[-Richard-]

I visited Roger Modjeski's house/laboratory on Monday...

I brought down my Silver Iris Coaxial's in my Open Baffles and Roger hooked
them up to his new revolutionary RM 245.1 Single Ended Triode amplifier...

Srajan wrote a nice introduction and overview of this amazing amp on 6 moons:

http://www.6moons.com/industryfeatures/ram/ram.html

Roger, being forever the curious and intrepid scientist that he is, did not hesitate
to measure the SI's responses while we played them...conclusion?

Roger was impressed...The Silver Iris Coaxial's really are measurably 96db
sensitive! Also he was very impressed with their reasonably flat response...
he admitted that he has not seen many drivers that were that consistent
across the spectrum...a further confirmation of what I have been hearing...

The bass response of the SI's was at least comparable to Roger's own
sub-woofer which he uses to flesh out his reference electrostatic speakers
which he designed himself...more about Roger's electrostatic's later...

We listened to music for a few hours swapping 45 tubes...from New Old Stock
45's that go back to the early 1930's to the new aristocratic KR tubes,
to the wondrous king of the new tubes, the Emission Labs Mesh Plate 45's...
Roger is the dealer for the new Emission Labs and KR tubes under the
Ram Tube division of his company...

All the while we watched what we were hearing on his oscilloscope...which among
other things allowed us to see how many actual watts were being used to generate
the powerfully penetrating sound levels that we were listened to...less than 1 watt!!!!!

I left with Roger's 245.1 and several tubes to explore further with my SIC OB's at
home...my listening impressions then are based on what Deb and I are hearing
at home over the last 5 days...

First a quick look at Roger's new amp...This is the most elegant design I have
ever seen for any SET 45 amp (take a look at the pictures in the above link)...
Notice there are no transformers in sight! Roger hand-winds his own transformers
in his laboratory and he has found a way to circumvent the heavier-the-metal-the-
better-the-sound misconception...heavy transformers absorb and trap current
which results in power loss and distortion on already low powered SET's...
as Roger says: "Power Is Precious"...the transformers are placed inside the case...
which Roger designed to reflect his love for the Classic Black Steinway pianos
which he played when he was the head recording technician for live performances
while he was still a student at the University of Virginia...an overlapping black
Bakelite-looking material on top and bottom sandwiches a beautifully hand-rubbed
Walnut wood finish...this amp simply reeks with class!!!!!!

The top front of Roger's 245.1 SET begins with a Feedback Knob that begins at
ABSOLUTE ZERO FEEDBACK...the feedback loop is entirely disconnected in
the zero position...then feedback can be dialed in 3db increments to 15db's of
feedback for anyone interested in experimenting with feedback options...
behind the feedback dial there are 3 small LED water clear plastic lenses...
when the amp is turned on the center lens, which Roger calls the Pilot Light, glows
red...the other 2 LED lenses which are positioned on the same horizontal line
as the Pilot Light are each in front of the two 45 output tubes...

You use these 2 LED lenses to control biasing...and it couldn't be simpler...
in the back of the amp, but easily accessible, are 2 thin knobs that you turn to
introduce or take away biasing voltage from the tubes...the lenses are tightly focused
making it easy to judge the brightness-matching to the Pilot Light LED lens...
you simply dial the biasing in until both lenses glow like the center Pilot Light...
the subtle nuanced control of the red glowing light is remarkable and it really works...
what I wound up doing is to dial in more negative bias which lowers the idling
current in the 45 and will add years to the life of any 45 tubes I am using!!!

While most 45 amps are cathode biased, Roger uses an adjustable negative grid
voltage thus avoiding the power-wasting, chassis-heating cathode resistor that
usually consumes 20% of the power supply energy and converts it into heat in
the chassis. The amp runs amazingly cool to the touch and Roger notes that
reducing the interior temperature by just 15 degrees doubles the life of
the capacitors...Roger promises to share more details of his revolutionary
design when he writes the amplifier notes that will go on his website...

There are also 2 "Humpot" knobs in the same back area that you use to dial out
any hum that might appear because of variations in tubes...just as easy to use as
the biasing knobs...you dial each knob until any residual hum disappears...

