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Shindo schematics?

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Well, the 6SN7/300B combi is a very good thing, I 'm using monos with 6SN7/300B SE NFB (I have many power-amps).

We have to seperate here between audiophiles and vintage tube addicts. Mr. Shindo is not interested in the best possible sound, he is a religous fanatic using only horrible sounding outdated parts. The people who believe that Shindo sounds good are people who do not have the slightest clue about parts and how they alter the sound. I've used my own monos in a listening test against the Palmer and the owner of the Palmer told me that it was the most horrible sounding amp he ever bought. I had the feeling that it was completely undynamic, lifeless with extreme problems in the freq. extremes. No bass no body no textures - 2D sound stage. Looking at the parts Mr. Shindo used it is self explaining - I would use the parts in the Palmer not even in an old tube radio. But rip-off is normal in the Audiophile scene, and the people of the german hifi-press are industry-paid disgusting idiots who do not understand the SLIGHTEST thing about circuits and electronics...

Best regards
ElectricHead
 
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Konnichiwa,

ElectricHead said:
Well, the 6SN7/300B combi is a very good thing,

Sorry, but that is not my experience. Usually you must plenty of parts that are distinctly non-neutral sounding to get anything approaching life or reality out of 6SN7 cascade 300B. I have herd them all, Reichert, JE, ANUK all the same stuff. Boring, congested and excessively euphonic, simply "pre-clear".

The Palmer was an exception, as it kills the charater of the 6SN7 by applying a good deal of negative feedback around the 2 6SN7 stages.

Shindo San's parts choices are controversial, agreed and they do not make for neutral sounding amplifiers, but that is not his point.

For Shindo gear I'd say around 50% of the sound is the parts used, another 30% are certain special tricks he applies (such as the feedback loop around the input/driver stage and the undersized output transformer in the Palmer, plus some I will not mention here), the remaining 20% are the schematic, hence having the schematic for Shindo gear is not particulary useful, without having the matching photos of the implementation too.

The sound of Shindo, it divides the spirits as they say, you either like it or not, few people can be anything except being polarised that way I noticed. I like Shindo Sound but in the long run it is a little too "chocolatey", for want of a better word.

Sayonara
 
@Thorsten:

Well, you are right about the sound of the different implantation of the 6SN7. But please don't try to defend Mr.Shindo. I heard his completely unlistenable amp's espicially the Palmer. I'm tolerant to different tastes but a 300B amp without any bass or body (violins without wood) are not worth a discussion, not the mention the 2D stage like a cheap japanese transistor amp.

Without using Lundahl transformers, chokes & fast caps it is not possible to build a neutral and fast 300B amp, if you want to carry it further the speed and detail lane than one might also consider an EF86 instead of a 6SN7.

Looking at Shindo strictly scientifically it is a clear RIP-OFF period.
 
Kuei Yang Wang said:


...hence having the schematic for Shindo gear is not particulary useful, without having the matching photos of the implementation too.

Sayonara

Yeah, that is right.

Good sound MUST have a material base, i.e.: An amp with mediocre parts can only sound mediocre, good parts don't mean automatically good sound. But without a kind of quality material standard you can't reach high levels of audiophilia.
 
Konnichiwa,

ElectricHead said:
a 300B amp without any bass or body (violins without wood) are not worth a discussion, not the mention the 2D stage like a cheap japanese transistor amp.

I am not sure what you heard and where, in what system context, but this does not sound like anything I'm familair from the few pieces of Shindo gear I am familiar with.

ElectricHead said:
Without using Lundahl transformers, chokes & fast caps it is not possible to build a neutral and fast 300B amp,

Lundahl transformers are okay, far from the best though. Solen SCR "Fast Caps" have no place in quality audio gear, their tone is revolting, even black gate are preferable to these.

ElectricHead said:
if you want to carry it further the speed and detail lane than one might also consider an EF86 instead of a 6SN7.

EF86!!?? What for. Try an EL84 triode wired instead....Actually, you may wish to consider a design more like mine, if you want speed, detail, resolution, dynamics and a sound that is smooth, relaxed and makes you want to listen more:

http://www.jogis-roehrenbude.de/Leserbriefe/TH-Loesch-Amp/Th-Loesch-Amp.htm

You might also check the recent D3a/300B DRD Amplifier thread for some ideas that I was able to input to Luis's design and realisation.

Key things to get a neutral sound from the 300B I found are:

No ECC99, 6SN7, 5687 et al cascade, absolutely NEVER EVER repeat the same valve twice in the driver stage.

Used as cascode this is another story, see penthode.

SRPP/Mu Follower et al is best avoided, it can do okay implemented with care, but usually it causes more problems than it solves.

Preferably ratchet up the Gm in the driver valve quite high and the anode impedance down, then SRPP et all are not needed, you have gain and drive readily available.

Never use more stages than absolutely needed.

