Salt Cellar Initiative

[mwhouston 4,888]

To get a grasp of where I’m am going with this thread you need to of read or have read  this article. 
 

https://www.stereophile.com/content/gramophone-dreams-34-salt-cellar-system

 

If you go no further at the least it is in interesting read. Some will go “meh” others will take it on board to search for better reproduction. Maybe even build there own SC. The challenge I have given myself and would like to throwout to others is can you build or hobble together a “Salt Cellar“ (SC) system. The core of a SC system is purity of sound, dynamics and immediacy. 
 

These are the constrains/opportunities I’m am pursuing;

 

• a monaural system
• high efficiency speakers - horns where possible
• a tube low power Class A mono power amp or even tube integrated amp
• vintage tubes
• mono vinyl phono playback from mono cart or mono wired phono stage 
• ultra short non shielded interconnects and speaker leads of Silver plated wire wrap wire

?

Ive been tossing this temp system around since I read that article and now have  (in my head) a whole SC system. So cutting to the chase I’m going to build a mono integrated wine box tube amp based on some vintage 807 and RCA 6SN7. Half the 6SN7 will be a single stage preamp and the other half the driver for a Suncalc designed 807 amp.

 

Speakers will be my Beyma 12” concentrics with a Altec 511B horn and FatalPro driver. The horns will handle mid-range and the tweeter in the horns super tweeters. Overall efficiency about 98db. 
 

Im current working three other projects but now taken on a forth for a true SC system. Any other takers out there. 

[sir sanders zingmore 11,988]

I shall follow this with interest!

[mwhouston 4,888]

9 minutes ago, sir sanders zingmore said:

I shall follow this with interest!

10% for the first twelve months, after tax. 

[mwhouston 4,888]

Here is the schematic for a stereo 807. I’m building the mono version with some well used Vintage tubes.  Also here is my build of the 807 designed by Suncalc on diyaudioprojects site. 
 

https://retro-thermionic.blogspot.com/2012/03/luciano-807-power-amp.html

 

[Mullet 40]

Very interesting.

[mwhouston 4,888]

I download the Fed McDowell music. Really couldnt see (or hear) any value in it. I have far better all analogue tracks which will pepper up the SC system. 

Edited June 14, 2020 by mwhouston

[davewantsmoore 6,501]

I like this.

 

1 hour ago, mwhouston said:

These are the constrains/opportunities I’m am pursuing .....

 

Quote

Griesinger's main requirements for improved clarity are: a) maintain a high ratio of direct to reflected sound, and b) preserve the phase (time) coherence of harmonics of (voice range) sound.

That is what you need to do to get the magic.

 

Source, doesn't matter....Electronics, doesn't matter.... as long as each are relatively well engineered.

 

Horn and open baffle (dipole) speakers both have a higher direct to reflected ratio than monopoles.    They are what you need for a) ... but it has to be very well designed to get b) too.    There are a lot of horn and dipole examples out there which have serious problems... and don't "do it".

 

Quote

can you build or hobble together a “Salt Cellar“ (SC) system

For home hifi SPL levels.......  Build a single big horn, and drive it with a ~2" cone driver .... crossover at about 300Hz to a large woofer.

 

1 hour ago, mwhouston said:

Altec 511B horn

I worry that the XO from this to the 12" will fall within the voice range.... and so you do not get b)

 

 

I have both a "PSE144" horn, and a 4 way dipole speaker (like a Linwitz LX521 / Nao Note) .... and they both do it .... although the PSE a little better.

It is the higher direct to reflected ratio which is the biggest part.    It is a huge jump in "clarity".

 

 

[mwhouston 4,888]

I doNt expect the 12” Beymas/horn combo to be the best it’s more about, as in the article, hobbling together a different base system and see what eventuates.
 

I chose the 807 because of its top cap and I wanted that Ye olde look. Not only that they are the choice of some serious tube lovers. Will on.y be a few watts but with 98db efficiency in the speakers there should be good volume. Not expect big bass but should be sufficient. The Beymas get down to 50hz with my other tube amps. 

