Synergistic Red Fuse ...

I felt I had a duty to report after reading 29 pages of postings. The naysayers are not helpful. Tweaks are system dependent. Higher end systems will generally be the most sensitive to changes. I chose to make the changes which give me the biggest bang for the buck. Also I designed parts of my listening environment so that I don't need some tweaks. I.e. Speaker wire lifters since my wires run under the 6" thick slab in a 11/2" pipe.

I am presenting my favorite tweaks to my mature Audio system.   The first is two pair of Shakti Hallographs.  They are essential to my large 7 driver box speakers.  I eliminated all of my sound absorption and deflecting panels when I set up the Hallographs.  The sound improved tremendously so that I am not contemplating replacing my speakers (combined with SR black fuse effect).  

As to the Shakti stones, they did not work in my audio system. Ben Piazza and Robert have attested to their effectiveness on my equipment. They may work well on other equipment

Secondarily,. Stillpoints are essential under my preamp which is built into a thin metal case with rubber feet.  Robert knows how honky it sounded pre Stillpoint Ultra Ss were installed.  I have other Stillpoint ultra minis and Ss under my resonating amps and EAR Acute CD player which don't suffer as much as the preamp

Thirdly, within 2 hours SR black fuses in the monoblock amps were my next most important tweak.  WOW.   It was easy two tell the best direction,.The incorrect direction resulted in a hashier, forward brighter sound. The correct sound is warmer sweeter and deeper .   After 12 hours they were fabulous.  I sent away for a higher rated fuse due to their blowing on startup at the manufacturer rating

I installed the SR black duplex and tried it with the bus's an fuses in the amps.   Terrible at first.  Fabulous bass after 30 hours but mids are missing as well as ambiance.  At 60 hours about half way to the SR fuses quality of sound at 12 hours My wife told me give it another 60 hours and she will listen (she confirmed the 30 and 60 hour mark sound)
I know I should wait 100 to 200 hours before listening but I wanted to judge the changes.  I compare is to the Teslaplex SE I have been using.  (I have installed multiple dedicated 20 amp lines for my audio when I built my house)

I've tried other tweaks and some are somewhat helpful and some were not.  These are my favorites.   I also have a Bryston isolation transformer 20 amp and some custom made distribution boxes

Getting the right tube and wiring I don't consider tweaks.   

My my wife is a harsh critic.  She has super sensitive hearing (and my hearing is perfect up to 15k).   She hears and/or senses the smallest differences or none and let's me know yes or no.   I sometimes disagree because I hear an improvement but relegate a loss somewhere else to her not knowing.  But she's always right so I switch tweaks back to where it sounds most musical to her.   E.G.  Magico footers at $1200 a set.  They created a black background and pleasing tone compared to my Stillpoints.  Both Robert and my wife heard a dull musical sound instead.  Totally uninvolving.  Horrible pace.  I agreed and sent them back immediately as I tried them under every piece of equipment and heard the same result

The advantage of running 25 foot speaker wires underground is no one will step on them as they cross the room.  It's definitely cleaner and safer.  Also no electrical interference or carpet caused static. 
80 hours on the duplexes and they are more mid-range friendly but not at the fuse level yet.  

When I built my house I contemplated placing the amps near the speakers by putting in two underground floor duplexes at the speaker locations.  I'm using them for Shakti air boxes instead

Robert agrees but he doesn't hear any loss of bass.   Now with the black duplex, the immense bass is tight, deep and moves enough air that you can feel it.  That's one area that I'm sure is just fine especially with my Grover Huffman large gauge speaker wire.  As to definition, this system way outshines my living room system which has only 6 feet of speaker wire and is driving 3 10" woofers deep and tight, same speakers as Frank.   My wife complained that her Metallica has too much bass on the main system with the new duplex . Otherwise, you are correct with having better sound when amps are proximately located to the speakers.  I can't run balanced cables in my system

100 hours on the duplex with standard fuses. They appear to have broken in so that the mids are balanced with new superior bass and higher treble ranges and the ambiance, reverb, natural decay and air which was awol for the first three days are back. They sound similar to the black fuses. They may require an additional 100 hours to get to that place where the fuses were so beguiling and lush sounding. I will be installing the fuses after another 2 or 3 days just to see how far the duplex sounds.

