Mass Loading, Part TWO, and a Retraction on the Type 46 tube suggestion

dowto1000

Junior Member
I have had a brand-new audio discovery, that has become (a) interesting, (b) frustrating, (c) very disappointing, and (d) very exciting, ( all 4 of these, at ONE time!! ) over the last two days of listening.

I would like to share my listening results and impressions with others, anyone who may be interested in the high end, and obtaining the best possible performance, with tube amps, that we can get.

The bottom line is, I can no longer recommend the TYPE 46 tube as being audio-suitable, to anyone seeking the ultimate truth in audio playback.

I happened to write last week about the ALTEC 604's time alignment, and why the GPA 604 will easily outperform ALL the prior ( vintage ) 604s. Nate, was smart and kind enough to immediately pick up on this, and for everyone's benefit, he cut and pasted 604 driver " depth " diagrams, for all to see, and hopefully .....understand.

As a result Nate's follow-up post, and his comment I read in his post - about differences in distances making a large sonic difference, I THOUGHT about my own 1 1/2 year old VOTT ( A7-800 ) living-room set up. I recalled when I went to the Emilar EH-500 cloned horns, I NEVER ever carefully time aligned the the 802D tweeter driver and tweeter horn, to my 515B woofer driver and bass horn.

I also have had a " feeling", all along, for several months now, that my system balance was wrong and has been incorrect, with the highs overpowering the lows and mids.

OK boys and girls, out came a easy-to-read ruler, and I started systematically listening to distances, from the front edge of the 825 bass enclosure, to the tweeter horn's front flange.

Used my Pioneer Blu Ray player, ( top of the line BDP-09FD ) directly into the mass loaded Type 46 SET amp. Turns out, I was WAY too far forward on the tweeter horn. over an inch !!! No wonder the highs were" forward sounding " to me. They literally were !! I was able to easily select a good compromise distance, to time align the tweeter to the woofer. I was able to resolve / hear the optimal distance, by ear, to 1 millimeter easily.

I was a happy camper, getting the time alignment correct, and hearing my six reference CDs played back for the first time, with better balance. BUT BUT BUT...............

The more I listened, the more MAD I got.

Why, EVERY note I heard, had a fuzziness, a lack of purity to it, every single note, guitar, piano, etc.

I had built this 46 SET amp six months ago for a audio-friend, and was thrilled with how it plays more linearly, powering the speaker, in the middle midrange, than my prior 2016-2017 two Type 45 amps ( with the same circuit ). I sold off every one my ST type 45s.

WHY am I hearing a fuzziness on each note, last two days, its so obvious wrong-sounding to me.???

The answer I figured out yesterday, and it was confirmed today. The Type 46, a directly heated tube, has an extra grid in it, its a four element tube "triode connected ". So, it NEVER can play with the purity I hear of a true triode, such as the JJ 2A3-40 amps, which I just heard at RMAF three weeks ago, for three full days, or, the JJ 2A3-40 dual mono amp, I prototyped in December, 2016, and listened to for three weeks before tearing it down.

WHY am "I" ( and no one else ) so suddenly hearing this "fuzziness", last two days, and getting MAD ??

Two reasons me thinks :

(1) Because I have mass loaded by ear, the Type 46 amp. By placing a brick close to the tube socket of each 12AX7 driver tube, and systematically A-Bing this, I eliminated a physical intermodulation, easily heard on A-Bing, a blurring of the high gain driver stage, as it powered the 46 finals tube. The simple building brick eliminated physical vibrations. Definition became razor - sharp.

Plus,

(2) my DIY amp's driver stage, ( unlike any SET amp I know of - except one) has its B+ fully and heavily shunt regulated, for stability. With ONE single passive part, I draw over TEN times more current through the shunt, than the audio tube uses.

So, my front end has stability of the B+, ( as the driver tube processes the input signal's audio content ) which no other SET amp design ( except one ) , in the history of tube audio to my knowledge, has ever had.

So, boys and girls, I am hearing the fuzziness, and the truth, and I have LEARNED something here. As Mr. Robert Futon used to say to me about using real triodes " there is no substitute for the real thing ".

Historically, Western Electric, ( we all should know ), got kicked out of the movie theatres because of hearing two taps when there was one on the screen. This was for two reasons : Even though the WE 91 amp had a 300B ( true triode ) output stage, the driver was a non triode, a 310 pentode. The second reason was, the WE speakers were not time-aligned, whereas the ALTEC speakers, that replaced the WE speakers, were time-aligned. We can learn from history !!