 

 

[mwhouston 4,888]

I have Grade mono cartridge but I thought of this method to convert my stereo carts to mono. MM is to see 44K.

[davewantsmoore 6,501]

2 hours ago, mwhouston said:

I doNt expect the 12” Beymas/horn combo to be the best it’s more about, as in the article, hobbling together a different base system and see what eventuates.
 

I chose the 807 because of its top cap and I wanted that Ye olde look. Not only that they are the choice of some serious tube lovers. Will on.y be a few watts but with 98db efficiency in the speakers there should be good volume. Not expect big bass but should be sufficient. The Beymas get down to 50hz with my other tube amps. 

I think efficiency is only relevant when "you don't have enough".     What is "enough" is complicated.... but I think people chase it thinking it is responsible "for the magic", when it really isn't.

 

Directivity in the voice region is what they're talking about ..... keeping it suitably "narrow" (keeping in mind that almost all speakers are "very wide" in this region) ..... and keeping the phase correct (at all listening angles).

 

You will need to avoid "wide" in the 300 to 1200Hz region .... and avoid a change in directivity (or at least a sharp one).

[mwhouston 4,888]

I have all the parts I need to make the 807 triode Salt Cellar mono amp.  I think part of this project is to hobble together an amp cheaply and with parts on hand.  I have only had to shell out about $12 for some tube sockets Top cap for the 807. Everything else I had in de lab.

 

To keep cost down I’m making another wine box amp and are yet to drill and stain the box.  The big “Tranni” looking device is a Hammond  choke 10H 125mA. Tubes are all RCA 80 (rectifier), 6SN7 and 807.  An external universal Tranni box will supply 12VAC AND 250VAC. I think tube rectification is a must. The 80 is quite an old tube from the 1940s. 

[Lansche plasma guy 293]

Ideally with this sort of system speaker you really want a large and wide dispersion horn.  I did something similar many many years ago with a large multi cell altec horn and a altec a5 box.  Transformers and blended stereo to mono.  

 

Cant wait to read your progress.

 

LPG

[mwhouston 4,888]

13 minutes ago, Lansche plasma guy said:

Ideally with this sort of system speaker you really want a large and wide dispersion horn.  I did something similar many many years ago with a large multi cell altec horn and a altec a5 box.  Transformers and blended stereo to mono.  

 

Cant wait to read your progress.

 

LPG

It’s about what’s on hand. Luckily I have the Altec 511Bs and bass via the 12” Beymas. 

[mwhouston 4,888]

Before amassing parts for the dedicated SC integrated amp I thought I could just use one channel of one of the two 6L6 SE UL amps I already have. The speakers aren’t an Issue as I have two pairs of Altec 511Bs With FaitalPro compression drivers. One pair just doing nothing and the Beymas are in system two. Easy to put together and Xovers are already setup. 
 

I have a RCA setup which blends the two channels to one which I use for testing amp. After I have drilled and stained the new amp wine box I may just set this up for a listen. The 6L6 certainly looks the part though not triode. But it could be made triode. 

 

https://retro-thermionic.blogspot.com/2017/07/retro-6l6-se-ul-mkii-power-amp.html

 

 

 

 

 

 

 

[acg 2,647]

@mwhouston, I'm also interested to see where you end up with this effort.  I know someone that has heard the Slagle/Jackson ETF Salt Cellar system and apparently it was/is something special.  Big mono, horns, DHT amps, an old Garrard (if I remember correctly) TT with a bespoke cart and LR phono.  A wonderful use of old tech with new methods and components, some a century old, but still able to wow us.  Even disregarding the value of the drivers and horns, there is a tremendous amount of $$ invested in that 'simple' mono system, more than most of us have invested in our own systems.  Not that $$ = SQ of course.  I suggest that the reported SQ of the system is as much a result of the knowledge of the two guys that put it together as the precise components used, although they did build most of the components themselves.

 

I see you are not building a DHT amp using the ancient 50 mesh plates though...hehehe...I can't afford them either.