A25105. The black fuses in my main amps only after only 2.5 hours made my system addictively richer, more detailed, and more musically interesting (until they blew).  They were rated 5 amp slo-blo.   SR Elliott is sending me 6.3 amp fuses.

I also installed a duplex in my living room system. That system consists of highly modified Dynaco ST 70 voltage regulated (not a ultralinear tap design), custom tube preamp, modified pioneer DVD-05 DVD/CD player (six big caps, high end Power cords on all equipment), Kenwood tuner and Legacy Signature 111s.
The black duplex after 24 hours showed great improvement in smoothing out high end peakiness from the rear tweeter, better integration of sound, wider soundstage, and the same punchy deep bass as before. My wife liked it immediately compared for the bad taste from my main system after 30 hours. I will be installing a 4 amp fuse just in case as it is rated 3 amps but SR Elliot recommended the higher rating.

If if you have the Teslaplex SE and replace it with the black duplex, put it on your television/cable box/blue ray player. I have a 75" Sony x940C and it improved the picture. The other big TV improvement (my wife told me to keep the tweak because it the picture was obviously much better) is to install a set of Stillpoints ultra-minis under your cable box.

It’s interesting that in my living room system.i have the amp into the black and other equipment into the red (same 15 amp circuit on opposite sides of the wall). That combo is working well. I will probably spring for a black fuse for the Dynaco ST 70 too

I have a problem with using the black duplex. I have only been using CDs to burn in the system. After 140 hours, I used my LPs for an excruciating hour of trial. The sound on about 10 mixed jazz, classical and pop records of great reknown sounded dynamically flat hashy sounding with really noisy record surfaces and not as interesting as CDs. I experimented with mixing the components into the two dedicated black and red SR duplexes. Immediately the LPs sounded better. The best combo was the two monoblock tube amps into the black duplex and the Bryston isolation transformer with all the other equipment and distribution box into the red. My wife felt this combo also yielded better results for CDs after I decided the best combo of duplexes. (I didn’t torture her with the LP hour). Unfortunately, this combo also lost the blacks excellent ucolored high end ambience and decay retrieval. The sound while more dynamic in macro sense lost micro inflections. Sort of a warmer tubey sound but thoroughly enjoyable for my wife’s rock or my vocals and strings.

I know that the black fuses in the amps will rocket my sound and enjoyment quality.from my too brief 10 hours of listening to them I will ask SR tomorrow if the combo of 20 amp Bryston iso trans and big 125 watt tube mono-blocks doesn’t work on the black duplex even though it works just fine on the red duplex with standard or black fuses. Oh man those black fuses reduced my LP noise on bad vinyl and increased the tonal and dynamic balance to a fantastic level as well as totally cleaning up the sound of any source. FYI. my analog front end consists of a modded VPI TNT VI. modded SME IV. Benz Ruby 3 and custom subminiature tube phono stage with an audiointerface SUT.

150 hours on my smaller living room system.  It sounds so musical and non-audiophile (as in high end systems at audio shows).  The Signature IIIs highs are now totally integrated with the rest of the frequency spectrum.  The rear tweeter always (15 years) stood out and sounded a bit hissy.  Not now.  It doesn't have the tweaks or isolation transformers, Hallographs or Stillpoints of my main system.  I ordered the black fuse for it.  This system is just so satisfying that I didn't think about the missing the large room sound, additional ambience and detail of the main room.   Plus, the living room is a better sound room and the sound radiates beautifully throughout the front end of the house.   All this from a couple of duplexes, black and red.

As to the blown main amp fuses, SR Elliott is sending 8 amp fuses because my big amps have a massive pair of capacitors each as opposed to multiple small caps like most modern amps.  He said that the big caps draw a big instant load and the fuses have to compensate (the SR fuses are rated for typical loads at 5 amps not my big loads).  He also said he heard many stories concerning the idiosyncrasies of the black duplexes and fuses although my situation is rather unique.  If David Prichard finds success in mixing duplexes and I've done the same in my living room system., I can do the same in my main system although that has separate 20 amp dedicated power lines rather than share the same power line as in my living room.

