How i voiced my open baffle speakers

5-18-22........................ DIY SPEAKER CABLES............................ ULTRA HIGH PERFORMANCE

The speaker cables that were made for Hari, in 2021, and were recently DIY built by Guderbrod Auidio, are made precisely as follows:

Wire: Military Specified m22759/11. This is multi stranded copper wire, silver plated, in a teflon outer jacket . Best source : APEX Jr. Surplus Electronics in California, USA. Steve is the shop owner - a good person !!

Configuration : Each polarity consists of three leads in parallel, 12 AWG + 12 AWG + 14 AWG. ( equivalent AWG is 8 AWG , thus this configuration provides a superb transfer efficiency. ) Terminate the ends into appropriate high quality spade terminals. Each polarity trio of 12 + 12 + 14, after spade lug termination, is twisted around each other, loosely - not tightly. Perhaps two inches per twist.

Lengths : Specifically cut the Mil Spec wire to two Robert Fulton wire lengths , or 57 1/8th inches times two, which is 114 1/4 inches. Do not cut amplifier-to-speaker leads shorter than two integrals, as this will sound worse.!!! Only if you absolutely require extra long leads, use three Fulton lengths. Cut the wires at 171 3/8ths inches long, all three per polarity equal in length.

114 1/4 inches is also best sounding length as a Power Cable, 12 AWG typically is used, with 20 A. IECs.

Implementation : Be absolutely sure, when in use, that the two twisted polarities do NOT ever touch each other, in their route from the amplifier to the speaker. Not even ONE time !!!! Do not lay wires on rugs, metal objects, or plastic surfaces, as it is a degrade in energy transmission.. It is best to float the two polarities, going from power amp to each speaker , in MID AIR, and not touching each other, or, other surfaces. ( Read Pierre Sprey, " Wire Management ".)

ADDITIONAL use : Once you come to understand what this wire does - musically, use this same Mil Spec wire from the crossover, typically inside your speaker, to the various drivers. Two times 12 AWG works very well to woofers. One times 14 AWG works well to midranges, and compression tweeters. Again, no-touch their polarities !! The best lengths from the crossover to the driver are one Fulton increment, 57 1/8th inches, OR one- half a Fulton increment , 28.56 inches.

This speaker wire configuration was developed by my Audio Mentor, Mr. Dennis Fraker of Livingston, Montana, USA.

Enjoy this.


Jeff

View attachment 69366
You state "Each polarity consists of three leads in parallel, 12 AWG + 12 AWG + 14 AWG. ( equivalent AWG is 8 AWG , thus this configuration provides a superb transfer efficiency."
What exactly is "transfer efficiency"? Where is it defined, and how is it measured and quantified?

You also state "Do not lay wires on rugs, metal objects, or plastic surfaces, as it is a degrade in energy transmission." What exactly is the nature of the degradation to which you refer, and how is that degradation measured and quantified?
 
5-18-22........................ DIY SPEAKER CABLES............................ ULTRA HIGH PERFORMANCE

The speaker cables that were made for Hari, in 2021, and were recently DIY built by Guderbrod Auidio, are made precisely as follows:

Wire: Military Specified m22759/11. This is multi stranded copper wire, silver plated, in a teflon outer jacket . Best source : APEX Jr. Surplus Electronics in California, USA. Steve is the shop owner - a good person !!

Configuration : Each polarity consists of three leads in parallel, 12 AWG + 12 AWG + 14 AWG. ( equivalent AWG is 8 AWG , thus this configuration provides a superb transfer efficiency. ) Terminate the ends into appropriate high quality spade terminals. Each polarity trio of 12 + 12 + 14, after spade lug termination, is twisted around each other, loosely - not tightly. Perhaps two inches per twist.

Lengths : Specifically cut the Mil Spec wire to two Robert Fulton wire lengths , or 57 1/8th inches times two, which is 114 1/4 inches. Do not cut amplifier-to-speaker leads shorter than two integrals, as this will sound worse.!!! Only if you absolutely require extra long leads, use three Fulton lengths. Cut the wires at 171 3/8ths inches long, all three per polarity equal in length.