 

 

[mwhouston 4,888]

3 minutes ago, acg said:

@mwhouston, I'm also interested to see where you end up with this effort.  I know someone that has heard the Slagle/Jackson ETF Salt Cellar system and apparently it was/is something special.  Big mono, horns, DHT amps, an old Garrard (if I remember correctly) TT with a bespoke cart and LR phono.  A wonderful use of old tech with new methods and components, some a century old, but still able to wow us.  Even disregarding the value of the drivers and horns, there is a tremendous amount of $$ invested in that 'simple' mono system, more than most of us have invested in our own systems.  Not that $$ = SQ of course.  I suggest that the reported SQ of the system is as much a result of the knowledge of the two guys that put it together as the precise components used, although they did build most of the components themselves.

 

I see you are not building a DHT amp using the ancient 50 mesh plates though...hehehe...I can't afford them either.

 

 

The only thing I have built DHT is a preamp with century old tube.  Astonishingly good.  Drilled the wine box today hope to sand and stain tomorrow. 
 

http://retro-thermionic.blogspot.com/2020/04/mwh-1920s-ux-171a-tube-preamp.html

 

[acg 2,647]

Yes, saw that one when I had a look at your site earlier today.

 

I have a DHT midrange channel.  Can use 2.5V or 4V tubes such as 45, 2A3, RE604, YO186.  AC heating and dead silent with your head in the 112dB/w/m midrange horn.  Uses a Dave Slagle 80% mumetal output transformers.

 

Will soon build my own DHT preamp for kicks...71a, 45, YO186 and 801a will be tried.  VC will be Slagle autoformers.  If the pre ends up with output transformers no doubt they will be Slagle mumetal.  The integrated LCR phonostage has Slagle mumetal inductors and MC SUT's.  Could say I like his work... 

[mwhouston 4,888]

3 hours ago, acg said:

Yes, saw that one when I had a look at your site earlier today.

 

I have a DHT midrange channel.  Can use 2.5V or 4V tubes such as 45, 2A3, RE604, YO186.  AC heating and dead silent with your head in the 112dB/w/m midrange horn.  Uses a Dave Slagle 80% mumetal output transformers.

 

Will soon build my own DHT preamp for kicks...71a, 45, YO186 and 801a will be tried.  VC will be Slagle autoformers.  If the pre ends up with output transformers no doubt they will be Slagle mumetal.  The integrated LCR phonostage has Slagle mumetal inductors and MC SUT's.  Could say I like his work... 

where are the OPTs used. Got an image got a link? Could say? Would say!
 

Did you see my 1/3W 1920s 71A power amp in a 1940s pot stand.  Nickel core Hammond interstate trannies as input/drivers. 
 

https://retro-thermionic.blogspot.com/2013/03/intermezzo-1920-ux-171-power-amp.html

 

[acg 2,647]

Yes, I remember your 71a power amp.  Nice job!

 

 

Here are the Slagle OPT's.  They do not need to pass the full frequency range because a line level passive filter is included at the input to the amplifier thus restricting the amplifier output and enabling a direct connection from OPT to compression driver (no speaker level filter).  It works a charm.

 

 

 

Here is a photo of the midrange Slagle OPT against other OPT's used in the amplifier.  That Black Art bass output transformer is a beast made on 6" lams...look at it's specs...it takes full power from a 6c33c and directly drives a 1R speaker (subwoofer) load down to 6Hz.

 

 

 

A shot during construction...in the foreground you can see the bottom of the midrange horn the Slagle OPT in the background drives...

 

 

 

My system currently is a lot like your Salt Cellar system in that I use horns and triodes and due to a ridiculous workload have only (mostly) finished one side and am listening in mono.  Sounds freakin awesome though.

 

 

 

 

Edited June 22, 2020 by acg

[mwhouston 4,888]

47 minutes ago, acg said:

Yes, I remember your 71a power amp.  Nice job!

 

 

Here are the Slagle OPT's.  They do not need to pass the full frequency range because a line level passive filter is included at the input to the amplifier thus restricting the amplifier output and enabling a direct connection from OPT to compression driver (no speaker level filter).  It works a charm.