Going 3-Stage (including powerstage) is okay if you use fairly powerfull low gain drivers (2A3, 45, 300B, 10, 205D, 6L6 et al) and low gain input valves, but most of the times 2 Stages (including powerstage) are preferable.

Example would be 6SN7 input and choke loaded 6BX7 driver, this is miles preferable to a resistor loaded 6SN7 cascade, but you start to cook seriously with a 417A or other highish Gm input valve and a 2A3 or KT66 as driver, IT/Choke loaded.

With Self Bias use the WE connection, if you don't you are missing the top 20...30% of the perfoirmance (dynamics, maturalism of sound) the Amplifier is capable of.

With fixed bias add a decoupled bypass to the last PSU capacitor.

The 300B requires DC Heaters (AC sounds foggy and indistinct - I need to try HF AC, that may be a happy middle) but these require utmost care in implementation in order not trade fog for severe glare and edginess.

Single stage pentode drivers (310A, EL84, C3m et al, the three mentioned I have build with) tend to have more delicacy and immediacy plus more than enough gain, tonal colours are rich and natural.

Triode drivers are a little more solid sounding and better on coarse dynamics, tonal colours are little bleached out.

Driver triodes need inductive or IT load = more delicacy, resistor load usually not recommended.

No Black Gates.

No PIO Coupling Capacitors.

No FastCap's.

If you can replace a resistor by a choke sensibly, do it.

Direct coupling usually swaps a good quality capacitor for a poor quality one, the results are unpredictable. If in doubt eliminate the cathode capacitor before a gridcoupling capacitor and remember, current flows in loops, if you do not give the signal current any other way to go the loop will complete through the Powersupply.

Output transformers with very high primary inductance for whatever resons do sound not right in the bass (and often equally crappy in the treble due to excessive leakage inductance), don't ask me why, but they don't (I suspect several things at work there, to early to talk much).

45's sound better than any 300B's, as do 10/10Y/VT25, if your speakers tolerate 1.5 - 2 Watt amplifiers.

Well, I'll add some if I remember any more.

Sayonara
 
Jesus, quiet a lot of information from you.

1. I have a lot of schematics from you, I think you are very serious about sound quality so I really respect you.

2. Which transformers you consider better than Lundahl?

3. Black Gates are better than Solen? Oh come on.... please don't do that. The only problem the Solens have is the top... but there is a trick....
 
Konnichiwa,

ElectricHead said:
2. Which transformers you consider better than Lundahl?

Various far eastern and european ones using medium - high nickel content.

ElectricHead said:
3. Black Gates are better than Solen? Oh come on.... please don't do that. The only problem the Solens have is the top... but there is a trick....

The trick I prefer is simply not to use them. The locally available stuff is cheaper, better and more reliable.

Sayonara
 
Kuei Yang Wang said:
No Black Gates.

Hi KYW, do you mind if I ask what you consider to be the typical Black Gate sonic signature? I'm at ground 0.2 sorting out some of the things I hear playing with different circuits/parts. BG's have been one of the elements, mistakenly or not, I've considered 'a safe constant'.
 
Konnichiwa,

ElectricHead said:
European? I've tried a lot of different trannies but Lundahl beats the hell out of the rest and even Tamura loses badly!

Tamura (and Tango) make many series, note that I referred SPECIFICALLY to permalloy core transformers.

ElectricHead said:
P.S.: I like Blade Runner too, one of the the very few Science Fiction movies ever made. Are you reading Philip K. Dick?

I have read most of PKD's stuff. I am just revisiting the Strugatsky Brothers, their books come highly recommended as well as Tad Williams (Otherland Series) and William Gibson.

BTW, my tag line will likely change soon to this:

"Ich hörte, dieser Weg führe zum Ozean des Todes, und kehrte auf halbem Wege um. Seither dehnen sich vor mir Umwege, öde und krumm...."

ElectricHead said:
What do you mean with locally stuff? I'm living in Germany, are you really trying to say I should use nasty sounding WIMA MKP's or endlessly slow and dull Siemens or Phillips caps?

Locally to me means Ansar (Supersound) and ICW (ClarityCap). I also can get excellent quality Ducatti Motor run capacitors at my favourite local shop (Cricklewood Electronics) and next door is the best Indian/Nepalese curry joint in London....

Sayonara
 
Konnichiwa,

rdf said:
what [do] you consider to be the typical Black Gate sonic signature?

First, if you like them, don't let me put you off.

Secondly, in sonic terms they are bright, brash, with an unnatural "look how great I sound and how much fake detail I'm adding" style presentation, like the typhical "showroom" sound from loudspeakers with tipped up bass and treble that intionally impresses but tires in the lon g run.

One can partially offset this sound by using circuit topologies and other parts that make for laid back, overly soft and indistinkt sound, but it is essentially constantly fighting the various strong sonic signatures of the various parts to get something that sounds belanced, I find this too hard work and you don't halve pay for it too.