114 1/4 inches is also best sounding length as a Power Cable, 12 AWG typically is used, with 20 A. IECs.

Implementation : Be absolutely sure, when in use, that the two twisted polarities do NOT ever touch each other, in their route from the amplifier to the speaker. Not even ONE time !!!! Do not lay wires on rugs, metal objects, or plastic surfaces, as it is a degrade in energy transmission.. It is best to float the two polarities, going from power amp to each speaker , in MID AIR, and not touching each other, or, other surfaces. ( Read Pierre Sprey, " Wire Management ".)

ADDITIONAL use : Once you come to understand what this wire does - musically, use this same Mil Spec wire from the crossover, typically inside your speaker, to the various drivers. Two times 12 AWG works very well to woofers. One times 14 AWG works well to midranges, and compression tweeters. Again, no-touch their polarities !! The best lengths from the crossover to the driver are one Fulton increment, 57 1/8th inches, OR one- half a Fulton increment , 28.56 inches.

This speaker wire configuration was developed by my Audio Mentor, Mr. Dennis Fraker of Livingston, Montana, USA.

Enjoy this.


Jeff

View attachment 69366

I would like to take this opportunity to offer some first-hand knowledge that I have regarding the lengths of Fulton cables. For starters, there is a minor discrepancy regarding the so-called "Fulton Length". According to my notes from a phone conversation that I had several decades ago with Jack Anderson, who worked for Fulton and who was involved with the fabrication of the Fulton interconnect and speaker cables, the reference length that I was told is 57.2 inches. Additionally, based on measurements of Fulton Interconnects and speaker cables that still have, the lengths to which the cables would need to be cut prior to the installation of the RCA connectors or spade lugs are closer to 57.2" than to 57 1/8". I do not know if this matters, but if 1/8" relative to the 57" matters, maybe the precise length matters as well.
Another discrepancy which may have more significance has to do with the lengths of Fulton speaker cables which were nominally 14 feet (three Fulton Lengths), 28 feet (six Fulton Lengths), 42 feet (nine Fulton Lengths), and 57 feet (twelve Fulton Lengths). What is particularly noteworthy is that none of the speaker cables that Fulton manufactured and sold were two Fulton Lenghs long, which is what is proclaimed in the above-referenced post as being the proper and presumably the best length.
 
Did some padding with nude manganin wire to get the right subjective listening impression. Earlier tried using nichrome and tungsten wires at the same location - nichrome was quite harsh which is found in 90% of the wire wound resistors. Tungsten was nice but little laid back. Manganin is the correct material for my setup - subjectively. Not made any measurements recently and only looking at tuning by ear method.

I have noticed off-late that there is not much co-relation between measurement, simulation and actual listening and hence trying to tune only by subjective listening.
 
Did some padding with nude manganin wire to get the right subjective listening impression. Earlier tried using nichrome and tungsten wires at the same location - nichrome was quite harsh which is found in 90% of the wire wound resistors. Tungsten was nice but little laid back. Manganin is the correct material for my setup - subjectively. Not made any measurements recently and only looking at tuning by ear method.

I have noticed off-late that there is not much co-relation between measurement, simulation and actual listening and hence trying to tune only by subjective listening.
Hello Hari,

Lets give HFV F.M.s a better background, with information on Manginin wire, so they may consider using it themselves beneficially in their own crossovers.

( I use it on my ALTEC VOTTs, to pad ALTEC 802D compression drivers, in lieu of any potentiometer, or any resistor. )

Here we go, a highly recommended and wonderful audiophile POST to learn from :



To source a supply, go look on eBay. Is not particularly costly. Here :



Enjoy your highs, I do !! ............... Hari seemingly now - also.