 

 

 

Here is a photo of the midrange Slagle OPT against other OPT's used in the amplifier.  That Black Art bass output transformer is a beast made on 6" lams...look at it's specs...it takes full power from a 6c33c and directly drives a 1R speaker (subwoofer) load down to 6Hz.

 

 

 

A shot during construction...in the foreground you can see the bottom of the midrange horn the Slagle OPT in the background drives...

 

 

 

My system currently is a lot like your Salt Cellar system in that I use horns and triodes and due to a ridiculous workload have only (mostly) finished one side and am listening in mono.  Sounds freakin awesome though.

 

 

 

 

Great work. What Is the tube compliment. 

[mwhouston 4,888]

In my 71A preamp and power amp the tubes have nickel plates. Also the input Tranni for the power amp has a nickel core. I’m wondering just how much nickel adds to the sound? Both are extremely engaging to listen to. 

[acg 2,647]

All Russian right now, and all wired in triode:

• Sub and Bass and Upperbass channels all 6e5p driving 6c33c-b (either one or both filaments)
• Fundamentals Channel 6e5p single stage triode
• Midrange 6e6p driving DHT (currently using YO186, have some 45's here to also try at some stage)
• HF 6e6p single stage

[acg 2,647]

3 minutes ago, mwhouston said:

In my 71A preamp and power amp the tubes have nickel plates. Also the input Tranni for the power amp has a nickel core. I’m wondering just how much nickel adds to the sound? Both are extremely engaging to listen to. 

 

If you listen to some, the more nickel in the transformer the better the sound and I tend to agree within limits.  There are varying amounts in use though, 40% nickel is relatively common but 80% nickel starts to get expensive and is easier to saturate.  It is also horses for courses.  I've used 80% nickel in the crucial midrange channel, amorphous Lundahl in the lower channels and some good steel lams for the subs where inductance rules because that seemed the best use cases for each.

 

In the phonostage and preamp it will be all Slagle 80% nickel right from the SUT's to inductors to output transformers and autoformers.  All that iron is sitting here on my desk as a reminder to get to the build. 

[mwhouston 4,888]

There are a number of pentodes and tetrodes etc. I could have used as the power tube. In all  cases I would.d have triode strapped them. I do know some tubes “triode” better than others.

 

Just a few tubes I have on hand (and not just pentode) and could of used are; KT88, EL34, 6V6, 6L6, 6EM7 (is a dual triode), 6T9 (triode and pentode) and a little metal fellow - the 12A6 (see link) - 

 

https://frank.pocnet.net/sheets/049/1/12A6.pdf

 

But staying with the Salt Cellar Initiative it must have a top cap. In de lab this was my only tube I knew I had both a cct. for and had a top cap. 
 

I have seen a schematic or two using a 12A6. Could be the next SC amp.    

 

 

Edited June 23, 2020 by mwhouston

[mwhouston 4,888]

A Salt Cellar/Steam Punk combo may be interesting. No I’m just making a plain SC amp. I may also make a SC mono MM tube phono stage. 
 

Edited June 24, 2020 by mwhouston

[mwhouston 4,888]

I wonder of there should be a Salt Cellar Lite for those with high blood pressure. A reduced Salt in the Cellar. What if a member wants do try a SC amp/speaker setup but can’t muster a setup with the points outlined early. We don’t want them having a heart attack over the project. A relaxing of some suggested guidelines may be in order.

 

A Salt Cellar Lite (low salt version) may just be;

 

• at least a tube power amp
• horn mid range
• and mono.

There is a SCL for those wanting to have a go but with restricted ability. 

 

 

Edited June 25, 2020 by mwhouston

[mwhouston 4,888]

Assembled not wired. Stained and lacquered and with a rustic up from the cellar look and an aged timber feel. Ive include a raw wine box ($9) to show the difference. . 
 

But the universal transformer pack I use with my Wine Box 6L6 amps can’t be used here with tube rectification. A new external Tranni will be assembled bread board style. 