The feel of this amp is like an exquisite musical instrument that allows you to fine
tune all of the fundamental variables that everyone is concerned about when they
enter the world of SET amplification: Feedback, biasing and hum control...
in the most simple and elegantly functional easy-to-use controls...

The sound of Roger's 245.1 SET 45 tube amp playing Darrel's Silver Iris Coaxial's
is pure magic...it is all about TONE, TONE, TONE...this combination projects the
richest harmonic presentation I have ever heard...voices are palpable, intimate
and richly textured...instruments sing with their natural timbre intact...
The all-over effect is tremendous space and a sonic penetration that must be
heard to be believed...more real than real!!! Meaning that this combination makes
an instant connection to your emotional fibers...goose bumps appear all over your
body...you melt into the music's inner liquidity...

I am referring to Roger Modjeski's new 245.1 SET 45 tube amp as revolutionary...
that is because Roger doubles the power output of the 45 tube to a full 4 watts...
not the 2 watts, and in many cases far less than 2 watts, that every other 45 amp
is only able to achieve...and Roger achieves this doubling of power without any
stress on the tube...it is a matter of circuitry design...Roger went back to the
RCA Radiotrone manuals published in1922 with the title "Radio Enters The Home,"
and studied the original schematics that every SET tube amplifier is based on...
the result of his years of study and experimentation is the RM 245.1 SET amplifier
with its doubling of the power of the 45 tube...

So what does 4 watts sound like on the Silver Iris Coaxials? Well...we never
measured more than 1 watt at voluptuous sound levels...which is a tremendous
achievement of both the SIC's and the RM 245.1 amp...

I made a brief earlier reference to Roger's own electrostatic reference speakers
which he designed himself...Roger A/B'd them with the SIC's for comparison...
Roger's electrostatics achieves noticeably higher frequency levels with more
HF detail, transparency and resolution...however the SIC's have that midrange
magic and low frequency extension that I find so addictive...I thought the SIC's
sounded more organic in our all too brief listening session...however each speaker
does very magical things in their own right...

I was brought up listening to recorded music on British speakers from the age of 10...
the British tune their speakers for the voice...for all their apparent reserve they
love the opera and every other musical form that serves the intimacy and rich
presentation of the voice...Darrel's Silver Iris Coaxial's have that in common with
British speakers...but unlike British speakers, the Silver Iris Coaxials refuse to
act well behaved...at least in terms of the emotional side of their nature...
emotion simply pours out of them...and this is were the RM 245.1 joins them in
perfect synergy...

The RM 245.1 SET amplifier brings out the potential emotion of the SIC's with
extraordinary detail, a super rich harmonic palette of sonic colors, ultra-
saturated instrumental timbre and textures...and that incredible spatial 3-D
presentation that is supported by the Open Baffle paradigm...

Roger sells the RM 245.1 for $1850.00 which includes the driver tubes...and Roger
has a selection of output tubes starting at $150 for the pair, hand tested, selected for
low noise and matched for gain....so for less than the price of some kit amplifiers you
get a 45 amp THAT DOUBLES THE POWER OF THE 45 TUBE...TO 4 GIGANTIC
WATTS...INCREDIBLE CONTROL THAT IS FUNCTIONALLY ELEGANT...
AND A BEAUTIFUL ALL-OVER DESIGN...Deb loves it!!!! Deb is a designer,
so the classy design of the amp is an important consideration for her...

I am the first person to purchase Roger's RM 245.1 SET 45 tube amplifier...
and I am thrilled with it...Deb is thrilled with it...and in combination with
Darrel Hawthorne's Silver Iris Coaxial’s, it creates a sumptuous, throbbing,
emotionally potent musical presentation...

What it is then that the RM 245.1 does that I have never heard before...from any amp...
is that it puts an inner light into the music...an inner fire erupts that sets the music
on fire...it is a dynamic energy that persists and infuses itself into the voice
and every instrument that is played...and it works it’s magic with every
type of music we play...