Well I’m up to 230 hours on my black duplexes. Sounds about the same as yesterday. The is blacker backrounds lowering the noise floor for LPs & 78s in particular. There is better transient response superior highs and tighter bass. The mid-range while cleaner is not tonally different.

The black fuses should increase the positive changes but I remember they brought the mid-range sweetness that I thought was magical like a Mac 30 amp. I should be getting them by Thursday.

a25105. Try reinserting the fuses the other direction. I found that after only 2.5 hours a huge difference. By any chance did your system sound more forward brighter and tonally thinner? That’s what the black duplex also sounded like at the beginning. Try the other direction. I heard a darker fuller more distant sound with great slam detail and warmth. It got slightly better after 12 hours til they blew. It’s possible that it just won’t sound good until they break in. It seems these tweaks are idiosyncratic unlike Hallographs which sound great when placed wherever they should be in the room.

I dont understand why most audiophiles don’t address their listening room adequately or overdampen them while the Hallographs take so much of the work out of creating a closer to optimal listening environment. They are not cheap but less costly than one high end cable. Frank, Robert, Tom Port all rely on them too.

dlcockrum
I hope what you stated concerning black fuse break-in is not true for me. The first 5 amp pair I used sounded great from 2.5 to 12/13 hours until they blew. I just received 8 amp fuses and played them for 4 hours. They sound great. When you said fourth day, does that mean running your equipment on for four days or 96 hours continuously? I won’t reach running my equipment for that amount of time for maybe 6 weeks. I don’t want to leave my amps on continuously for that long. Based on your comment will I I be suffering bad sound for 5+ weeks or just 4 days?

I did not have that experience with the black duplexes. On one system it sounded good and got better over a week. The other sounded awful to start, mediocre at 30 hours, broken in sounding at 150 hours.  As to the Teslaplex SE duplexes, the three I installed sounded great at inception and got somewhat better over time.  They never sounded worse over break-in.  They were replacing 22 year old medical grade Hubbles.

I'm quoting myself from 12/22 
As to the blown main amp fuses, SR Elliott is sending 8 amp fuses because my big amps have a massive pair of capacitors each as opposed to multiple small caps like most modern amps.  He said that the big caps draw a big instant load and the fuses have to compensate (the SR fuses are rated for typical loads at 5 amps not my big loads).

I haven't blown a fuse in 15 years in my amps except when a book fell and took out 3 of the top 6 output tubes.  My amps have twin 3" wide X 7" high caps, very big for 125 watt tube amps.  SR fuses may have different melting points as it has been pointed out in a previous post, the variance in melting points for fuses range as much as 400%.  So Littlefuse and Bussman fuses may have high melting points whereas SR may have a low melting point.  There maybe even more idiosyncratic characteristics of fuses which I don't know about; however, I feel confident that an 8 amp fuse in my amps won't hurt them by not blowing if another accident occurs.

I’m laughing because there is no warranty on my amps or preamp. They are Grover Huffman custom designs of which there are four or five made. Obviously, the amps are operating just fine with the higher rated SR fuses and Elliott of SR suggested that I use them because of the huge draw on turnon due to the huge capacitors..

If you read previous posts, they indicated by someone who appears knowledgeable that there exists a range of up to 400% in melting points which may or may not be the same thing as amperage. SR states that their fuses are different than standard fuses and should be chosen accordingly based on the equipment needs, not just as the manufacturer stated.

I am quoting the prior posts below for your edification:

Jon, sorry that you’ve experienced this issue. I have no particular suggestions beyond what Sgordon1 has said (although you indicated that you’ve already performed step 1 of his suggestions), but the following may have some relevance:

I took a look at the detailed technical info for the 0.25A 250V 5x20mm fast blow fuses manufactured by Littelfuse, one of the leading makers of non-audiophile fuses. Interestingly, they offer at least four different series of fuses of that specific type, designed to various combinations of UL, IEC, and other standards, which have "nominal melting points" (defining the combination of current and time that will cause the fuse to blow) ranging from 0.0166 amps squared-seconds to 0.042 amps squared-seconds. That’s a difference of a factor of 2.5, even though all of those fuses are from a single manufacturer and all are 5x20mm fast blow fuses rated at 0.25A 250V.

