on the bottom.

By the way completely out of topic, how does your greenvalve 10y amp compare to Terry's 6ca7 amp? i am very interested with Terry's amp.



thank you

 

[Randy in Caintuck]

By the way completely out of topic, how does your greenvalve 10y amp compare to Terry's 6ca7 amp? i am very interested with Terry's amp.

thank you

Hi tubo,

Interesting question ..... and very hard to answer fully. About the only thing that these amplifiers have in common are that they use vacuum tubes .....

The Greenvalve amplifier is a "one off" custom DH-SET amp that Buzz built for me. It is very low powered, but deceptively powerful sounding because of the design of the power supply and the serious iron used in the design. It images in a way that is different than any other amplifier that I have ever heard ..... very intimate and realistic, especially with the simple, acoustic music and vocal fare that makes up the majority of my music collection.

Terry's 6CA7 amplifier, being a pentode design, has an amazing "jump factor". It is also very real sounding, but in a different way. It has some of the best "toe tapping" effect that I have ever experienced. It is hard to sit still while listening to music through this amplifier and I often find myself "dancing in my seat" while the music is playing with this amp ..... not a pretty sight, for sure

I think that you would be impressed with the 6CA7 amp. It will play a lot louder than the few watts would indicate and has amazing dynamics. The one I have on loan has some switches that insert and remove different amounts of local and global feedback which give the amplifier multiple "personalities". This can be very useful, and of the several people who have heard the amp in my system, almost each one had a different preference for which combination of switches they thought sounded best.

Randy