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LC
Dear Andrew,
thanks for the precious feedback on this topic. Perhaps your experience of mixing and matching different types of resistors will be useful for other TNT-Audio readers! Unfortunately I don't have the time (and, perhaps, will :-))) to perform these tests on my own...
Thanks and happy mix & matching!
Lucio Cadeddu

Re: Grain
Thanks for the clarifications. Here is the punchline: replacing the tubes in my Audible Illusions M3B resolved the issue. It is funny. I have been using tubes for decades, and never experienced distortion due to aging, which I associated mostly with loss of upper frequency content. I need to study tube theory a little more.
I am rather sensitive to LP wear, and am quite familiar with its sonic characteristics, and this sound of tubes dying was different. Just recently I actually toured the country with a set of 10 LPs, headphones, preamp, headphone amp and cartridge to audition LP setups. A standard part of my audition of each setup was to listen to all 10 LPs near the edge and center, to asses end-of-groove degradation. Schroeder's Linear Tracking (LT) tonearm won this aspect of my auditioning. Also, I am familiar with mistracking and its audible characteristics.
Just as an exercise in logic, for the terms above, I can give the root causes, the sonic characteristics and cures or mitigations. As background, I am defining harmonic distortion as an audible increase in upper harmonics of well tuned music and intermodulation distortion as the introduction of non-harmonic components to well-tuned music. Because music typically has a harmonic structure, it can be difficult to differentiate “non-linear” harmonic distortion from linear changes in frequency response. For pure sine waves, it would be the introduction of harmonics. Practically, for music, it will be the increase of upper harmonics wrt. the fundamental.

Wear. Root cause: the shape of the groove is changed by the passage of the cartridge. Characteristics: gets worse with repeat playings, increases in harmonic and intermodulation distortion, is greatly accelerated by mistracking (discussed below). Cure: get another copy of the LP.

End-of-groove degradation. Main root cause: error in rotation of cartridge about the vertical axis “horizontal tracking error” (HTE). (Minor root cause: the linear velocity of the groove is lower and the spatial frequencies of modulations are higher). Characteristics: loss of spatial information and increases in both harmonic and intermodulation distortion. Cure adjust the “overhang”. This cure is partly practical and partly in principle. For standard pivoting arms, there are 2 points across the radius of the LP where horizontal tracking error can be zero. Picking those points to minimize some average of the HTE in some sense is the practical solution. However, for most pivoting tonearms end-of-groove degradation cannot be eliminated across the whole radius of the LP.

Mistracking. Root cause: the stylus does not remain in contact with both walls of the groove so that it can “bang around” in the groove. Characteristics: somewhat binary nature: its either happening or not, is easily observable on various test LPs designed to test tracking, and gives dramatic increases in harmonic and especially intermodulation distortion. A “cure” is often to increase the vertical tracking force, although this may be accompanied by various other degradations in system performance.

So, kind of philosophically, can a similar description of “graininess” be given with root cause, audible characteristics (or reproducible examples) and cure or mitigation? Or, is “graininess” vague with a meaning (within audio) that can change substantially with context?
Fred - E-mail: fstanke (at) comcast.net

LC
Dear Fred,
I'm glad to know that new tubes cured the “grain” problem. Unfortunately I can't find a proper definition, not to mention a cause, for what you/we call graininess. For this reason it seems the answer to your last question is substantially YES! :-) The meaning is vague, as it always happens with audio-related words. Think of warm, edgy, open etc. I know several audiophiles who give slightly different meanings to these frequently used audio words.
Happy listening and thanks for the feedback!
Lucio Cadeddu

Ultimate "active" speaker
Mark,
Thought you might be interested in my recent experiences. I decided I wanted to find out how good some of the most lauded speakers actually sound so I selected 3 that
(a) have consistently received the very highest praise
(b) are from manufacturers that invest extensively in R&D and come at speaker design from a solid scientific base. The 3 were:

• Vivid Giya 2
• KEF Blade 2
• Revel Salon 2

MW
Hi Ian
Thank you for sharing your experiences with me. It is certainly unusual for a manufacturer or distributor to recommend a rival product and Revel are to be congratulated. While European manufacturers often used to prioritise low colouration and accurate balance in their monitors, American manufacturers usually tended to prioritise low distortion motor systems and accurate dynamic range. Although there has been some convergence over the last 3 decades, a comparison of the catalogues of JBL and B&W, for example, suggest this trend still applies.