Roger has thrown down the gauntlet and pushed the potential for the Single Ended
Triode revolution to a new level of power, elegance and rich harmonic presentation...
And Darrel has done the same with his Open Baffle driver design. Together they
put the thrill back into listening to music...and justifies my years of searching for
the magic I knew was potentially there, but up until now only dreamed about...

You owe it to yourselves to purchase Roger's exquisite new powerful RM 245.1 SET
amp and Darrel's Single Iris Coaxial's and join the revolution in audio!!!!

Thanks Roger, thanks Darrel...this is really fun!!!!!!!!!

Warm Regards -Richard-

[JLM]

So how do the Silver Iris compare to the B200 in your opinion?

I've not heard the B200's, but an afternoon with fresh Silver Iris drivers showed them of low resolution.  Perhaps further break-in would help.

[-Richard-]

The B200's begin to lose Low Frequency information at around 200 Hz...

There is LF information being produced, but it has only a very subtle presence...
so the B200's need bass augmentation in order to properly flesh out a convincing
sonic picture...

Darrel Hawthorne will be presenting just such a Bass Augmentor Open Baffle Driver
within the next week or so that goes down to 20Hz...when the B200's and Darrel's
Silver Iris bass augmentor have a chance to work together, I suspect there will
be real magic there...I ordered a pair so I should have something to report when
they arrive and I have had a chance to impliment them properly...

I have no idea what you could possibly mean by the statement "lack resolution"...

Many audio hobbyists have grown accustomed to hyperdetailed information...

I listen to a great deal of live performances that are unamplified...so my reference
for RESOLUTION, IS REAL INSTRUMENTS CREATING REAL MUSIC
IN REAL SPACES...

If that level of resolution is met, I then place my attention on whether or not there
is a palpable magic attending the musical "event"...by magic I simply mean the
inner energy of the music...its life force...the way it penitrates the space of my
listening room...its harmonic richness...

What I am hearing with the combination of Roger Modjeski's RM 245.1 SET
45 tube amp and Darrel Hawthorne's Silver Iris Coaxial drivers implemented in
Open Baffle configuration is pure magic...everyone who has stopped by my
home for a listen is just as affected by what they hear...

Admittedly, the Silver Iris drivers change their sonic characteristics considerably
as they burn-in...the first impression is one of astounding space...comparable
to huge horn speakers costing dollar amounts equal to expensive classy cars...
then one hears the tweeter...this is a coaxial driver...in a somewhat spotlighted
fashion...after about 30 hours of burn-in things begin to coalesce...a wonderful
merging of the tweeter and mid/woofer occurs that produces a fully convincing
organic sonic presentation that is deeply satisfying...

You may have heard the drivers during that all too early phase of its burn-in as
you suggest...

But the SIC drivers are not hyperdetailed...I do not hear any detail that does not
serve the music in some intrinsic way...what I hear is a SUPER CHARGED
MUSICAL ENERGY SATURATED WITH TONAL TEXTURES AND A
RICH COLOR PALLET...but I am driving the SIC's with the most magical amp
I have ever heard!!!!

I have heard every KIND of speaker out there...not every speaker mind you...
but examples of the different speaker strategies...there is something for everyone
depending on your taste and musical preference...

I am still experimenting with different speaker approaches...however Deb and I
are thrilled with the SIC's in combination with the RM245.1 SET amp...more
thrilled than with anything I have ever heard...and like I said, I have heard
quite a lot out there...listening to music in our home has turned into something
quite extraordinary...

Warm Regards -Richard-

[Dmason]

Richard

That certainly resolves your take on what resolution means to you. I too like the idea of resolution in one's ear being comparable to actual instruments played in actual venues, in real time. -An almost archaic concept, it seems...

I would imagine serious consideration has to go to the fact that Mr Modjeski, The Wizard of Thermionia, actually winds his own transformers, to get things right the first time. That might increase resolution somewhat beyond whatever, and wherever the previous poster was referring to. Or has experienced, mind you...

I think I need to consider taking the plunge, and make my way through that smouldering crater known as L.A, and come and bask in this swirling cloud of harmonic wonder.  I am very happy for you and Deb. Did you bring the EML 45 tubes?

