AudioNervosa

Systemic Development => Amplification and Preamplification => Tubes => Topic started by: dBe on September 15, 2017, 09:41:20 PM

Title: Steve, great post!
Post by: dBe on September 15, 2017, 09:41:20 PM
http://www.audiocircle.com/index.php?topic=152696.msg1632139#msg1632139

Nice.
Title: Re: Steve, great post!
Post by: steve on October 14, 2017, 08:29:14 PM
http://www.audiocircle.com/index.php?topic=152696.msg1632139#msg1632139

Nice.

Thanks dBe. Much appreciated. Hopefully, my information will help some.

I have to wonder at all the upgrades, new models that come out year after year. Why, if they have optimized their designs long ago? 

How many advertisers claim they artificially flavor their design(s) for listener's tastes? I have not seen one yet. They all sound different, so which one designs and tests properly and which does not?

Of course cosmetics is a consideration.

Cheers

Steve

ps. I am thinking about either selling my designs, or manufacturing a 10A line preamplifier again. Probably very limited production if it does occur.
Title: Re: Steve, great post!
Post by: P.I. on October 18, 2017, 11:58:45 AM
One of the myths of audio, especially audio is "the latest and greatest".  I learned long ago that the "this years new, great piece" was last years piece with a cheaper mode of manufacture sporting the whiz-bang trendy cosmetics that go along with a higher retail price.

I am a nuts and bolts kind of guy.  That is why I gravitate to tube gear or really smart, lees is more SS designs by people like Nelson Pass.    Not to mention that fewerr devices don't screw with the signal nearly as much.

Same goes for speaker design.  Years ago I got in a LOOOOOOONG discussion with one of the "gurus" on another site about design philosophy.  His idea was to get everything flat using conjugate networks needed to use pound a driver with passband peaks and spikes that were just stupid big in amplitude.  My approach was to use drivers with out of passband responses that were smooth a couple of octaves out of the passband, align acoustic centers and use something like a second order L/R crossover.  The only netweorks that I would use were zobels or purely resistive impedance compensation to make the speaker easy to drive.  Certainly my designs might not have been ruler flat from DC to light, but they don't sound constipated in the way only too many components can do.

I really do think that a good preamp opens the window to great sound.  Think hard and let us know.  There is always room for excellence.   :thumb:
Title: Re: Steve, great post!
Post by: steve on January 11, 2018, 04:27:07 PM
One of the myths of audio, especially audio is "the latest and greatest".  I learned long ago that the "this years new, great piece" was last years piece with a cheaper mode of manufacture sporting the whiz-bang trendy cosmetics that go along with a higher retail price.

I am a nuts and bolts kind of guy.  That is why I gravitate to tube gear or really smart, lees is more SS designs by people like Nelson Pass.    Not to mention that fewerr devices don't screw with the signal nearly as much.

Same goes for speaker design.  Years ago I got in a LOOOOOOONG discussion with one of the "gurus" on another site about design philosophy.  His idea was to get everything flat using conjugate networks needed to use pound a driver with passband peaks and spikes that were just stupid big in amplitude.  My approach was to use drivers with out of passband responses that were smooth a couple of octaves out of the passband, align acoustic centers and use something like a second order L/R crossover.  The only netweorks that I would use were zobels or purely resistive impedance compensation to make the speaker easy to drive.  Certainly my designs might not have been ruler flat from DC to light, but they don't sound constipated in the way only too many components can do.

I really do think that a good preamp opens the window to great sound.  Think hard and let us know.  There is always room for excellence.   :thumb:

A couple of things that have really helped me; first was to design a perfect preamplifier that does not affect the signal in any way. The second was to design an amplifier with the same perfection. Both via listening tests; requires special setups, and lots and lots of time to get it right.

Once that is done, then I started on my 2 way test speaker. Been 4 years designing and tweaking the xover. One problem I have noticed is that crossing over two low with the full range driver causes problems using a 12db xover. So I had to raise the xover some. That has been basically finished, and the final tweaking is just done.

