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Jeffrey D. Medwin

Thinking of doing a Dynaco / DYNA PAS Preamp

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1 hour ago, Jeffrey D. Medwin said:

Certain things you can not easily control, but ...

 

 

IF you can, make improvements in areas you can control, and you can verify them, by listening. 

 

Then one must set-aside one's proven-to-be-false logic, and go with what you hear. ... make the improvement.

My question was only partly in jest, because if you truly believe that having an integer multiple of 9.52 feet for the power cord to the amplifier makes a substantial difference to sound, then it would not be too much of a hassle for you to get your house mains supply redone so that you had an integer multiple of 9.52 feet between the breaker box and the power socket where your amplifier plugs in.  Maybe you would achieve a yet higher level of audio nirvana?

 

Of course it sounds absurd, and indeed it is absurd, to do that. For exactly the same reason that your insistence on precisely 9.52 feet for the power cord is absurd.

 

And this also raises another question,again serving to highlight the absurdity of it all. Since you specify the length of the power cord to two decimal places, that means you are specifying it to about one tenth of an inch. Where exactly are you measuring from, and to, in your power cord?  Are you including the length of the spade connectors in the power plug, for example?

 

Surely you can appreciate how absolutely ridiculous your professed adherence to this Fulton nonsense is?

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Thanks to Sakuma San, there is just enough information to set-up the 9 inch version of this tonearm on my Musicmaster "Point One Five" idler drive TT.

 

http://www10.big.or.jp/~dh/codo/arm/arm.html

 

Joe Esmilla uses a Velvet Touch tonearm...or a couple...

 

velvet.jpg

 

Yeah, it's a gorny looking old primitive dinosaur. Mine uses a Stanton/Pickering 380  stereo cartridge.

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On 6/11/2020 at 3:45 PM, Dr. Gary said:

You said "Earlier this year, after I converted the solid state Bob Fulton BRAVURA Phono / Line preamp, to brass washer-pyramids - to support the unit's two power transformers,

Mahalia was doing remarkably better in playback resolution, though my VOTT A7-8s...... going from rubber to brass pyramids !!.   

Then, I sadly blew the preamp up,  while adding silver wire to augment the unit's energy-transfer-efficiency.  What a shame. 

My goal, and expectation, is that THIS new all tube preamp will smoke that old preamp in spades, from the very first fire up. But I won't know.....  till Mahalia Jackson sings to me from that 1958 LP !!  What a thrill, if my goal is met.   That dual mono Bob Fulton Bravura .....was no slouch ."

 

For starters, maybe you should give credit where credit is due.  The front panel of the  Bravura preamp that  you blew up says "Nexus Engineering" which was a company that was owned by the late John Tuttle who happens to be the engineer who designed the Bravura preamp.   http://www.audiocircuit.com/Home-Audio/Fulton

Bob Fulton may have added a few bypass capacitors here and there  and added a  few resistors to increase the gain of the phono stage in the Bravura that you blew up, but Bob Fulton DID NOT design the Bravura Preamp. 

 

Now, turning to your assertion that "THIS new all tube [reword this, you can make your point in a more civil tone, thanks the mods]

 

You joined in March, welcome to the forum, and have about 20 posts and every single one of them is a reply to the same person, and is negative.

 

This one is nearly a repeat of one you posted back in March about fixing his Bravura preamp for him and telling him not to mess around with it. Well I guess we know how that turned out, but you have made your point on this Fulton/Tuttle thing, and everything else seems to be a personal shot at Jeffrey (of course he leaves a lot open on that end).

 

I edited this post to remove the personal stuff and Jeff didn't respond, he left it alone, and kept posting progress on this preamp and then there is another shot from you, and Jeff responds and we have a couple of 2 year olds going back and forth.

 

I'm leaving the one I quoted above, but I'm deleting all of the personal stuff between the two you you. I hid the one back in March in different section, different thread, that got repeated 3 months later in this section. One is enough.

 

From my perspective you are going way out of your way to try and belittle someone. We get it, don't worry,  no one is going to start cutting cords or start swapping parts. They are just content to follow along the build,  or not, and leave it at that.

 

Respectful, constructive criticism/discussion has always been welcome here, but we don't abide people dropping in from time to time just to take a swipe at someone.

 

I don't need/want a response from either of you on this, obviously something goes way back from elsewhere, and it's way more appropriate for a PM. directly to each other, or if there is a question you can send it to me directly.

 

Thanks,

 

Travis

 

 

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12 hours ago, Jeffrey D. Medwin said:

ITS THAT SIMPLE. !!  

Not really. 

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Jeffrey, I do have another question as I try to follow your philosophy.  Are you using fractional sizes of Fulton length wires in your builds?  For example, when installing new leads on transformers, the leads from your input jacks, etc.  If not, why do you find that unnecessary?  
 

 

Maynard

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3 hours ago, dwilawyer said:

Not really. 

 

I'm glad you're compensated for this job.  Do they match you in your Klipsch 401K?