I learned, by directly experiencing this, last couple of days. There is NOTHING like a direct listening experience, to learn what works and doesn't work !! To heck with theory !!

I would say, 99% of the people running commonly designed middle-fidelity SETs will have a hard, if not impossible time, hearing what I have experienced the last two days. ( Ditto for the shallow but broad suck out I hear on a SE TYPE 45 tube , which HAS triode "purity" to fool you, and a suck out ) .

My Kansas City " firehouse" friend ( with ALTEC A4s, and his dwelling was built 1911, decommissioned in 1933 because door wasn’t tall enough to handle trucks instead of horses.) , heard my system - came over for the first time just yesterday, and he agrees fully with what I am hearing and describing to you all.

Well, live and learn. I am excited to be alive, and be able to report all this to you. Maybe it will be of benefit to ....who knows who, or how many people, in their audio / listening futures.

GOD bless you all.


Dowto1000
 
Last edited:

Redboy

Knobophobe
Hey, Jeff. Cool that you could squeeze a little more out of your speakers by simply moving them around a tiny bit... That's what I call a low-cost tweak! :)

I'm not quite ready to abandon my hoard of 46s, though... Did you try a different pair of outputs to rule out an ailing tube? I have a lot of globe 46s in my collection, and have come across a few that (sadly) are possessed by audio gremlins - probably a mechanical vibration manifested as noise.

Also, can you explain a little more about this "single part shunt regulated B+" of yours? You've mentioned it a couple times now (and I saw a close-up of some parts), but I'm slow on the uptake...
 

dowto1000

Junior Member
Hey, Jeff. Cool that you could squeeze a little more out of your speakers by simply moving them around a tiny bit... That's what I call a low-cost tweak! :)

I'm not quite ready to abandon my hoard of 46s, though... Did you try a different pair of outputs to rule out an ailing tube? I have a lot of globe 46s in my collection, and have come across a few that (sadly) are possessed by audio gremlins - probably a mechanical vibration manifested as noise.

Also, can you explain a little more about this "single part shunt regulated B+" of yours? You've mentioned it a couple times now (and I saw a close-up of some parts), but I'm slow on the uptake...


Thanks Nate,

Your follow up comment and post to mine, helped me, reminded me to do what I had forgotten to do.

The Shunt idea for this is simply not mine .....to disclose !!

See if you can THINK about what single part would create a one part shunt regulator, for 1/2 a 12 AX 7 with a 360 VDC B+ supply, the tube section drawing, say 1 mA. ?? Think about that for a day or three ....Nate !!

I can easily, and will try other 46s, but I am " 97% sure " about what I posted.

These were brand new tubes ( NOS, NIB, thump-tested by ear, by a musician friend! - for minimal internal noise, second best pair of ten NIB tubes ) , six months ago. I loaf them at 62% their 10 Watt maximum rating !!! The fuzziness occurred immediately after the mass loading, and I have listened for two days, so has, independently, my ALTEC 1911 firehouse friend who visited. !! :-)

Nate, have you ever had JJ 2A3-40s at home, in a pair of your amps??


Dowto1000
 
Last edited:

opa1

Moderator
Staff member
Do you think that with the chassis now mass loaded that the tube socket and tube might be absorbing the vibrations?
 

dowto1000

Junior Member
No, just the opposite of what you are thinking, is my result and listening experience.

The mass loading absorbs the vibrations from the power transformer, airborne waves, etc., quiets the chassis, and allows the tube to be FAR more true to the input signal it sees on the grid. This, I A-Bed and easily - was able to hear.

My VOTT speakers are also mass loaded, about 400 pounds each. Much nicer speaker clarity as a result of this !! As I was time aligning my horns a day or so ago, I re-A-Bed the four concrete pavers on the tweeter horns, one at a time, and they are needed, better !! About 50 pounds total was good on the tweeter horns, did it in four 12 pound increments, A-Bing each, back and forth !! :-)

Fun, and very exciting to hear, and think-about afterwards.

Dowto1000

Photo is an earlier implementation, with three gray pavers on top of the horn. P1010010.JPG This early photo's arrangement was improved, far better implemented, several months ago, and then, ' went to four gray pavers on top of the tweeter horn, by ear.
 
Last edited:

Redboy

Knobophobe
These were brand new tubes ( NOS, NIB, thump-tested by ear, by a musician friend! - for minimal internal noise, second best pair of ten NIB tubes ) , six months ago. I loaf them at 62% their 10 Watt maximum rating !!! The fuzziness occurred immediately after the mass loading, and I have listened for two days, as has, independently, my ALTEC 1911 firehouse friend who visited. !! :-)
Well, be sure to drop another set in there, just in case... :) It would be an easy win!