Jeff
 
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After almost 60 days of break-in of the new Russian Driver i measured the FR last weekend and this is what i get,
1656597711392.jpeg

The blue line is without the russian driver and the violet is all 3 drivers connected in parallel. If you notice the violet line, there is a dip in the response of the russian driver from 3Khz till around 6Khz after which the response begin to rise. This behaviour of the the FR dual cone is very common when the main cone and the whizzer cone are out of phase of each other in their relative displacement / movement. The only solution to this is to dampen the surround by adding more stiffness or somehow damp the main cone vibration so that the phase shift is minimum. Though i cannot make out anything from my listening, nevertheless the measurements are consistent in displaying this anomalies.

As there are no easy solution to this issue, the only option i could think of which was workable was replacing the Russian Driver with something else. I researched for a week and arrived at using a compression driver in its place. I have ordered a JBL Selenium D220TI CD and a Dayton Audio 8" round horn to fit in the same place of the Russian Driver. This will allow me minimum modifications to the baffle and can continue using the same baffle without any added cost. Due to the CD + Horn profile i am expecting a better directivity response in the off-axis listening position. The horn profile has a lower cut-off frequency of around 2200Hz and i may cross it around 5Khz for a -6dB response around 3KHz to match with my mid-range driver. The challenge will be to level match the two with a resistor network.

Thanks for looking.
 
I have received my JBL Selenium compression driver last weekend. Would be able to test them only next week after i receive my Dayton Audio horns. The reason for me to try this combination is,
- The Russian driver 10gdsh-1-4 has an overlap with the Sachenwerk field coil in the mid-range region. The 10gdsh-1-4 is a high compliance driver and the field coil is a low compliance driver. Both the drivers in the frequency overlap region has a mis-match in the cone motion when driven simultaneously due to difference in the cone and suspension stiffness. This will cause phase errors in the common frequency region due to destructive interference and there by causing compression and bright sounding mids. This problem cannot be eliminated by time alignment as its more of a speed issue.
- Adding a compression driver above 3KHz will not have this midrange overlap and both the field coil and the CD will work independent of each other.

Having said this - the 10gdsh-1-4 sounds very nice in the HF region (though it measures bad) and it will definitely challenge the JBL selenium to outperform that. But as FMs know that i am a measurement freak, if it doesn't measure as good as it sounds - i am uncomfortable. Hope the JBL can live to my expectations of both good measurement and good sonics. Keeping my fingers crossed.
 
I had the opportunity to connect the JBL selenium compression drivers to my existing open baffle frame this week. I had made a initial measurements to gauge its SPL vis-a-vis the other drivers in the frame. The Selenium in my Dayton Audio Horn roll-off at around 800Hz. But i need them only above 3KHz and they were almost 12dB more sensitive than my other drivers. Used a simple first order filter of having a resistor and a capacitor in series just to get down to listen them. Currently they are levelled by +/- 1dB with the rest of the FR.

1657684325075.jpeg

1657684345390.jpeg




1657684295050.jpeg

Will post measured results later when i am able to get a less ambient noise disturbance.


Thanks for looking.
 
The version 1 of the crossover is now completed and have started listening them. Some components are with Epcos fan/ motor capacitor and are under testing. Planning to replace them with vishay DC LINK CAPACITORS later.

FM @captrajesh is planning visit today afternoon for a listen and subjective evaluation. He is the first FM getting to review the new speakers. His subjective listening experience and inputs will matter for me. Though i have measured the speakers impedance and FR, i shall refrain from posting them until captrajesh post his subjective listening impressions.
 
I am dropping the idea of getting a Vishay DC link capacitor for the crossover as its a dry type metalized PP capacitor. What i am looking for is a lush, soft and smoother presentation of the mids and highs. This takes me back to motor run oil filled capacitors. Most CDs and horn combination use an oil based capacitor for soft presentation of the highs as per my research instead of dry type capacitors.
 
FM @captrajesh is planning visit today afternoon for a listen and subjective evaluation. He is the first FM getting to review the new speakers. His subjective listening experience and inputs will matter for me. Though i have measured the speakers impedance and FR, i shall refrain from posting them until captrajesh post his subjective listening impressions.
Oops! I'm being unwittingly put on the test bench. :)
I called on @Hari Iyer to audition his speakers. They're sounding very different from what they were during my last visit. They had an open sound as before but added to the sound are refined highs which are more pronounced than before.