[aussievintage 3,609]

On 14/06/2020 at 9:50 PM, mwhouston said:

1. a monaural system
2. high efficiency speakers - horns where possible
3. a tube low power Class A mono power amp or even tube integrated amp
4. vintage tubes
5. mono vinyl phono playback from mono cart or mono wired phono stage 
6. ultra short non shielded interconnects and speaker leads of Silver plated wire wrap wire

 

Just had a read of the thread, thanks for putting the note in the "what are you building" thread.

 

I am not sure I have absorbed exactly what it is all about yet, but it puts me in mind of the system I have run for many years in my record library room.     I have always really enjoyed the mono sound it produces, so I may have an inkling of what these salt cellar systems are about.

 

It is mono , so tick #1 on your list.  I use a 12" twin-cone Plessey Rola speaker, so quite efficient, but not a horn (except for the horn in the middle of it)  - so partly #2.  Noting Dave's comments, it IS mounted in an open back box (open baffle).

 

I usually power it with a mono 6L6 UL push-pull amp, but have many Class A SE amps I could use.  Probably would use one channel of a 6SN7/6L6 amp I have. - tick #3.

 

By vintage, I suspect you mean older than 6L6?   What if I use an old metal can 6L6, or old coke bottle 6V6 ?  At least it's all octal.   Part #4?

 

I use 2 turntables, a Garrard 4Hf with original tonearm for 78s, and a cutout for an SME3009 (that I can put back in a few minutes.) and a Garrard AT6 changer for stacking old mono 45s.  Mono wired stereo carts mostly, although I do have some mono crystal/ceramics.  Tick #5

 

Not sure why you want to do #6.  It almost doesn't seem to fit the feel of the rest of the stuff.

[mwhouston 4,888]

8 hours ago, aussievintage said:

 

Just had a read of the thread, thanks for putting the note in the "what are you building" thread.

 

I am not sure I have absorbed exactly what it is all about yet, but it puts me in mind of the system I have run for many years in my record library room.     I have always really enjoyed the mono sound it produces, so I may have an inkling of what these salt cellar systems are about.

 

It is mono , so tick #1 on your list.  I use a 12" twin-cone Plessey Rola speaker, so quite efficient, but not a horn (except for the horn in the middle of it)  - so partly #2.  Noting Dave's comments, it IS mounted in an open back box (open baffle).

 

I usually power it with a mono 6L6 UL push-pull amp, but have many Class A SE amps I could use.  Probably would use one channel of a 6SN7/6L6 amp I have. - tick #3.

 

By vintage, I suspect you mean older than 6L6?   What if I use an old metal can 6L6, or old coke bottle 6V6 ?  At least it's all octal.   Part #4?

 

I use 2 turntables, a Garrard 4Hf with original tonearm for 78s, and a cutout for an SME3009 (that I can put back in a few minutes.) and a Garrard AT6 changer for stacking old mono 45s.  Mono wired stereo carts mostly, although I do have some mono crystal/ceramics.  Tick #5

 

Not sure why you want to do #6.  It almost doesn't seem to fit the feel of the rest of the stuff.

Hey, glad you are taking this seriously. Love it.

#6 is an Allen Wright thing. Short, ultra fine non shielded interconnects and speakers wire. Wire warp wire from Jaycar is silver plated fine wire. Can be used for speaker wire in flea power amps in short lengths and as interconnects. Non of my interconnects in my main system are shielded and most made from wire wrap wire. 

 

[mwhouston 4,888]

9 hours ago, aussievintage said:

 

Just had a read of the thread, thanks for putting the note in the "what are you building" thread.

 

I am not sure I have absorbed exactly what it is all about yet, but it puts me in mind of the system I have run for many years in my record library room.     I have always really enjoyed the mono sound it produces, so I may have an inkling of what these salt cellar systems are about.

 

It is mono , so tick #1 on your list.  I use a 12" twin-cone Plessey Rola speaker, so quite efficient, but not a horn (except for the horn in the middle of it)  - so partly #2.  Noting Dave's comments, it IS mounted in an open back box (open baffle).

 

I usually power it with a mono 6L6 UL push-pull amp, but have many Class A SE amps I could use.  Probably would use one channel of a 6SN7/6L6 amp I have. - tick #3.