Nate, have you ever had JJ 2A3-40s at home, in a pair of your amps??
Nope. Not yet.
 

Kyle

Junior Member
Historically, Western Electric, ( we all should know ), got kicked out of the movie theatres because of hearing two taps when there was one on the screen. This was for two reasons : Even though the WE 91 amp had a 300B ( true triode ) output stage, the driver was a non triode, a 310 pentode. The second reason was, the WE speakers were not time-aligned, whereas the ALTEC speakers, that replaced the WE speakers, were time-aligned. We can learn from history !!

Dowto1000

Learning from history involves learning about history. WE was never kicked out of movie theaters, they were litigated out of theaters.
This passage is from the Altec Wikipedia entry but it's available in several locations that have documentary proof - not hearsay.
https://en.wikipedia.org/wiki/Altec_Lansing

"In 1930, AT&T's Western Electric established a division to install and service loudspeakers and electronic products for motion picture use. Named Electrical Research Products, Inc. and commonly referred to by the acronym ERPI, it was the target of an anti-trust suit brought by Stanley K. Oldden.[9] By 1936, Western Electric had shed its audio equipment manufacturing and sales division, bought by International Projector and Motiograph, and was looking to dissolve the associated service division. ERPI was purchased as part of a consent decree in 1937 by a group of ERPI executives, including George Carrington, Sr., Leon Whitney "Mike" Conrow, Bert Sanford, Jr., and Alvis A. Ward, with funding from three Wall Street investors. They reincorporated as "Altec Service Company", the "Altec" standing for "all technical".[10] Company executives promised they would never make or sell audio equipment.[10]

The Altec Services Company purchased the nearly bankrupt Lansing Manufacturing Company and melded the two names, forming the Altec Lansing Corporation on May 1, 1941. The first Altec Lansing power amplifier, Model 142B, was produced that same year. James Bullough Lansing worked for Altec Lansing, then in 1946 he left to found the James B. Lansing Company (JBL), another manufacturer of high-quality professional loudspeakers, which competed with Altec Lansing."


I'm not trying to be a dick but it's one thing to have an opinion on sound quality and another to rewrite historical facts.
 

TubeHiFiNut

Administrator
Learning from history involves learning about history. WE was never kicked out of movie theaters, they were litigated out of theaters.
This passage is from the Altec Wikipedia entry but it's available in several locations that have documentary proof - not hearsay.
https://en.wikipedia.org/wiki/Altec_Lansing

"In 1930, AT&T's Western Electric established a division to install and service loudspeakers and electronic products for motion picture use. Named Electrical Research Products, Inc. and commonly referred to by the acronym ERPI, it was the target of an anti-trust suit brought by Stanley K. Oldden.[9] By 1936, Western Electric had shed its audio equipment manufacturing and sales division, bought by International Projector and Motiograph, and was looking to dissolve the associated service division. ERPI was purchased as part of a consent decree in 1937 by a group of ERPI executives, including George Carrington, Sr., Leon Whitney "Mike" Conrow, Bert Sanford, Jr., and Alvis A. Ward, with funding from three Wall Street investors. They reincorporated as "Altec Service Company", the "Altec" standing for "all technical".[10] Company executives promised they would never make or sell audio equipment.[10]

The Altec Services Company purchased the nearly bankrupt Lansing Manufacturing Company and melded the two names, forming the Altec Lansing Corporation on May 1, 1941. The first Altec Lansing power amplifier, Model 142B, was produced that same year. James Bullough Lansing worked for Altec Lansing, then in 1946 he left to found the James B. Lansing Company (JBL), another manufacturer of high-quality professional loudspeakers, which competed with Altec Lansing."


I'm not trying to be a dick but it's one thing to have an opinion on sound quality and another to rewrite historical facts.