The woofer required an ~4.5 cubic foot box, large but I wanted to use an old fashioned driver with Qt of 0,7. The pressure on the cabinet walls is not so great, but it is 40 x 22 x 11. A couple of tweaks here and there and all finished, except for covering. Weighs ~80lbs.

cheers

steve

ps. Been 7 years with the test speaker and finally finished a few weeks ago. I do have a couple of adjustments on the speaker's back if I wish to tweak just slightly.
Title: Re: Steve, great post!
Post by: richidoo on January 11, 2018, 05:20:08 PM
Glad to know you're still developing new audio toys, steve. I hope you'll share them with us when you're finished?  :drool:
Title: Re: Steve, great post!
Post by: tmazz on January 12, 2018, 05:28:18 AM
Glad to know you're still developing new audio toys, steve.

Of course he is. Once you have been infected, the sickness never leaves.  :lol:
Title: Re: Steve, great post!
Post by: dBe on January 13, 2018, 06:55:59 PM
Cool.

I would be very interested to know which full range you are using.
Title: Re: Steve, great post!
Post by: steve on February 08, 2018, 10:30:29 PM
Several considerations. The first is how far off most audio components are in sound quality. It is amazing how good an "average speaker" sounds when matched to really accurate components. I think you guys have found the same thing. Second, got the room pretty flat.

Actually I have not liked any full range drivers over the years. However, ~4 yrs ago, Bill, a Rhode Island audiophile, who comes every fall to visit his parents grave site, brought a pair of 4.5" full range drivers (in small speaker boxes) with him and wanted me to audition them.

Well, I had Phast Jr. from Selah Audio (got good by on them), and they sounded better than most speakers individuals have brought over, and I could tweak them a little. Anyway, the Phast Jr. use a morel 2.5"? dome for the mids. Finally tried the FR drivers and darn if they didn't trounce the morels. Even subbed them for the Morels. Oh, I did do a little tweak to eliminate the beaming of highs.

There was some promise.

That got the ball rolling; started designing a test speaker. Something I wanted to try was to crossover at 200hz or less, 2 way. That substantially reduced the requirements of the woofer. I was sick of 45-50hz f3 response, wanted 30hz and reproduction to 20hz.

Forgot, it has been ~45 years since I designed a speaker, and I had no idea of how the project would turn out, so I didn't want to spend a lot of time. But then I have auditioned 28k speakers here and did not like them because they used an inaccurate audio system, and probably room to design them.

So I looked for a 12" woofer with a Qts of ~0.7. The woofer needed a 4.5 ft3 box; I reinforced it and installed the drivers. Internally dampened it with fiberglass.

The hardest part by far was the xover, and matching the woofer to the FR driver. That is what has taken over 4 years to get right. Besides adjustments of 1 part in some 300,000 (resistor tweak) making a sonic difference (change equivalent to frequency response change -105-110db down), even moving the speakers 1/32" rotating, sideways, height makes an amazing sonic difference. Of course temperature also a consideration.

Bought 500 watt inductors, matched to within one turn. Speakers only rated for 50 watts peak or so, using less than 20 watt peaks. Capacitors are matched (Tektronix meter) to read exactly the same capacitance in each channel.

Three controls in back of each speaker. One matches the woofer to FR driver, the second adjusts the Zobel, third is a switch that tweaks the woofer damping. Zobel caps are extremely critical in sonic quality, and uf size. I am using five foot length of 10 parallel 18 gauge solid wires from monoblocks to speakers. 8 or 12 in parallel do not sound as good.

I have auditioned the Harbeth L3/5a, a host of other speakers, heard about Fulton's, but I am finally happy with these albatross speakers. Can't even get them out of my apartment and down the stairs with a dolly though.

Frankly, they are a pain in the butt, so glad I am finished. But I sure do like hearing what I am hearing, all aspects.

The FR is -3db at 30hz and -13db at 19-20hz. Top measures to 20khz, but my hearing won't go that high anymore.