If the stock 0.25A 250V 5x20mm fast blow fuses in your amp are rated at or near the upper end of that 0.0166 to 0.042 range, and the unspecified rating of the SR fuse is at or near (or even below) the lower end of that range, it would certainly seem to account for what happened. If you call SR, you might ask them if they can tell you what the nominal melting point of that fuse is, in amps squared-seconds.

and this one:

Gpgr4blu, I’m sure Tsushima1 is correct about the physical size and voltage rating of the fuses that are required for your ARC gear, but to clarify about the voltage ratings: The 500v and 250v ratings refer to how much voltage a fuse can withstand when it blows. The voltage a fuse will "see" when it blows (i.e., the voltage that will appear between the fuse’s two contacts) will be the full line voltage. So the higher that rating is the better, everything else being equal. Under normal operating conditions the voltage appearing across fuses having these kinds of ratings will be a very miniscule fraction of a volt. And when the component is turned off the voltage appearing across the fuse will be zero.

HOWEVER, I would disagree with a couple of important things that have been said just above:

1)I would strongly recommend against substituting a fast blow fuse of somewhat higher current rating for a slow blow fuse of somewhat lower current rating. Some time ago, in connection with this thread, I looked at the detailed "melting point" specifications that are provided by the major manufacturers of garden variety fuses. That spec defines the approximate combination of current and time that will cause the fuse to blow (actually, in terms of current squared x time, which is proportional to energy). The upshot is that such a substitution stands an excellent chance of causing the fuse to blow almost immediately. Especially in the case of a mains fuse, where brief but very large "inrush currents" may occur at turn-on.

2)Earlier in the thread there were multiple anecdotal indications that the unspecified melting points of SR fuses are probably a bit lower than those of garden variety fuses having the same current rating (i.e., indications that the SRs blow a bit more readily). And it would seem expectable that in general a fault in a component that would cause a fuse to blow is more likely than not to result in a very large current increase, rather than one that is just slightly greater than the rating of the original fuse. Especially in the case of a mains fuse. So for both of those reasons I would suggest using a 6.3A slow blow in a 6A slow blow application, and an 8A slow blow in a 7A slow blow application. And likewise if an SR fast blow is substituted for a stock fast blow.

Dave, you are 100% correct in your 12/26 post, the black fuses sounded glorious for the first 10 hours, then yesterday and today at 11 to 20 hours, the system sounded mediocre, comparable to mid-fi solid state from the 80's, tonally thin, undynamic, shallow soundstage, hashy, etc. (both fuse directions).  I cannot listen to this so I am taking Frank and your advise in keeping my big tube amps on until after New Years (4 days continuously).  I hope the fuses break-in sounding at least as good as when I first installed them.

There is a question which I haven't seen answered.  Do large amperage, slo-blo fuses take longer to break in than low amperage fast blow fuses?  Frank suggested it may not matter when I asked him due to the graphene and other dampening compounds which take the same amount of time to break-in.  

Lastly, I would greatly appreciate a company that breaks in their products. For the fuses, I would gladly pay 50% more instead of burning up my tubes waiting for the fuses to be listenable.

First, my wife is a very impartial and impatient person who I inflict my audio changes to. I did the same A/B test that an Optometrist does to a patient. No hinting as to which I preferred. She indicated she clearly preferred one direction over another and it was just as obvious to me. Same in both audio rooms systems.

Second, after 33 hours burn-in time, the fuses sounded mostly as good as they initially did. I listened every 10 hours until 70 hours when the sound was quite exhilarating. Record noise diminished 75% (alot) and the pleasure of hearing records with less than good vinyl or condition was tremendously improved. It’s more effective than adding the SimplyVinyl SugarCube pop and click remover but better since it removes even more vinyl noise.  I intend to add that device next year to my tape loop for 78s and LPs with lots of pops and clicks (we are talking 1000s of records).