This was the first "divestiture" forced upon the WE/ATT/Bell System Monopoly. The final "divestiture" being Judge Green's Consent Decree, implemented on 1/1/1984.
 

dowto1000

Junior Member
It was a re
Learning from history involves learning about history. WE was never kicked out of movie theaters, they were litigated out of theaters.
This passage is from the Altec Wikipedia entry but it's available in several locations that have documentary proof - not hearsay.
https://en.wikipedia.org/wiki/Altec_Lansing

"In 1930, AT&T's Western Electric established a division to install and service loudspeakers and electronic products for motion picture use. Named Electrical Research Products, Inc. and commonly referred to by the acronym ERPI, it was the target of an anti-trust suit brought by Stanley K. Oldden.[9] By 1936, Western Electric had shed its audio equipment manufacturing and sales division, bought by International Projector and Motiograph, and was looking to dissolve the associated service division. ERPI was purchased as part of a consent decree in 1937 by a group of ERPI executives, including George Carrington, Sr., Leon Whitney "Mike" Conrow, Bert Sanford, Jr., and Alvis A. Ward, with funding from three Wall Street investors. They reincorporated as "Altec Service Company", the "Altec" standing for "all technical".[10] Company executives promised they would never make or sell audio equipment.[10]

The Altec Services Company purchased the nearly bankrupt Lansing Manufacturing Company and melded the two names, forming the Altec Lansing Corporation on May 1, 1941. The first Altec Lansing power amplifier, Model 142B, was produced that same year. James Bullough Lansing worked for Altec Lansing, then in 1946 he left to found the James B. Lansing Company (JBL), another manufacturer of high-quality professional loudspeakers, which competed with Altec Lansing."


I'm not trying to be a dick but it's one thing to have an opinion on sound quality and another to rewrite historical facts.


It is a report on my listening impressions, audio, and I did not try, nor have the time, to make it into a perfect document for posterity. Nor will I take the time to do so, others, such as you, may feel free to research and correct my writings, as you see fit. No problem. The fuzziness and hearing two taps, correspond to each other.

Here is the latest mass loading listening report, as of tonight's conclusion.

My Pioneer BDP-09FD is a 29 pound Blu Ray player, and I had added about 20 pounds of concrete to it, prior to this evening. Tonight, I incrementally added another about 40 pounds to it, carefully A-Bing, taking blocks on and off, while listening to the six CDs, always at the same volume ( full bore in) which I use as a reference.

Guess what, the extra mass helped. My acid test is piano, tone, weight, timbre / color, and dynamics, and, as of a few minutes ago, I feel its the best I have heard piano reproduction to date, so I am pleased to hear and report this to anyone who may be interested.

I will slip-in different NOS 46s tomorrow. I still hear tonight - the bad sounds I mentioned at the start of this thread. Swapping 46s will rule out both of these six-month-old tubes, running conservatively ( 62% ) from having been degraded all at once, equally ( both channels ) and simultaneously .

I am retiring for the night, with happy thoughts, very satisfied of what I just heard of piano tone and reproduction, for four dollars worth of patio paving blocks. It sort of has very much surprised me........pleasantly.

Live and learn.

Good night.

Best to all,


Dowto1000 ( which means, TZA, TVIX, SQQQ, buy at the market, 10-31-17, with 10% only of one's assets. )
 
Last edited:

marantzfan

Administrator
Staff member
There is certainly a lot of lore surrounding Altec, Western Electric and JBL from those days. Legends abound and with enough repetition on audio forums, some of it has nearly become accepted as fact.

Thanks for keeping the record straight @Kyle.
 

dowto1000

Junior Member
Yup. Occam's Razor and all that, eh, what? :)


Definition of Occam's razor. :a scientific and philosophical rule that entities should not be multiplied unnecessarily which is interpreted as requiring that the simplest of competing theories be preferred to the more complex or that explanations of unknown phenomena be sought first in terms of known quantities.

Dowto1000
 

dowto1000

Junior Member
There is certainly a lot of lore surrounding Altec, Western Electric and JBL from those days. Legends abound and with enough repetition on audio forums, some of it has nearly become accepted as fact.

Thanks for keeping the record straight @Kyle.


Yes, but realize my perspective : far more important to me, now, is what I hear in my living room, from my hi fi system experiments at home !! That which Kyle nicely researched is old news, this is new stuff for some of us, and possibly applicable to our high-efficiency systems.

Dowto1000
 

dowto1000

Junior Member
Redboy,

I swapped type 46 tubes today and listened.

AFAICT, I hear the same types of artifacts with the swapped-in pair of Type 46s. ( TV7 tested RCAs, measure 76 and 78 vs 50 )

Its a shame I currently have no other DC SET amps on hand, with JJ 2A3-40s in them. That will change............ as will the Avatar photo !! Two months or so.

Dowto1000
 

dowto1000

Junior Member
Post 11 of this thread....continued.....mass experiments, added more by ear :

Besides the 40 pounds additional added to the Pioneer Elite Blu Ray player last night, this morning I added about another 30 pounds to the already heavily-weighted SET amp.

So, its a total of 70 pounds additional weight added ...... the last 24 hours.