[-Richard-]

Hi Dan,

Always a great pleasure to hear from you. I was mentioning you to Roger
and he told me that he has read some of your posts:

"...I've been reading DMasons posts, and I respect his writing.
Seems like a sensible guy."

Thought you might like to read that...

I started listening with a matched pair of used Sylvania 45 tubes that Roger provided
for me...originally I thought the Emission Lab tubes were a bit too aggressive...
the Sylvania 45's were so s-m-o-o-t-h and creamy sounding and yet it still had
tight resolution in the bass...but when I switched back to the EML 45's, it was clear
that the Sylvania tubes did not have the same upper frequency resolution...
and after listening for several hours the EML tubes seemed to finally burned-in...
they are relatively new...and now the all-over sound is incredibly dynamic and
fully saturated with a rich timbrel palette of harmonic textures and colors...

However, it is amazing how well the small 1930's Sylvania 45's sounded...on
voice I might still give them the edge...a natural warmth that is addicting...
still, the EML's are extraordinary and bring music to life on CD's that Deb and I had
long ago relegated to the un-listenable periphery of our CD collection...actually
they now sound fabulous...ahhhhh...what an amp of this magnitude of refinement
and fire will do for our lowly CD's is not to be believed...

Again, great to hear from you, Dan...your original research and your own
explorations into the science and mysteries of Open Baffle design is what
got me and so many other audio enthusiasts off the commercial speaker
habit and into a new paradigm of DIY Open Baffle explorations...at an investment
of $300. I am listening to sound that commercial boxed speakers cannot reproduce
at the cost of thousands and thousands of dollars...

Warm Regards -Richard-

[Dmason]

I think the old tubes sound the best of all. The EML's are just the exception, which is why I love them. Some of the old tetrodes like 1625 are jaw droppingly good. My little 6DN7 SET using TV sweep tubes holds its own with the 45 amp, believe me.

Mr Modjeski, if you are reading, I think something like a PP triode using any one of the sweep tubes, available literally in the millions, for a few dollars would be a killer design sonically. You would have something very close to the 45, with alittle more bite, to round out your fantastic offerings. 4, 4-6PP, 35EL84, 100KT88 etc wpc... Just thinking out loud.

[Dr. Krull]

Richard, are you the same "Richard" who used to work for Roger Modjeski?  Just curious.

-Krull

[-Richard-]

Hi Krull,

I never worked for Roger Modjeski. By profession I am a designer and I have taught
a multitude of courses in 2 departments at Parsons School of Design in NYC
for almost 20 years before I moved Ojai, California. I heard about Roger through
Louis Chochos of Omega speakers. Louis really knows tube amps intimately,
and we converse from time to time on what is out there and who is doing what
with what tubes....he mentioned that Roger had just finished designing a 45 SET
amp that looked beautiful...and he also mentioned that he respected Roger
very much and thought his 45 amp might be spectacular...

I went to Rogers web sight and saw his RM 245 SET and feel in love with it...
it was way too expensive for the likes of me but since Roger lived close to me in
Santa Barbara...perhaps 1 hour away...I thought I would call him and mention that
I had just built a pair of Open Baffle speakers using the Visaton B200 drivers and
that I would love to hear his new 45 SET amp playing them...

Roger is always the intrepid scientist and he said alright...so I visited him in his
home/lab and we played my OB's with his RM 245 SET...frankely I was in a state
of shock...it sounded quite extraordinary...as we got to talking Roger mentioned
that he was working on a much less expensive version of his flagship
RM 245 SET amp...which sells for $6000...that he projected would cost less
than $2000. and I was immediately intrigued...he also said he was working on
designs that would give us all the control of his expensive flagship 45...which
really excited me...

Roger and I have been in touch ever since and a week or so ago he mentioned
that the first real production run of his new RM 245.1 SET was now available...

So I went down to see him and brought my new OB's with the Hawthorne Silver
Iris Coaxial drivers...this is Darrel's web site:

http://www.hawthorneaudio.com/drivers.htm

My unfolding friendship with Roger has created a ground for an understanding
of amplifiers and speakers that is exponentially of a far greater magnitude
than anything I would have thought possible...I deeply appreciate Roger's genius
and gifts...he is the most well-rounded, articulate, enthusiastic and penetrating
audio designer I have ever met...