I will use the occasional BG Cap if I feel the need to brighten up a given design sonically, just as I'll use the occasional PIO capacitor to make the sound more laid back, but as a rule I prefer doing things from a neutral point.

Sayonara
 
Kuei, what I read here, this is a typical STD cap characteristic, and I have to agree with that. However, BG N (the red ones) are rather opposite, and when properly applied (with regards to orientation and usually smaller than normally used value) I can put them against most other "exotic" brands and would prefer them, mostly for lack of fake detail, the bass that is not tipped up and the trebles that never tire and are actually rather laid back.

I use standard BG only in GC PS, otherwise I don't like them much, same goes for FK type. However, I can't imagine voicing circuits without N types, all other elektrolytics I tried so far are simply too colored in comparison ( except for some Panasonics).

For coupling, the only caps that are substantially better than N type BG (IMO) are teflon V-Caps. Siemens MKV are OK too, but this is not the same league as V-Cap ( although I didn't try their best grade which really hard to find).
 
Konnichiwa,

Peter Daniel said:
Kuei, what I read here, this is a typical STD cap characteristic, and I have to agree with that.

I have tried others too and at leats in my applications (which are strictly Tube Gear and in places where large values are needed) alos the other series of BG's have this charateristic, some to a larger other to a lesser degree. I tend to take Elna silmic over BG in signal applications every day and in almost any applications, UNLESS I need to "liven up" the sound somewhere in the direction BG's pull it.

For coupling positions I have yet to find anything to better Silver Leaf / Mica capacitors. Secondly I like Tinfoil Film cap's, I found the differences between MIT PTFE types and Solen Polypropylene modest, if audible, but the difference compaed to Aluminum Foil & Polypropylene capacitors drastic.

My current system has a Silver Mica Coupling Cap and a heavily bypassed MKP in the phonostage and one more Silver Mica coupler in the power amplifer. The rest is MKP. No BG, no teflon....

Sayonara
 
Thanks both for the relaying your experiences! For me the toughest parts of circuit tweeking are visualizing (auralizing?) the target, determining if a change was detrimental or exposed an underlying flaw, and finally getting a handle on how others hear and value similar changes to make best use of advice. Right now I'm working at cleaning up reproduction of sibilants on a grid-biased, trioded E180F RC coupled to an SE EL84. The latter is cathode biased with a 100uF BG-N across the resistor so your comment caught my eye. The other caps are an ancient 0.025 uF TRW Polystyrene foil from the kit box up front and a .1 Russian telfon interstage.

I recall reading you prefer the silver micas from diyhifisupply. I'll try the pair of .1 uF 100 volt silver micas I have floating around, admittedly cheapies from Sayal in Toronto, give them a break-in and run interstage to get at least a sense of the direction. Replacing a PIO with the TRW made a world of improvement up top. Will also dig up some Elnas. Thanks again.
 
Konnichiwa,

rdf said:
Right now I'm working at cleaning up reproduction of sibilants on a grid-biased, trioded E180F RC coupled to an SE EL84. The latter is cathode biased with a 100uF BG-N across the resistor so your comment caught my eye. The other caps are an ancient 0.025 uF TRW Polystyrene foil from the kit box up front and a .1 Russian telfon interstage.

First, what opertaing points do you use? Especially the E180F can sound bright and steely if the anode current is too high, try 6mA or less, given that you probably have a low anode voltage as well.

Secondly, both E180F & EL84 are very high transconductance, stick 1K gridstoppers on anything that looks like a grid (screen, suppressor etc.), even if you triode wire the valve. Also, if you triode wire remember to take any freely available suppressor grid to the anode, rather than the cathode.

Thirdly, go for fixed bias on the output stage as well and as the EL84 has loads of gain and transconductance apply cathode feedback from the output transformer secondary (observe correct polarity) to the cathode of the EL84, in other words connect the EL84 cathode to the output transformer secondary so that you attain negative feedback.

Forth, the EL84 is extremely eay to drive, try an unbypassed cathode resistor to bias the E180F, if you get too much top end rolloff add a small value silver mica "tuning capacitor" across this unbypassed cathode resistor to get any drooping trebel response back up.

Fifth, remember the that output stage current loop is completed through the powersupply. The final powersupply capacitor matters a lot sonically. You can add a modest value (22..47R) series resistor after the final electrolytic capacitor with a largish motor run film capacitor (22uF or larger) to ground as effectively "decoupled bypass" capacitor.

You might find that with only one coupling capacitor and one PSU capacitor plus local feedback in both stages for better linearity will make this a wholly different animal.

rdf said:
I recall reading you prefer the silver micas from diyhifisupply. I'll try the pair of .1 uF 100 volt silver micas I have floating around, admittedly cheapies from Sayal in Toronto, give them a break-in and run interstage to get at least a sense of the direction.

Beware, Silver Mica are in my experience the capacitors closest to a piece of wire... This can be a bad thing.

Sayonara
 
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