I ran out of bricks, so I employed an unused custom low DCR power transformers, a 20 pounder, on top of the amp's existing power transformer location.

Also on the SET amp, ' added a 10 pound power transformer, on top of an on-end brick nearby to my 12AX7 input / driver tube - .... was the front end of the amp. ( Not viewable in the photo below . )

The extra 30 pounds on the amp today, HELPED the presentation. More dynamic, lower in distortion, more resolution, more inner detail, was heard. Dusty Springfield's voice just got more REAL sounding , and surprisingly to me, more linear top to bottom, unmistakenly better, more real-sounding in the ultra-critical midrange, as I went back and forth, taking these extra weights on and off.

WHOOPIE. It was all totally unmistakable. I can actually bear to listen to digital now, with this extra mass loading on the source and the amp !!! Hallelujah.

My future course, and stereo in-home set up, is clear to me. I am pleased, and calmly excited....got it !!!

Lowes has all the pavers you would need to experiment, and it is superbly inexpensive. Other than eventually executing all this in a " neat manner "on my up-coming JJ 2A3-40 mono amps, and this existing Blue Ray player, I feel I am about done with this mass loading subject. I know what to do, from what I have heard directly. You can experiment next !! Have fun, I will and am.

Dowto1000


P1010030.JPG P1010029.JPG
 
Last edited:

TubeHiFiNut

Administrator
@dowto1000 - Jeff, I've got to admire your dedication to improving your system - practicality notwithstanding. :)

This is not something that I will ever be able to pull off in my home. Guess I'll just have to live vicariously through you on this one. :)
 

Redboy

Knobophobe
Some more questions, to be consumed with a small measure of salt... (tongue in cheek, maybe?). I'm playing devil's advocate here, to be clear.

Could it be that your mass loading exercise is actually a room-tuning experiment? By filling your room with pavers, you are certainly decreasing the room's volume somewhat...

I note that your listening and experimentation is occurring (primarily?) in the evening. This is also the time of day that my system starts sounding its best, when there's less "hash" and noise from the electrical grid.

Have you swapped out driver tubes, also?
 

dowto1000

Junior Member
P1010025.JPG
Some more questions, to be consumed with a small measure of salt... (tongue in cheek, maybe?). I'm playing devil's advocate here, to be clear.

Could it be that your mass loading exercise is actually a room-tuning experiment? By filling your room with pavers, you are certainly decreasing the room's volume somewhat...

- - - - - - - - - -



No, because the pavers are small in volume, and they are IN the room all de time, on, or off de amp !! Right ?? :-)

"I note that your listening and experimentation is occurring (primarily?) in the evening. This is also the time of day that my system starts sounding its best, when there's less "hash" and noise from the electrical grid."

Yes, but I listened today, this AM also. Its always better later in the day, for the reason you cited.

"Have you swapped out driver tubes, also?"

No.

The computed plate dissipation of each driver tube is about ( 180 VDC P-K times 0.0006 A. ) or, about 0.108 Watts , and the tube's maximum dissipation rating is 1.0 Watt. The tube is a premium 12AX7, loafing in-circuit, and it should not be the problem, should last 20-50,000 hours operating at one tenth of maximum dissipation .

I still say the problem is the extra grid in the TYPE 46, sounding to me somewhat like a pentode tube, triode connected, finally being heard ( blurred, fuzzy, unpure ) in a now-fairly high resolution , more optimized implementation.

* * * * * * * * * * * * * * * * * *

More tidbits :

Besides the amp's 10 to 1 front-end Shunt Regulation, 1,500 A. instantaneous-peak film caps ( 'same caps in the DIY speaker crossover ), six Ohm inductors, ........ I also do a " attended listening ", second AC switch on my personal amps, for my home listening.

The normal AC switch turns the unit off and on, through a fuse and a 90 Ohm slow-start- up thermistor , but a second "attended listening" AC switch eliminates the fuse and thermistor, so I can pull energy directly from the wall socket when listening ....sounds better that way . The AC power cord, a 114 1/4 inch Fulton Brown 10 AWG speaker wire, is hard-wired / soldered into the amp, 'never use a IEC.

This week's mass loading experiments - went hand-and-hand with the amp build, system wiring, and the A7-800s.

Dowto1000



Click on faint " Click To Expand ", right above, middle of the page.

Top Left Corner : two AC switches, fuse and a CL-90 thermistor, double 12 AWG ( 9 AWG ) hook-up wire for AC to power transformer, below deck. )
 
Last edited:
Top