 

:ph34r2:

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7 hours ago, tube fanatic said:

Jeffrey, I do have another question as I try to follow your philosophy.  Are you using fractional sizes of Fulton length wires in your builds?  For example, when installing new leads on transformers, the leads from your input jacks, etc.  If not, why do you find that unnecessary?  
 

 

Maynard

 

 

Nice thoughtful question Maynard.  I have used divisors of 57 1/8th from time to time, but NOT on a consistent basis.  ( 28 1/2, 14 1/4, 7 1/8th inches ) 

 

Two inconsistencies :  (1) I don't always THINK of applying it, and (2) there are situations, where it is physically cumbersome to apply the idea.

 

My second audio mentor, Mr. Dennis Fraker, impresses upon me that multiple wire lengths should be precisely equal to each other, when paralleling wires ( which we often do ) , or, when using two wires coming from the same point.   

 

For example, in this preamp build, I can refer to the two blue 14 AWG lead outs coming from the Power Transformer's High Voltage secondary, to each 5AR4/GZ34.  Those two lead outs are precisely equal.  The GZ34 connection distances are not. .  See the GZ34 photos as an example, but I have re-centered the incoming attachment leads better since that posted photo, was taken.

 

Dennis has taught me to never dog leg, from one tie or use-point to another.  Instead, connect the two use-points together with a single lead, and attach the incoming lead as closely to the center, as you can see it.  That way, each use-point has EQUAL lead lengths feeding them.  

 

Jeff  

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6 hours ago, mike stehr said:

Thanks to Sakuma San, there is just enough information to set-up the 9 inch version of this tonearm on my Musicmaster "Point One Five" idler drive TT.

 

http://www10.big.or.jp/~dh/codo/arm/arm.html

 

Joe Esmilla uses a Velvet Touch tonearm...or a couple...

 

velvet.jpg

 

Yeah, it's a gorny looking old primitive dinosaur. Mine uses a Stanton/Pickering 380  stereo cartridge.

 

 

Mike !!

 

How do you like your idler drive?  I have a decent belt drive, but I always wonder, in the back of my mind,  if I should re-do something like a Lenco 75 !! 

 

Any thoughts you'd like to share?  I need to look up your table, next.

 

Jeff 

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4 hours ago, Coytee said:

 

I'm glad you're compensated for this job.  Do they match you in your Klipsch 401K?

 

:ph34r2:

Yes 3 for 1 up to 5 point something to achieve a golden ratio.

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9 hours ago, mike stehr said:

Joe Esmilla uses a Velvet Touch tonearm...or a couple...

 

Yup, looks like a Japanese Gray Research clone...I've even seen some mounting templates on eBay...

 

 

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3 hours ago, Jeffrey D. Medwin said:

My second audio mentor, Mr. Dennis Fraker, impresses upon me that multiple wire lengths should be precisely equal to each other, when paralleling wires ( which we often do ) , or, when using two wires coming from the same point. 

What's that mean? Precisely equal. What's the tolerance? 

 

Tenth of an inch, hundredth, thousandth?

 

Should you cross check by weight, down to a microgram?

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Lets just take out the word "precisely".  Equal wire lengths will do fine.

 

Thanks, 

 

Jeff 

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5 hours ago, Jeffrey D. Medwin said:

How do you like your idler drive?  I have a decent belt drive, but I always wonder, in the back of my mind,  if I should re-do something like a Lenco 75 !! 

 

Any thoughts you'd like to share?  I need to look up your table, next.

 

I was using a Dual turntable prior to the idler drive. The dual worked fine, with a good sound...but I'm sensitive to pitch control, and the cheap belt drives always seem to have that issue. The belt was starting to wear out on the Dual, and I was thinking of buying another. But then I recalled the Musicmaster TT I had purchased with the Altec amp and other gear, that I had stashed in the back room for a good year.

 

So I brought it out, cleaned it up, looked over the rubber on the idler wheel, which was still soft with no flat spots.

Gave the old turntable a try...I was surprised at how much more big and open the Musicmaster sound was compared to the Dual. The midrange especially.

 

I tore it down, re-lubed everything, fixed the spindle to pivot distance, and leveled the arm more even with the platter. I even bought another idler wheel from eBay some seller custom made for the KS Musicmaster, but the old one still works fine.

No plastic in this beast. A stupid simple design which uses a magnetic eddy brake sort of thing for pitch control and it works very well.

 

There is the usual isolation problems which gives some platter growl...it's an ongoing project. But the rumble is rather subtle.

 

I've listened to a VPI Scout vacuum platter TT with a Shelter cart. Beautiful analog sound, but the old Musicmaster with all it's warts still gets my feet tapping.

I use a Scott LK-48B for the tube phono stage the Scott has. This turntable seems to sound best with a tube phono stage, over the vintage cheap SS receivers I have.

 

I have built a tube phono stage preamplifier based on the passive RCA circuit with 12AX7, but wasn't too thrilled with the result as compared to using the Scott.