Got the flu now, gotta go.

cheers

steve
Title: Re: Steve, great post!
Post by: dBe on February 10, 2018, 08:54:32 PM
Steve,  your journey speaks to me in volumes.

In 1964 the lead guitar player in the band I was in and I started on a journey or two. His dad was a nuclear physicist at Sandia National Labs whose hobby was music appreciation.  We went to many live performances and spent time talking about all kinds of music.  He loved Mahler AND Chuck Berry.  Truly a renaissance man.  Built his own Klipschorn clones and the loudest guitar amp I ever heard for his son, my friend.  One of the takeaways from that journey were the 12" Norelco alnico twin cone fullranges used in Chuck's amp.  Blew up a bunch, but I got some to use with my Heathkit and later Dyna amps.  They were far from perfect with limited bass and somewhat ragged highs, but they imbued in me a magic that was lost in the years and speakers that came later. The coherency, the 'oneness' of the music was magical on vocals, acoustic instruments, jazz and in portraying the space in music.

Fast forward 50 years and here I am again in quest of that rightness that I remember. 

I've built 2-ways, 3-ways and even 4 ways trying to get that back. 

I'll say this:  the coherency that comes from a single, wide range driver bests (I almost said "Trumps") a lot of the temporary gratification of other alignments.  I can live with less than "perfectly flat" because every speaker that I have heard that got there was constipated in presentation (phase issues) or totally without the "emotional aspect" that comes with transient true and with proper ring out and release that comes with true point sources.

I'm past 115 dB listening sessions or the wowie zowie presentation that some speakers bring.
I do long for the effortless, musical immediacy that alnico drivers bring to the party.  With that, some of the new neodymium drivers do split the difference between the sweetness of alnico and the bigger than life presentation that ceramics give.

Hardest thing is getting the bottom end right.  So far either compound transmission lines or GR Research open baffle subs are the only things that do "it" for me.

YMMV, but good music is good music to the beholder, eh...
Title: Re: Steve, great post!
Post by: steve on February 10, 2018, 10:51:52 PM
I can appreciate your work dbe and sacrifice, both in efforts and time.

As you, I really want coherency and always found xovers in the midrange, even upper midrange to be detrimental. So I designed my xover for less than 200hz. Tweaking the xover in this area does not offend the midrange voices, maybe just slightly, while giving the coherency of all the harmonics I wanted, as the frequency increased. Crossing over where the ear is most sensitive is something I wanted to avoid. I personally would also not use a 12" FR or coaxial/tri driver. Much too ragged.

I found my woofer/room works nicely, and I use the woofer pointing inside, away from the wall, setup. (Sealed bass enclosure to allow for response at 20hz.) This allows me to adjust for a flatter in room bass response. The switch allows me to also adjust the damping at resonance. I can tweak the response from low up to the xover frequency. I can have nice taught deep bass or loosen it slightly at resonance for a little more umph.

The inside firing woofer also allows me to keep the front foot print down to 11" wide.

Frankly, I had no idea of how my finished project would sound when I started. What would be the limits? Another friend, Dan, has been up many times, was taught by a gent who retired from ARC, how to setup speakers. We did have times where we took a step or two back. So many variables, placement, xover tweaking. But we managed to keep going.

All I can say is, I am absolutely flabbergasted at how good my system sounds. Words cannot express my satisfaction. But then thousands and thousands of hours, over the decades to get each part of the system optimized/accurate. If I had a wish, more woofers to flatten the response to 20hz or below. But there would be no room for such. Oh, I can still tweak the controls to adjust if I feel the need.
But finally, basically, finished with no desire for anything else.

One other thing. I too, found how different magnet types affected the sound of drivers. Same drivers, same cones, supposively same gauss, but different magnet.  I also found the neo magnet version had a higher amplitude resonance that the ceramic magnet type. Interesting finding indeed. Maybe slightly different specs manufacturer didn't wish to publish.