He has changed speakers positioning and made it kind of diagonal across the length of the room.

Depending on where you sit, the speakers sound from mid centric to balanced to slightly bass heavy. Surprisingly, at this bass heavy position, vocals also sound fuller.

We played MP3 songs in his collection to FLAC files from my pendrive and lastly, LPs through his Thorens TT via passive preamp. The LP sound has trounced the digital music by quite a margin.

All in all, an evening well spent.
 
Past one month I was experimenting with various capacitors for my parallel crossover and had purchased various capacitor type - oil capacitors, Jantzen, Mundorf Evo - audiophile grade, Tibcon , DVM Gold, Lexus ( last 3 capacitors are AC capacitors - oil filled).

In the MPP type I was previous using Epcos and Havells capacitors. These were a bit harsh in sound. I replaced them with Tibcon Oil and DVM Gold - both were very nice, smooth, fatigue free with a little Air to my liking. Lexus was a bad oil type capacitor which I returned without hesitation.

The worst xapacitor I found was again Jantzen SQ wise. Comparing with Tibcon the Jantzen was harsh and fatigued. The best was Mundorf EVO - Audiophile, very similar or slightly better than DVM Gold Air conditioner Oil filled sapacitor. Very smooth an transparent.
I did some research on why Jantzen sounds bad, but could not find a single link to their specifications mentioning dissipation factor ( are they hiding something). Even Indian AC capacitor mentioned that dissipation factor as (0.001). The best was Mundorf Evo (0.0002). Dissipation factor in a capacitor is directly linked with noise, harshness and rough sound. I am scrapping all my Jantzen capacitors now.

After all the above experience, I was wondering that even the best capacitors have their own unique sound signature and it can be personal. You either like it or hate it. I went ahead and later designed a capacitor less crossover with just one inductor and one non- inductive resistor. This gave me the sound signature that I was looking for years and the one I was always tinkering with. I have ordered the final inductor and with that I shall be concluding with all my speakers tweaks. It took me close to 3 years to get this finally done.

Thanks for looking.
 
Hari,

Interesting thread and cool doings at your residence recently with audio. I think it is INTERESTING that Captrajesh and you thought that your analog L.P.s " killed" whatever digital source formats you guys played and heard on your system.

I also recall you HAD to use your Thorens phono, to more easily differentiate internal phase polarities, a few months ago.

I would venture to guess, the better your components are ( amp, wiring, speakers ) the less satisfied one becomes with digital play back.

When I listen to digital at home with my two-way ALTEC horn system, subliminally, I always feel that " something is wrong " with play back, with my own digital sources. :(

From what you and Captrajesh reported herein, I can understand now - why you were so receptive to building my favorite take-off, of Jim Hagerman's Cornet Phono Preamp.

Hari, I think, with these phono circuit changes we two plan to execute, this can become the penultimate phono preamp.

We will apply direct coupling, and special B+ treatment, for each and every triode's B+ feed. ( ALL Passive - Double SHUNTING, and double Dennis Fraker Final Filters ). This rather easily should be incomparable to anything, anyone in audio has ever done...or has ever even heard.

For a couple months now, my own 2021 HFV stereo DIY 6005 ( personal amp ) has been breaking in. This new 6005 amp design has taught me several things, .....good things. The amp's "resolution level" is WAY off the scale, it boggles my mind on each listening session. Totally scary !! Same can be said, .... for it's dynamic contrasting.

We will just apply a similar approach ( with a squeeky clean B+, and great Transfer Efficiency ), to every audio tube stage inside the new phono circuit.

Unfortunately, the remainder of 2022 will be spent on prototyping those 6005 " TRIPLE " mono blocks. That SE-TRIPLE circuit HAS to be built, listened to, and evaluated / enjoyed !!! My responsibility.

The all-out Phono build is for 2023. I have over 10,000, maybe 13,000 or so LPs, waiting ! I am weary, unhappy, and not-trusting of my digital listening.