The use of tone controls and the mono switch are nice options to myself, along with an occasional bass boost for the weak records.

 

But I still need to build a separate tube phono stage...

 

post-6643-1381952590103_thumb.jpg

 

 

 

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I'm glad to hear this.  I just measured mine and they're 9.38.  I was starting to get the jitters and thought about cutting them to pieces.

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12 hours ago, Jeffrey D. Medwin said:

Lets just take out the word "precisely".  Equal wire lengths will do fine.

 

Thanks, 

 

Jeff 

How equal? 1% close enough?

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10 hours ago, Dr. Gary said:

That length agrees to within a small  fraction of an inch to the length of one of Fulton's RCA-RCA  interconnect cables that I still have.    Likewise, the standard nominal lengths of the speaker cables that Fulton sold  (14,  28 and 57 feet) are also integral multiples of the that 57.2 inch length.  

Now, applying the official FMI 4.77-foot reference length to power cords, the 9.52-foot power cord that Fulton allegedly installed on his personal Bravura preamp is almost

So if it didn't have any theoretical sonic/audio benefit, was it to squeeze a little extra profits out? Selling 4.77 for same price as 5', 14 for 15', 28' for 30' price and 57' for 60'? Or did he simply have 9..52' of power cord left on the roll and that's what it was going to be?

 

Or was he looking for a gimmick/marketing hook?  Like swapping "K" for "C" on product names?

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15 hours ago, dwilawyer said:

So if it didn't have any theoretical sonic/audio benefit, was it to squeeze a little extra profits out? Selling 4.77 for same price as 5', 14 for 15', 28' for 30' price and 57' for 60'? Or did he simply have 9..52' of power cord left on the roll and that's what it was going to be?

 

Or was he looking for a gimmick/marketing hook?  Like swapping "K" for "C" on product names?

 

 

First of all, where did you get the idea that what Mr. Fulton developed " didn't have any theoretical sonic/audio benefit ". 

 

Just because YOU do not understand something, or can accept it, does not mean it is not true !! 

 

Golly, you are an attorney.  I would think, an analogy of your mind - set is just like .................assuming someone is guilty, before the trial, rather than innocent.

 

Secondly, Robert was VERY talented in the use of measuring equipment .  Recall from the FMI memorial web page, biography, the Tektronix Reps would go to him, to find ways to sell their O'scope measuring equipment to potential users.  RWF knew, better than anyone else, how to get the most from such equipment, so it seems.

 

Recall, from my 2019 SE KT88 thread, how I brought up that in the mid 1980s, RWF was using a 2 GIG O'scope to measure audio.  Recall how " Mr. E.E. " a  fairly sophisticated / highly experienced E.E., and most other E.Es, could NOT wrap their head and mind around the fact that audio is wide band !!  Almost forty years later. 

 

Finally, there is one HUGE overriding fact about Robert, that can never be forgotten, nor minimized.  Robert was a Christian, and he lived his convictions !!! 

 

He named his own Recording Company " Christian Dynamics ".  When he and his V.P. came from Minneapolis to California, to modify my Premiere ( large ) loudspeakers, these two gentlemen got down on their knees, on my living room floor, and prayed - before they ever proceeded to change the crossover.  How many people, will do that ?? 

 

Do you really think its possible that people who respect GOD, and try to act God-Like, will tell lies to market audio equipment Travis?? I don't.

 

What I personally witnessed as his character, over the ten last years of his life, had a LARGE effect upon me, and it was all positive. 

 

To put it in easily-understandable terms, it would be like someone saying " PWK was a shyster, and all he did was fool the public, to his advantage ".    I don't think that would go over too well, ...........sit too well, with many people who actually knew PWK. 

 

I hope I do not have to talk about this - anymore. 

 

You have been sent P.M.

 

Jeffrey Medwin

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1 hour ago, Jeffrey D. Medwin said:

First of all, where did you get the idea that what Mr. Fulton developed " didn't have any theoretical sonic/audio benefit". 

 

From this response: "According to my notes from a phone conversation on 8/20/1982 that I had with Jack Anderson who worked for Bob Fulton at that time , the official FMI Wire Reference Length was 57.2 inches or equivalently 4.77 feet.    That length agrees to within a small  fraction of an inch to the length of one of Fulton's RCA-RCA  interconnect cables that I still have. "

 

And, 

  "Another would be that Fulton wanted to avoid the possibility of having to use an extension cord of arbitrary and uncertain length when demonstrating his speakers at various audio shows 

And, "now for the disclaimer......the sole purpose of the above information is to provide the history that is likely behind the seemingly-mysterious 9,52-foot power cord that Fulton allegedly installed in his personal Bravura preamp, and has no relevance whatsoever to the absurd claim by some that use of a 9.52-foot power cord provides a sonic benefit."

 

I wasn't sure what Dr. Gary's point was . . .that there was something presumably significant about the FMI Wire reference length, but not the power cord.

 

I will move all of this to a different thread so it doesn't clutter your build thread.

 

Travis

 

 

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