Cheers

steve



Title: Re: Steve, great post!
Post by: dBe on February 10, 2018, 11:09:41 PM
Steve, there was never a sacrifice in loved in my quest.  It was all counted as joy as I learned so much along the way.  Uhm... Not quite true:  there was the occasional stupid injury along the way. Thank God I still have all my fingers, both eyes and most of my hearing.

I was very close to THE SYSTEM a few years ago, but I was talked into selling it.  What a dumbass moved for something as temporal as money.

I'm still on the ultimate quest where enjoyment surpasses every other aspect of audiophilia nervosa.  I'm getting there and will reveal all when and if that happens.

I envy you in a good way.

Keep on keepin' on... It is ALL about the music.
Title: Re: Steve, great post!
Post by: steve on February 11, 2018, 07:06:29 PM
Steve, there was never a sacrifice in loved in my quest.  It was all counted as joy as I learned so much along the way.  Uhm... Not quite true:  there was the occasional stupid injury along the way. Thank God I still have all my fingers, both eyes and most of my hearing.

I was very close to THE SYSTEM a few years ago, but I was talked into selling it.  What a dumbass moved for something as temporal as money.

I'm still on the ultimate quest where enjoyment surpasses every other aspect of audiophilia nervosa.  I'm getting there and will reveal all when and if that happens.

I envy you in a good way.

Keep on keepin' on... It is ALL about the music.

Thank you for the compliments Dave. I am really blessed in this field, but I keep in remembrance that everyone has their field(s) of expertise as well, just different "forums" is all.

I applaud you for your quest for your excelling system instead of just settling. Is it possible to obtain new components again, or were yours upgraded, or cost prohibitive?

Cheers

steve
Title: Re: Steve, great post!
Post by: dBe on February 11, 2018, 09:02:32 PM
Steve, there was never a sacrifice in loved in my quest.  It was all counted as joy as I learned so much along the way.  Uhm... Not quite true:  there was the occasional stupid injury along the way. Thank God I still have all my fingers, both eyes and most of my hearing.

I was very close to THE SYSTEM a few years ago, but I was talked into selling it.  What a dumbass moved for something as temporal as money.

I'm still on the ultimate quest where enjoyment surpasses every other aspect of audiophilia nervosa.  I'm getting there and will reveal all when and if that happens.

I envy you in a good way.

Keep on keepin' on... It is ALL about the music.

Thank you for the compliments Dave. I am really blessed in this field, but I keep in remembrance that everyone has their field(s) of expertise as well, just different "forums" is all.

I applaud you for your quest for your excelling system instead of just settling. Is it possible to obtain new components again, or were yours upgraded, or cost prohibitive?

Cheers

steve
The main components in that system were Cary 572SE MkII mono locks along with a minimalist Cary preamp, theSLP50B.  They were all massively modified in the power supplies as well as some wise choices in tube selections.  Speakers were my own skullduggery.  I worked on that combo for a long time tweaking weaknesses in every thing into strengths.  My big deal is synergism.  It's like an embrace:all of the parts have to fit.

The 572 tubes had a reputation for self destruction, but we're really amazing when they were well treated by their surrounding components.  A small change in plate resistor made all of the difference in both reliability and sweetness.

I'm turning to higher sensitivity, lower power and tidier systems.  Must be the age thing  :thumb:
Title: Re: Steve, great post!
Post by: tmazz on February 11, 2018, 09:25:25 PM


I'm turning to higher sensitivity, lower power and tidier systems.  Must be the age thing  :thumb:


.... and lighter.  8)   I don't know about you guys, but my days of humping around 168 lb Thieil speakers and 130 lb ARC amps are pretty much over. Those duties have now been relegated to my sons. (I knew they were good for something.  :lol:)
Title: Re: Steve, great post!
Post by: Nick B on February 12, 2018, 07:39:08 AM


I'm turning to higher sensitivity, lower power and tidier systems.  Must be the age thing  :thumb:


.... and lighter.  8)   I don't know about you guys, but my days of humping around 168 lb Thieil speakers and 130 lb ARC amps are pretty much over. Those duties have now been relegated to my sons. (I knew they were good for something.  :lol:)

+1 on the lighter weights. Heck, I was griping about about 65 lb speakers and a 65 lb amp. Then there’s the 80 lb turntable.
Title: Re: Steve, great post!
Post by: Brap on February 12, 2018, 09:45:42 AM
Dread the day I have to move my 1950's Jensen Imperial which is on the 2nd floor. Mahogany is heavy stuff
Title: Re: Steve, great post!
Post by: steve on February 12, 2018, 10:45:10 AM
I hear you all. My speakers are ~80lbs, can't get them down from the 2nd floor either. Luckily the monoblocks are only 25lbs or so each, 11A is 15lbs (NO chokes used! See my White Papers http://www.sasaudiolabs.com/sasaudio.htm ).

Dbe, good luck on your newer venture of smaller etc. At least you'll be able to carry the equipment to someone who can update those, if that is necessary.

Nick, yikes 80lb TT. Anyone know a good hernia doc?  :rofl:

cheers

steve
Title: Re: Steve, great post!
Post by: tmazz on February 28, 2018, 08:56:12 AM
(https://i.pinimg.com/564x/9f/86/9d/9f869d0fbdea493d44cdeb35c0c4deb6--betty-davis-old-age.jpg)
Title: Re: Steve, great post!
Post by: rollo on February 28, 2018, 11:03:37 AM
  I have learned over the years that simple not simpler is better. Once I decided that sound stage scale was not  one ofmy most important criteria my system has evolved to single driver 102db efficient speakers with built in sub to 18HZ.
  This allows me more choices in amplification from flea Watt to Mega Watt. I agree that an active preamp is key as it is the heart of the system. However lately some integrated designs have altered by view.
  Nelson Pass's research of Lowther type drivers has gone against common acceptance that voltage rather than current best suits that driver type. Hence the First Watt F7.
  No engineer here just ears incorporated. To my ears he may just be correct. Then I put in a Lamm SET ML2 [ 32W] and now rethink everything.
   Who is right who is wrong ? Let your ears determine that.


charles
Title: Re: Steve, great post!
Post by: steve on March 27, 2018, 03:57:10 PM
  I have learned over the years that simple not simpler is better. Once I decided that sound stage scale was not  one ofmy most important criteria my system has evolved to single driver 102db efficient speakers with built in sub to 18HZ.
  This allows me more choices in amplification from flea Watt to Mega Watt. I agree that an active preamp is key as it is the heart of the system. However lately some integrated designs have altered by view.
  Nelson Pass's research of Lowther type drivers has gone against common acceptance that voltage rather than current best suits that driver type. Hence the First Watt F7.
  No engineer here just ears incorporated. To my ears he may just be correct. Then I put in a Lamm SET ML2 [ 32W] and now rethink everything.
   Who is right who is wrong ? Let your ears determine that.

charles

I think I understand, especially with so many different brands, designs, and advertising. How does one find the best for them without auditioning so many components/systems. I have to admit I really feel for the public since all manufacrturers claim the best. But which ones fulfills the desires of each individual. How do we each arrive at that position.

I just heard some expressions, that some like all the instruments to blend together, such as in a live audience hall. Another expresses he wishes to "see" around each instrument and voice. If the instrument to appear brighter, while another likes fuller. Some like the inner detail of the studio/venue to shine through, while another likes it to sound as if the instruments are in the room, so not so much actual inner detail in the recording venue.

I, like you, have heard the phrase, simple but not too simple. To me, I think it means a system needs to be as simple as possible, but if made simpler than one desires, starts to lose quality, or options, that one wishes.

I agree the preamplifier is most important since it has to handle so many sources, and handles the lowest signal levels (except the phono stage) Rectification effects of different contact materials affect the signal quality more than at higher signal levels.