Warm Regards -Richard-

[Dr. Krull]

Thanks for your response, Richard.  I have also owned some of Roger's equipment over the years and think it's  the best kept secret in the marketplace.  I have not personally met Roger but my email and phone conversations with him have always been highly enlightening.

-Krull

[JLM]

Richard,

My audition of the Silver Iris drivers came after they had been in use for one week with poor connecting wiring and CD source.  We used an old Scott integrated, my modified Clari-T, and a Citation 16.  Except for the expected reticent bass response from the Scott, there was little difference in amps via the Silver Iris drivers.  Furthermore, the recent modifications to my Clari-T was immediately obvious on my Bob Brines FTA-2000 speakers that use a single Fostex F200A driver per cabinet, but I heard none of the advantages through the Silver Iris drivers.

I agree, there is a level of detail that should be avoided as it can distract from the inner essence of the music.  But the Silver Iris drivers made everything sound like I had a head cold.  They made music easy to listen to, but also easy to live without.

[-Richard-]

Hi Dr. Krull,

It is nice to read your positive experiences of Roger's amplifiers...

You are right about Roger's work being one of "the best kept secrets in the
audio markets"...an astute observation and praise indeed!!!

In my way of thinking it is the small individual audio designer like Roger Modjeski
who possesses the kind of personal integrity and creates the kind of excellence of
performance that makes involvement in this hobby so deeply satisfying...

I have no love for mass produced corporate junk...even if the price tag shouts
conspicuous consumption all over it!

Being a designer myself I have an infinite respect and love for their creations...
My wife is also a designer and Deborah is just as deeply affected by a high level
of aesthetics like the look and feel of Roger's new 45 amps as I am...

And it's created and made right here in America!!!!
Am I indulging in some form of patriotism? Not at all!
We Americans can produce products that are exquisitely designed and that
perform on the highest level...why not acknowledge it with our purchases when
the situation fits...

And I am just as thrilled that Darrel Hawthorne is developing an entire line of
Open Baffle speakers...Darrel is an extraordinary fellow...he is a master of the
Shakuhachi Japanese flute...one of the most difficult instruments to master
in the world...and he has built an enormous array of esoteric horn speakers
before he began to develop his simple and inexpensive OB drivers
and complete speakers...he has a highly sophisticated understanding of the
potential for audio to sound extraordinary...for $300. you can experience
something unequaled by any other offering out there...and join the OB revolution!!!!

Darrel is a wonderful friend to people like us...audio and music lovers
that want the very best sound for the least money...most of us on Audio Circle
have limited budgets...so we must shop around very carefully and really get to
see and read everything we can before we finalize our purchases...

I recommend that everyone should get to know Roger's new 245.1 SET amp if
you have sensitive speakers...say from 92 db upwards...and take a look
at Darrel Hawthorne's Open Baffle drivers...together they make magic happen...

Warm Regards -Richard-

[Roger A. Modjeski]

Thanks DMason for reminding me about those tubes I put up in the attic years ago. To clairfy, we are talking about low impedance triodes here used for VERTICAL sweep, not the Horizontal tubes with the plate caps like the PL909, 6LF6 and the like. Those behave more like switches.

The vertical sweep circuit is in essence a class A single ended amplifier with low distortion... sound familiar? Just think, as kids we were WATCHING our SET amplifiers instead of listening to them. These tubes are linear down to a few percent and capable of good damping, wide bandwidth and low distortion, all without feedback of any kind. For those of you who noticed, if the vertical sweep tube was weak or the linearity control on the back of the TV was mis-adjusted, the lines would not be equally spaced and a person would look stretched or squashed as a result. This was a wonderful visual display of 2nd harmonic distortion. I hope many of you will "SEE" the analogy.

Please refrain from calling any of these formentioned tubes "VIDEO TUBES" just because they were used in TV sets. I have seen that in too many articles. This confuses them with the actual VIDEO amplifier which was another part of the TV.

I was fortunate enough to work in a TV repair shop from age 16 through my college years. I do remember a few burned fingers, those little guys run hot. But they lasted a long time.

Roger