 

By vintage, I suspect you mean older than 6L6?   What if I use an old metal can 6L6, or old coke bottle 6V6 ?  At least it's all octal.   Part #4?

 

I use 2 turntables, a Garrard 4Hf with original tonearm for 78s, and a cutout for an SME3009 (that I can put back in a few minutes.) and a Garrard AT6 changer for stacking old mono 45s.  Mono wired stereo carts mostly, although I do have some mono crystal/ceramics.  Tick #5

 

Not sure why you want to do #6.  It almost doesn't seem to fit the feel of the rest of the stuff.

Big fan of the 6L6.

 

https://retro-thermionic.blogspot.com/2017/02/silver-supreme-6l6-se-ul-amp-in-wooden.html

 

https://retro-thermionic.blogspot.com/2017/07/retro-6l6-se-ul-mkii-power-amp.html
 

[mwhouston 4,888]

Good progress at least in the audio section of the amp. About  to start the PS section.  As usual with my builds it’s make it up as you go along - wiring that is. I’m working from a modified schematic and using half the 6SN7 as a preamp. This is an integrated amp.

[aussievintage 3,609]

1 hour ago, mwhouston said:

using half the 6SN7 as a preamp

 

Ever consider wiring the two halves in parallel?  I know people argue pros and cons, but I did it once to some 12AT7s and it worked nicely.

[mwhouston 4,888]

25 minutes ago, aussievintage said:

 

Ever consider wiring the two halves in parallel?  I know people argue pros and cons, but I did it once to some 12AT7s and it worked nicely.

I did but I want a true  integrated not a power amp with attenuator. I had the stereo version of the 807 and 6SN7 preamp seperate schematic. . I figured half 6SN7 preamp and half driver. The guy who design the 807 also design the preamp section. 
 

more progress, in-fact amp section is complete and started the rectifier/PS section.

[aussievintage 3,609]

1 minute ago, mwhouston said:

I figured half 6SN7 preamp and half driver.

OK, I didn't understand before.  I see now.

[mwhouston 4,888]

7 minutes ago, aussievintage said:

OK, I didn't understand before.  I see now.

But I did consider parallel operation. Also I placed the pot after the preamp stage so I’m not  throwing away raw signal. Preamping the lot then taking what’s needed for a comfortable listening level. 
 

All parts (or 90%) were what’s on hand which is one of the Salt Cellar guides. With a result there is very mixed compliment of values, in some areas, are ball park and not absolute. Also a mix of carbon 1W and metal 1/2W resistors, metal film and PIO caps. 

[mwhouston 4,888]

Most of the filtering (not with choke yet) done and some heater wiring. First cap in the PS is a Mundorf M-cap poly. 

[mwhouston 4,888]

Of the five big HT tube trannies I have none will produce the 300V I need for this SC amp. My hope was to use one of these big trannies as part of the hobbled together SC mono tube amp. They would have left me at least 40V short. In operation you may not have noticed the difference but for the sake of $200 I can get a healthy 300V which should push the amp to deliver its full brutal 2W. Tranni is ordered. Now the wait.

 

I have two other projects in line at the mo. so I’ll push on with those until the Tranni arrives. I have a matching Tranni board ready to go for when it does arrives. Still annoyed I had to layout to get this project done but I’m sure the extra time and cost will be worth it. At least I won’t die wondering. 

Edited July 7, 2020 by mwhouston

[mwhouston 4,888]

Here is the matching plinth for the power Tranni which will sit naked on the brd. I put in a inline power switch to keep with the old world feel. Not only that easier to install than a switch on the board. Fuse is incorporated.

 

A 12 way multi-pin connection is on the amp three umbilical cords to connect to the Tranni secondaries. Still waiting the Tranni.

[mwhouston 4,888]

The big ass Tranni arrived. Nearly finished another external PSs for preamps and phono tube amps. Once done (hopefully today) I’ll finish off the external Tranni brd. Then I can test the amp and setup my SC system. 

[allthumbs 1,007]

23 hours ago, mwhouston said:

Once done (hopefully today) I’ll finish off the external Tranni brd. Then I can test the amp and setup my SC system. 

Well?😃