Third, CDs improved in similar ways but I have an idiosyncratic sounding EAR Acute player because I use the earliest stock Amperex 6922s which have huge tonality, dynamics, mids and bass with a rolled off high end (slightly covered sound with less ambience) when I listen at the increased global feedback setting on my amps (I have this feature in 2 db steps from 2 db to 8 db range). When I use the minimum feedback, I have a leaner, less tonally rich sound from CDs (perfect for my LPs & 78s) but great ambience and openess as well as slightly tighter bass. I think it’s time to change the fuse in the CD player (which is plugged into the Teslaplex SE not the black duplex). That may alter the sound beneficially. I’ve tried about a dozen other NOS 6922 brand tubes and they just don’t sound as compelling (i.e. gold pin Amperex have fantastic mids and highs but no bass, Siemens were dry and lifeless, etc with the stock JJs okay comparatively speaking).

As I’ve stated before and as several other contributors have said, they’ve tried many tweaks over the decades. Some work, some don’t. The degree that they affect the sound also varies. Almost all of our audio systems are different. One naysayer should get off this site as he does not contribute anything positive, only cynical negativism to our enjoyment of our avocation..

As to why such great recordings were made in the 50’s and 60’s, first they used simpler but effective power supply and design technology (and cleaner A/C lines back then-no digital hash). Second, they used state of the art tubes with metallurgy unavailable today with proprietary construction. Third, simpler miking, done correctly to capture the sound and not so much the ambience aka wrongly miked recordings by Yarlung today as an example. There are probably more reasons which I can’t think of currently.

I’m so excited about my "new" audio system, I’m going back to listen for another few hours.

Robert came over to hear what 2 fuses & a duplex has done to my system.  He thought it never sounded so rich and detailed; however, he used his critical ear and heard a slight closed in sound and lower mid suck out.  He told me that the.side wall center hallographs had to be moved further apart as they were set up for the old fuse sound (like electronic distortion-the new fuses sound distortionless with a black backround).  

After he left, I spent an hour testing various depths and 9" back to side walls sounded best with a zero array setting. It had a soustaging and immediacy problem though.  So I moved the rear hallographs inward first 2 notches then 1 notch. Voila!  Great success. The tremendous fuse&duplex sound was surrounding me with a continuous soundstage in front of me from beyond my speakers, I have a dynamic and tonally rich, detailed sound. I found I could enjoy music at low listening levels and as loud as I can tolerate.  

Previous to the fuses, I could not enjoy low listening levels, the sound was just not rich and dynamic.  I am going to buy fuses for my tv system and CD players.  The fuses are transformative.  I've spent most of the weekend listening (my wife had a cold so I wasn't interrupting any engagements).  When I opened the door, she heard the music flow into the adjacent bedroom and commented on how warm and lifelike the music sounded (the Klezmorim was playing a dynamic and colorful ensemble closely miked).  That's the first time she had no negative comment in decades.  The cost for this upgrade is nominal (as long as the fuses don't blow).

Thank you Frank and David as well for your support. 

Kedoades, you can obtain Elliott’s recommendation at Synergistic Research. I had to move from a 5 to an 8 amp slo-blo fuse due to the immense size of my custom amp’s capacitors. He recommended the same as rated size fast blow fuses for my solid state 1978 Yamaha receiver and ADS speakers (for the tweeters). He also recommended a 4 amp instead of 3 amp standard slo-blo fuse for my Dynaco Stereo 70 (modified) which is a tube amp. So, it is equipment dependent as to using the same size versus larger size fuse. The fuses on both amps changed the sound 100% for the better-superb after 150 hours of use.

Yes, the trolls are out tonight.  I don't care for the definitive reason(s) for the SR fuses *and duplex outlets) making my amps creating sound in my listening rooms that are so superlative versus just very good, everyone who has heard the result can testify that they never heard a better sounding audio system.  I don't have SOTA equipment, but it's high end gear, wiring and tweaks (all my stillpoints, hallographs and isolation transformer). 

Why are these trolls so interested in our (high end) fuse users welfare?  

FM Acoustics also makes a record denoiser device requires much more user knowledge (the sugar cube is simple to use). And sells for $37,500. Ouch!