As far as amplifiers, I have somewhat of an advantage in that I can run special listening tests to obtain output the same as input. So then I just need to work on my test speakers (4+ years now) to satisfy my sonic desires, which I am very close. Of course there can be compromises, like 86-87db/watt sensitivity, but the rest of my goals are met.

Some day I would like to design a transformerless head phone amplifier using small signal tubes. If nothing else, just to see how it turns out.

Kind of ranting on,,, about it for now.

steve
Title: Re: Steve, great post!
Post by: P.I. on March 31, 2018, 05:51:11 PM
Yep, I'm with you, Steve.  I very much am in the simple is better camp, but first simple has to do the job it is intended to do. There is a point in design processes that we come to - does it that sounds great, but with them caveat of... is it the best it can sound or what if I can improve it with 'X'?  If the "what if" doesn't sound better then the last iteration is the best.  Simple designs need to be revisited when superior components become available, just to see (hear) what they may bring to the table.

I'll 'fess up.  I'm a triode gain stage into an SET kind of guy.  Gotta be the "right" components, though. m I've had more than enough hyper detail to last me 3 lifetimes.

Title: Re: Steve, great post!
Post by: steve on April 29, 2018, 05:49:00 PM
Yep, I'm with you, Steve.  I very much am in the simple is better camp, but first simple has to do the job it is intended to do. There is a point in design processes that we come to - does it that sounds great, but with them caveat of... is it the best it can sound or what if I can improve it with 'X'?  If the "what if" doesn't sound better then the last iteration is the best.  Simple designs need to be revisited when superior components become available, just to see (hear) what they may bring to the table.

I'll 'fess up.  I'm a triode gain stage into an SET kind of guy.  Gotta be the "right" components, though. m I've had more than enough hyper detail to last me 3 lifetimes.

I stumbled on to a venue that causes the FR to be really good down to the deepest bass. I think a description might be helpful to those who wish to build a room mostly devoid of deep bass resonances. Not perfect, but I think pretty good. Paneling all around inside the apartment.

My actual listening room has a weak wall, not much there, then a bedroom/concrete/wall/outside. The other side has a concrete wall, then hallway. Behind the speakers, the wall is concrete block with outside beyond. The opposite end also has a block concrete wall. Remember, paneling on all inside walls. Below my carpeted floor is a long garage which is also below the other apartment. Above my ceiling tile is an A frame roof. The concrete blocks do not go above the ceiling tile, so the A frame is rather large.

With this physicality, the upper bass, mids, highs "see" typical walls and reflections. However, the mid to low bass sees three concrete block walls of the room, then adjacent room (with concrete wall/outside). The ceiling sees an A frame space. The bass passes through the floor to the long garage. The losses appear to be just about right to not only lower any resonant frequency, but also absorb some of the energy. The bass seems pretty flat with no "one note boom".

It is interesting that if I open the bathroom door, the bass lessens noticeably. Closing the simple door is enough to increase the bass, but not any boominess.

If I understand you correctly, I think we agree that the electronics can make or break a system almost, or even just as much as a speaker. I found, through special listening tests, that electronics can be as far off as speakers, from specialized listening tests, just as much as speakers.

cheers

steve
Title: Re: Steve, great post!
Post by: steve on April 29, 2019, 10:14:43 PM
Hi All,

One year from my last post. It has been a year of still more improvements that I thought simply were not possible. As mentioned above, the interconnect cables, preamplifier, amplifier have been set. Sources are my modified NAD 521, Modi 2, and computer.

My 10A and 11A preamplifiers have been around for decades. The amplifier I use now has been the culmination of 40 years of research.

First, I started with SET designs.

Then I designed an OTL amplifier rated at 200 watts output in triode mode. Bandwidth was 1,2 mhz at ~ -3db. Harmonic distortion was .7% or less at maximum power output.

What was interesting was that I was able to get the push pull amplifier to sound more accurate and natural than my OTL amp or SET amplifier. One huge problem with the OTL amplifier (actual monoblocks) waw it drew 850 total watts just idling. The output tube's filaments drew 250 watts. Needless to say, I did not need a furnace in the winter time. Forget the summer time.