I have not heard your amp's execution. ' Am curious, does Captrajesh ( or anyone ) ever give any notice at all, or offer a comment, RE : your own 2020 KT-88 power amp Hari?? Anyone have a clue yet ?

Jeff
 
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Hari,

Interesting thread and cool doings at your residence recently with audio. I think it is INTERESTING that Captrajesh and you thought that your analog L.P.s " killed" whatever digital source formats you guys played and heard on your system.

I also recall you HAD to use your Thorens phono, to more easily differentiate internal phase polarities, a few months ago.

I would venture to guess, the better your components are ( amp, wiring, speakers ) the less satisfied one becomes with digital play back.

When I listen to digital at home with my two-way ALTEC horn system, subliminally, I always feel that " something is wrong " with play back, with my own digital sources. :(

From what you and Captrajesh reported herein, I can understand now - why you were so receptive to building my favorite take-off, of Jim Hagerman's Cornet Phono Preamp.

Hari, I think, with these phono circuit changes we two plan to execute, this can become the penultimate phono preamp.

We will apply direct coupling, and special B+ treatment, for each and every triode's B+ feed. ( ALL Passive - Double SHUNTING, and double Dennis Fraker Final Filters ). This rather easily should be incomparable to anything, anyone in audio has ever done...or has ever even heard.

For a couple months now, my own 2021 HFV stereo DIY 6005 ( personal amp ) has been breaking in. This new 6005 amp design has taught me several things, .....good things. The amp's "resolution level" is WAY off the scale, it boggles my mind on each listening session. Totally scary !! Same can be said, .... for it's dynamic contrasting.

We will just apply a similar approach ( with a squeeky clean B+, and great Transfer Efficiency ), to every audio tube stage inside the new phono circuit.

Unfortunately, the remainder of 2022 will be spent on prototyping those 6005 " TRIPLE " mono blocks. That SE-TRIPLE circuit HAS to be built, listened to, and evaluated / enjoyed !!! My responsibility.

The all-out Phono build is for 2023. I have over 10,000, maybe 13,000 or so LPs, waiting ! I am weary, unhappy, and not-trusting of my digital listening.

I have not heard your amp's execution. ' Am curious, does Captrajesh ( or anyone ) ever give any notice at all, or offer a comment, RE : your own 2020 KT-88 power amp Hari?? Anyone have a clue yet ?

Jeff
Thanks Jeff, I shall postpone my tube phono presmplfier build for an year or so for one major reason. The phono preamp output is coupled to a tubed line preamplifier. You can connect your other line source also to this line preamplifier with a selector switch. In my xase 80% of my listening will be on my digital source. So I may waste tube power in my phono preamplifier just by turning them on. I want to avoid this as I am quite happy with my passive volume control for all my other sources.

@captrajesh listen to my previous avatar of my phono preamp which did not havexa class A output stage. Also my CD was just 3 days old when he came and after that I have completely modified my speaker design from parallel to series. Other than him no other hfv FM have visited yet.
 
Thanks Jeff, I shall postpone my tube phono presmplfier build for an year or so for one major reason. The phono preamp output is coupled to a tubed line preamplifier. You can connect your other line source also to this line preamplifier with a selector switch. In my xase 80% of my listening will be on my digital source. So I may waste tube power in my phono preamplifier just by turning them on. I want to avoid this as I am quite happy with my passive volume control for all my other sources.

@captrajesh listen to my previous avatar of my phono preamp which did not havexa class A output stage. Also my CD was just 3 days old when he came and after that I have completely modified my speaker design from parallel to series. Other than him no other hfv FM have visited yet.


The Phono stage schematic you received also has a superbly fed ( B+ design - wise) single 12B4 tube Line stage running hot at 33 mA. This can anode-drive with gain our usual 10K L-Pad ( constant impedance ) volume control.

You can hook up your digital sources either before or after the 12B4 tube stage .

A volume control, ( exactly the same as in your present all passive attenuator ), is the last part used - other than an RCA output jack. For signal switching, it will take a Grayhill brand all silver contact shorting ( Make Before Break ) switch, to do that well.