Highstream. I find that the SR black fuses increase the color and certainly the texture of instruments. The added detail and ambience give more life to the music, not just leading edge transients. Maybe in his system the SR fuses aren't working well.  

I have 7,000 78s and 100,000s of pre-LP recordings on CD and Vinyl. I play my 78s on a VPI 19-4 Ultracraft AC-400 and Grado elliptical cartridge.  While this cartridge is acceptable for most post 1925 electric recordings, I don't get the best sound out of my acoustic 78's due to the various stylus sizes needed to track them correctly.

 There is a new device called the sugar cube by simplyvinyl which eliminates pops and clicks and for now, gross surface noise from all recordings.   It is being designed with 300 equalization curves for use with 78s. It uses a closed wireless system using a computer, iPad, or phone.  It apparently does not alter the recording and has adjustable amount of noise eradication.  It even has a switch to hear exactly what noise is being removed.  Cost is $1500 and $2500 depending on additional features.  It upscales to 192/24 rate and outputs many multiple digital rates.  

As to 78s sound, they can be very exciting to hear in my high end system.  I especially enjoy Marston records CDs of historic singers and pianists.   Edison made near silent surfaced 78s from 1910-1914 which were never released so Ward Marston mastered 6 CDs with virgin pressings.  They had smaller grooves with extended playtimes at 6 minutes for 10" and 10 minutes for 12" records.  I can't wait to use the sugar cube on my 78s and defective LPs.

i could ramble on and on about.pre-LP recordings as they often contain rare and precious music.  

Wolf-Garcia and Georgelofi (your name indicates your concern for audio sound quality)-Leave this site to the believers.  We don't want or need your sarcastic, uneducated remarks. 

Audio equipment which can measure the same (such as amps), can sound vastly different (unless one is Julian Hirsch).  Tubes and wire can measure the same and again sound totally different.  LPs which are pressed consecutively using the same stampers can sound very different.  Why, that is mostly unknown except for equipment which may mean the measurement of difference was not measured. 

As a former commercial real estate appraiser, I made adjustments to sales and rentals based on factual data.  Unfortunately, data was often missing which could have influenced the adjustments.  I had to make an educated opinion as to which facts were given more or less weight in the adjustment.  (Complex properties involved much more complex adjustments than illustrated).  

However, my point is that the SR Black fuse in my audio systems has a profound positive musical affect.  I do not know why it does so but I (and over a dozen friends and remastering engineers) hear the result.  That is why buying LPs on-line is often a crapshoot with sellers often unknowlingly ascribing incorrect condition to them either by ignorance of factors in determining condition or hidden condition (mint looking but poorly manufactured or abused i.e. mistracking, ground in debris, etc).

I know this could lead to another round of controversy, but multiple pressings of CDs can have variable audio quality from the same pressing plant, in other words, they don't sound necessarily alike.  There is no electrical or physical reason that I've found or my friend Robert has found, but the proof in the pudding, listening to one after another.  One CD can sound brighter/duller/tonally richer/thinner, etc. than another or they may sound alike.  I have two complete sets of the classical Mercury Living Presence CDs (as well as the boxed versions) in which many of them have tonally different sound, one set is generally brighter and more forward sounding and the other more rounded and less forward sounding.  It's a mystery as to why it is that way. 

Low bass performance on the Mercury CDs are not lacking at all in any of the 3 pressings. They sound veryI focused, dynamic and tonally correct. I also have about 50 RFR and FR Lps and most of the Golden Presence(?) reissues. The early LPs vary in sound quality much more than the CDs. I highly recommend the CDs and reissues. My primary CD playback equipment consists of an EAR Acute player with early large O getter Amperex output tubes, Stillpoint ultra SS and custom wiring. Even on my Kyocera 310 CD player, the CDs sound great and analog like.