The last amplifier was the push pull amp using KT88s. I was able to obtain the near perfect accuracy, naturalness, imo better than either the SET or OTL. That was finished years ago.

This past year, I have been able to improve the speakers even more than I ever thought possible. I am now crossing over at approximately 170 hz. I have been able to rid of the zobel network. Although using modest drivers, individuals have been amazed with the lifelike accuracy, reproduction of bass kick drums, as well as just about any program material. To me, there is just a difference between large boxes and "subwoofers". The speakers cost less than $500.00 in parts. Labor, well that is another story. All that is left is to cover the cabinets.

What started out as tinkering around has turned into something I never thought possible in my wildest dreams.

I have auditioned some very good systems. They include Altec 19s, Hales Revelator 3s, Luxman mono, ST-70s, LS3/5As, Harbeths, Von Schweikert Unifields, Anniversary 5s, and systems at audio shows etc etc.

I have had some visitors, Dan, Steve, Steve, Bernie etc etc and at least two are bringing over their entire, expensive audio systems to compare to mine this week. A lot of work, but that is how excited they are. This should be a very interesting week indeed.

By the way, I replaced the polyester capacitors, and modified the power supply in the Modi 2.

I am basically finished, except I do have two controls on my speakers, in which I can still tweak if need be.
 
Cheers

steve
Title: Re: Steve, great post!
Post by: steve on July 14, 2019, 09:03:59 PM
Another update concerning my system improvements etc.

First, one of the gents had to have a hernia operation, so he could only bring his $4,000.00
Lampizator DAC. He loved the system with the Lampizator, so the Modi 2 needed some
more modding. Such has been done, and is much improved.

Besides the power supply caps being replaced (one is not polypropylene), and output
capacitors (originals are polyester/mylar) to polypropylene, I replaced the stock jacks
with Vampire all copper jacks. All three made a substantial improvement. Near world class dac.

Dan came up and loved my system. We are now looking for an output capacitor
since the one's I am using have not been available for some time. Looking at two brands that
could be promising to modify his possible Modi 2 as well.

So the weakness in my system was the source. The computer, NAD 521bee with analog section
bypassed still doesn't make it. But the modi 2 is really beginning to sound world class.

Maybe I will get more into the NAD and see what else can be done there.

cheers
steve
Title: Re: Steve, great post!
Post by: rollo on July 17, 2019, 09:22:37 AM
  Source, let me help. Innuos Zenith mk3 server. Aqua La Scala tubed [12AT ] DAC. 


charles
Title: Re: Steve, great post!
Post by: steve on July 18, 2019, 08:12:36 PM
  Source, let me help. Innuos Zenith mk3 server. Aqua La Scala tubed [12AT ] DAC. 


charles

Since my last post, I made one more tweak, and the Modi 2, in E position, is now world class,
simply amazing. I agree, the standard Modi 2 is crap, but the costs were kept way down.
I inspected the photos of the Aqua and frankly, I am not interested in the tubes (almost as
low of current as a 12AX7 types), and I am not familiar with the quality nor ufd values of
their capacitors. I have also been able to audition the $4k Lampizator and found the Modi 2
to be close, but that was before my last tweak. I would rather stick with what I either design
or modify. So far, ~$600 vs $6,000.

Dan has auditioned my modified Modi 2 and he is amazed as well, and thinking of making it
his reference. Problem is the caps I use have not been available for some time. So we are
checking capacitors to ascertain if there are any that meet my high sonic standards.
So far, none, but I have a few yet to test.

Dan is running two systems, with LS3/5A, and Harbeth speakers, Pro Musica modified
Luxmans with 8045 output tubes, modified AR SP3 preamplifier, can't remember the other pre etc.
He has been around for decades, so has a lot of experience with what is out there.
Of course, below is a list of my own lab designed, and special listening tested, components that
I use to enjoy. I can also test sources for sonic accuracy as well.

Cheers
steve