After 2019, hearing what double shunting in series, and two Dennis Fraker Final Filters in series did for a tube's B+ feed, ( subjectively - the quiet ultra - resolution - this provides ), it is hard for me NOT to include this new B+ topology in sensitive spots.

Why not apply such topology to a tube phono-line preamp??

I believe people in audio design, up until now, have grossly underestimated the importance and the sonic result !!! Only a few people have ever even heard this.

Jeff
 
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The Phono stage schematic you received also has a superbly fed ( B+ design - wise) single 12B4 tube Line stage running hot at 33 mA. This can anode-drive with gain our usual 10K L-Pad ( constant impedance ) volume control.

You can hook up your digital sources either before or after the 12B4 tube stage .

A volume control, ( exactly the same as in your present all passive attenuator ), is the last part used - other than an RCA output jack. For signal switching, it will take a Grayhill brand all silver contact shorting ( Make Before Break ) switch, to do that well.

After 2019, hearing what double shunting in series, and two Dennis Fraker Final Filters in series did for a tube's B+ feed, ( subjectively - the quiet ultra - resolution - this provides ), it is hard for me NOT to include this new B+ topology in sensitive spots.

Why not apply such topology to a tube phono-line preamp??

I believe people in audio design, up until now, have grossly underestimated the importance and the sonic result !!! Only a few people have ever even heard this.

Jeff
If I build this design it would be a passive for line stage and tubes only for phono. That way I don't have to turn the amplifier on for digital.
 
If I build this design it would be a passive for line stage and tubes only for phono. That way I don't have to turn the amplifier on for digital.

You cannot drive a 10K L-Pad Volume Control from the equivalent of 1/2 a 12AX7. ( Too high in Z. )

Build it 1/2 12AX7 Xs 2 and 12B4, with Grayhill silver switch and 10K L-Pad at the end. You would ONLY need to turn "ON" preamp's power if using phono, to activate all three tube stages. You keep the passive attenuator, at the end of the preamp, and it is NOT dependent upon activating the 12B4 stage when doing digital.

Jeff
 
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You cannot drive a 10K L-Pad Volume Control from the equivalent of 1/2 a 12AX7. ( Too high in Z. )

Build it 1/2 12AX7 Xs 2 and 12B4, with Grayhill silver switch and 10K L-Pad at the end. You would ONLY need to turn "ON" preamp's power if using phono, to activate all three tube stages. You keep the passive attenuator, at the end of the preamp, and it is NOT dependent upon activating the 12B4 stage when doing digital.

Jeff
One more very important reason for me to not consider a tube phono preamp would be my very small vinyl collection of around only 100 records. Doesn't make sense going over the board for such small collection. Moreover buying records currently over here is getting expensive by the day and has more nostalgia that Value for me for the amount spent. I would rather buyxa more expensive audio transformer for my digital source and make my digital source more robust. Moreover my current JFET input with class A discrete buffer based phono preamp sounds awesome to my ears and should be sufficient atleast for the time being.
 
One more very important reason for me to not consider a tube phono preamp would be my very small vinyl collection of around only 100 records. Doesn't make sense going over the board for such small collection. Moreover buying records currently over here is getting expensive by the day and has more nostalgia that Value for me for the amount spent. I would rather buyxa more expensive audio transformer for my digital source and make my digital source more robust. Moreover my current JFET input with class A discrete buffer based phono preamp sounds awesome to my ears and should be sufficient atleast for the time being.

OMG! That is the exact reason WHY you should consider a tube phone preamp. Your 100 records should be cherished like fine spices or wine! When people visit and they go to pick up one of those sterile metallic coasters you stop them and say "Wait!" You hand them the vinyl pressed genitally between the edges of your hands as their eyes widen! And you say.. "Let me play you something really special." As their senses begin to awaken from that long digital slumber they intriguingly look towards the clicking of switches and the glow of TUBES! As you cue the tone arm look back and say... "Are you ready" Yes! YES!
 
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