GK, I also have a quasi-high end analog set-up, a VPI TNT VI mod./SME IV mod./Benz Ruby 3, isolation platform/Audio Interface SUT and $15K custom phono stage.  About $30K+ and properly aligned.  I just counted 79 RFR and FR pressings.  I have heard all but 3.  Generally, they are excellent; however, vinyl noise is a factor on many of them and the bass is absolutely not better than the MLP CDs.  My speakers play down to 16 Hz with 3 12" drivers.  As to your mischaracterization of the CDs, I don't know what you are using to play them on and I have already stated my EAR Acute based system.  I do not hear reversed polarity at all.  I hear sound usually at the apex of all recorded sound for the period.  Tremendously enjoyable.  There were some miscues in remastering such as in the first cut of the HI-Fi a la Espagnola or the dry sound of the mono release which I can't remember.   The Starker CDs sound fantastic, equal to the LPs without surface noise.  As to differences in sound by the different sets, they all sound excellent, just a little different. 

On Capitol Kids Songs for Grown-Ups, I've heard 5 CDs, of which I own 3, Robert owns one and Tom Port of Better Records owns 1.  2 of my 3 copies are less dynamic and less focused sounding than the other 3 copies.  So, we listen to the best copies instead.  As I said before, the variability is present, just not as prominent as differences in LP pressings.

I improved my system by about 20% of what the fuses have done by replacing the 6SN7 cathode follower tubes in my amps today. I had 1950s GE tubes which Andy of Vintage Tube Services stated they are mediocre at best. He told me to stick with RCA and Sylvania tubes. I purchased a pair of Sylvania 6SN7 GTB 1950s tubes. The manufacturer told me that the cathode follower tubes all sound the same.  Wrong.  The improvement was immediate. Superior ambience, greater micro-dynamics, clearer sound. Sounds a lot like the benefit of the fuses but not as dramatic (the bass, mids and macro dynamics sound about the same other than the enhanced clarity).

As to comments about audiophile designations, I am probably only a borderline audiophile based on my having mostly decades old equipment, 10 year old CD players (EAR Acute), analog gear (VPI TNT VI, Benz Ruby 3 other than a modded SME IV arm from 1989), 15 year old custom amps, preamp, phono stage, 23 year old speakers (Legacy Focus & Sig IIIs), 50 year old 2nd system with highly modded Dynaco ST70 and 18 year old highly modded CD player. The only changes I’ve made in the past 10 years are to the tweaks, Hallographs, Stillpoints, Fuses, Duplex Outlets, Wiring and a Bryston 20 amp isolation transformer. I’m more concerned with the music than the sound which is why I have 42,000 records and CDs. I spend more time listening to music than watching TV despite having a 75" 4K 1 year old Sony with all the software, channels and Android apps one could want.

George Jetter,
I have a dedicated music room 25’ X 23’ X 12.6’ high with too many records on the floor but mostly in custom wall shelving. Also about 5,000 of the 7,000 CDs are in metal drawer cases. The records and CDs which are put away on walls and cases are filed in my computer; unfortunately, I’m too busy to list about 8,000 of them (arrivals in the past 10 years). I will attempt to post photos in the future.maybe through a URL?  I had no damage from the 1994 earthquake due to the shelving, 6" concrete floor with tied 1/2" rebar and 8" to 12" thick exterior walls. 

I want the moderator of Audiogon to get rid of Wolf-Garcia and Georgelofi from this blog.  As he or she can clearly read, they add nothing to the discussion, only disgust. 

I recently replaced my stock power cord for my Bryston RM 20 power conditioner with a custom made Grover Huffman 20 amp a/c cable. It is more open sounding and clear. Music is sounding faster with more detail and less glare. Now I inserted my system which is plugged into the Bryston except for amps into the SR black duplex whereas I previously preferred the amps in the black and Bryston into a red duplex both dedicated 20 amp circuits. Now, with everything plugged into just the one black duplex my sound is even more dynamic, clear and interesting. SR is doing something right in their fuses and duplexes which allow high end equipment to reveal their best qualities as well as the music.

Thank you Frank for the effusive compliments on my audio systems.  The Altec amps only have the casework and transformers remaining.  At SR, the tech suggested 8 amp fuses after the amp rated 5 amp fuses blew.  This was after I informed him the the amps have two massive (7" X 3") storage caps which cause a great sustained inrush of power to fill.  On my solid state gear and speakers for my Video system, he told me to stick with the rated fast blow fuses. 

Grover Huffman uses the Mel Torme CD for auditioning equipment such as at the Newport Show.  As to Sinatra, there are many very fine CD/LPs which match Torme although I have many of his as well.  Remastering of his Capitol LPs on CDs has been an issue with the earliest being weaker sounding and the Norberg 2000 period remasteing ruined with his overuse of Sonic Solutions software, filtering out the highs.  I found an excellent reissue box from UK which has the best sound for the Capitol mono LPs which are very inexpensive (probably the reissue of the very expensive UK older set).
https://www.amazon.com/Capitol-Years-1953-62-Frank-Sinatra/dp/B00OAF8D3C/ref=sr_1_7?s=music&ie=U... There are several top quality remastered Columbia 78 CDs as well including Andreas Meyers
https://www.amazon.com/Essential-Frank-Sinatra-Columbia-Years/dp/B00009PJS2/ref=sr_1_1?ie=UTF8&q... no reverb added remastering

The last item I want to address is the increased benefit of the Black SR over the Red SR duplex outlet.  It's effect is the same as the fuses but less prominent in my system once I installed the Black fuses.  I haven't tried the Black outlet with standard fuses and I'm not going to bother. 

Both my Altec and Dynaco ST70 amps are not conventional and are voltage regulated designs.  Grover dislikes ultralinear amps so his designs are different.  The Dynaco is the best Frank or Robert ever heard and it's not expensive to change a few components and the transformer tap.  Superb tight and deep bass from a ST70 is a rare thing, going down to 20 Hz on my Signature IIIs.

Well, I installed a slo-blo 4 amp fuse on SR advice as a 3 amp may blow too easily. It removed an upper end brightness as well as tightened the imaging bass and brought out more detail, more music. Then I plugged the whole system into a black SR duplex (free fuse with the duplex-a win win situation)

The amp does not use the ultralinear center transformer tap. I don’t know what Grover does exactly but it changes the amp from slow to fast, deep and powerful. He installs a storage cap which runs diagonally nearly the length of the amp underneath. He installs solid state rectification but keeps the tube for soft turn-on purposes. The 7199 tube is really a great input tube and some modern designs use 12ax7s instead. To get the fabulous dimension, dynamics and tonal richness I have mullard el34s. You could phone Grover for advice on the design. He’s behind in making cables so he can’t do any mods right now. I have another amp waiting to be modded for over a year. Of course I am using his tremendous bargain Empress cables throughout my systems.

Yes Jetter, those are the old stock Mullard EL34s.  I haven't tried any new stock EL34s as of yet but may for another Dynaco I'm waiting for Grover to modify.

I just read the recent posts and Morini on Brahms is a favorite.   Other favorites of mine are Szyerng on Mercury, Kogan on EMI and Milstein on Capitol.  I probably have a 18 performances but those four stand out in front of the Heifetz.  However, none have recorded the Sibelius concerto sounding like his RCA or many other works.  Heifetz 50's recordings were especially fine/outstanding.

A retail dealer informed me that VAC audio only uses high quality ceramic fuses and does not recommend ordinary glass Bussman or Littlefuses.  Sure it's not black SR fuses, but VAC wants to make a profit and finds better quality, lower cost ceramic fuses are minimally adequate to protect their gear and sound good.  VAC amps are high end in build quality and sound quality.  

Has anyone on this forum broke open an SR black fuse and analyzed what it is made of and constructed?   Who knows, maybe it does not have a hair thin wire but a thick wire made of some other substance.  Maybe it has anti-vibrational content differing from cheap basic fuses.   Finding out what and how it is made could answer questions as to why it works and so well.    In the meantime, I'll just keep listening to my fuse induced sonic improvements.

Robert and I use this CD which he introduced me to, for testing equipment and changes in our audio system.   If it doesn't sound great, there is something wrong with the system.  I found out that my mid range drivers on my Focus speakers were lacking in polyester batting due to the hard and blurry/blurry horns.   Upon remedying the problem, horns sounded rich and smooth.  These were not due to factory error but the guy who rewired my speakers prior to purchase didn't replace the batting which they needed plenty of.   Great CD!