I will stick to USA pricing, as that's their country of origin and currency markets are currently so volatile as to be out of date by the time this is read. The JBL 4367 is sometimes also designated by them as a studio monitor, and the 4 digit codes used to be JBL nomenclature for 'pro' (like the JBL 4412) while names were given to domestic cabinets. At $15,000 they are not cheap. Unlike many of the old school 4-digit models they arrive with a domestic in-built passive crossover (and the Plebs Chorus is very familiar with my views on that). The horn (HDI Waveguide in JBL-speakis slightly different but the D2430k compression driver behind it is the same concentric dual-voice-coil dual-diaphragm much vaunted by JBL these days.

The JBL 4367 also shares most of the bass-mid unit, the JBL 2216Nd 15" but with a different surround and rear spider, presumably better suited to domestic environments. The JBL M2 usually ships as a package of 2 loudspeakers plus 2 Crown I-Tech 5000HD amplifiers, BSS Omnidrive HD & Crown Macro-Tech® MA-5000i & software. This lot could set you back $20,000. Crossover point is 100Hz higher at 800Hz with a more complex treble horn shape and the cabinet is taller, narrower and more industrial looking. Without the electronics they sell for $12.000 per pair.

Compared to the passive crossover domestic version they do look excellent value and a commercial crossover would work as well as its price point implies. Being a 2-way system, the JBL M2 warrants money spending on good amplification and it might also be worth trying linear amplifiers (comparatively inexpensive used Naim and Krell could be easily resold if unsuccessful) as well as the various digital architectures. I will take your advice and check them out next time I visit a pro sector supplier. I hope some of our readers will heed your suggestion to cast their nets wider than the domestic audio market.
Happy Listening
Mark, the Old Scribe

Mark Wheeler

Re: Toshiba SD 9200
In the process of purchasing this player knowing of the transport vibration issues but it being such a good buy in my opinion for $50 I thought it would be worth the risk. The gentlemen being frustrated trying to repair it with the damper kit not being available decided to sell for very little. Would you know of any tweeks to help repair this issue?
Thanks for any advice.
John - E-mail: sowersjohn13 (at) gmail.com

LC
Dear John, unfortunately we don't have the knowledge to help you with this repair but, certainly, publishing your request here on the TNT Readers' Corner will help you somehow, as many readers use open reels nowadays and perhaps they know some good technician who can help you in solving this issue.
Regards,
Lucio Cadeddu

Re: Grain
Lucio,
Thanks for the response.
I guess my question has 2 motivations. On the one hand, “grain” is used in various audio publications incl. TNT-Audio, and I simply want to understand what the term means: both empirically (what does it sound like) and theoretically (what causes it).
On the other hand, while I have been delighted with improvement in sound quality of my system after the inclusion of the Helix+LT, on several albums, while the sound quality on low-level passages is magical, I notice degradation as the modulation levels increase.
Connecting the phono preamp to the headphone amp is a good suggestion that I had tried. The problem with this, in this case, is that the M3b has solid-state output buffers on its tape outs which noticeably degrade the sound vis-a-vis going through the line section and thereby bypassing the emitter followers. So, for this second branch of the question, I am coming to the conclusion that I am being bothered by a confused combination of record wear (which I now hear more clearly with the Helix+LT) and (surprising) overload of the M3B's line stage.
But going back to the first motivation, I would still like a some clarification of what the audio press mean by “grain” and its root causes.
Best regards,
Fred - E-mail: fstanke (at) comcast.net

LC
Dear Fred,
generally the word “grain” is referred to a sound which is not “smooth”. I guess it derives from the same word used in photography. When referred to an image it might be easier to understand than when referred to a sound. Which are the causes? Lack of definition and distortion can lead to this effect.
In your case I'm pretty sure the problem comes mainly from the wear status of your vinyls and by (wrong?) set-up of your tonearm/cartridge combination (tracking force, antiskating, geometry etc.). Moreover, there are many recordings that sound good on low-level passages and become distorted as the modulation levels increase. Finally, don't forget the inner grooves of an LP always sound worse, because these are much more difficult to “track”.
Even input stage overload might cause sound degradation, you might trying lowering the level by means of RCA line level attenuators, like these by Rothwell we reviewed years ago.
Hope this helped somehow,
Lucio Cadeddu

Re: Daphile
Dear Nick,
Have you heard any positive or negative comments in regards to Daphile. I wanted to use AP-Linux. However, my laptop has gma-500 graphics and that has always been a problem with any linux ditro. My only option is to pay for j-play.
David - ksdb010 (at) hotmail.com

NW
Hi David,
This may sound drastic, but you can buy an ultra small form factor (USFF) computer with an i3 CPU and 4 gb of RAM for around 50 UK pounds. That, and AP-L would give you a very good music playback system.
Regards,
Nick Whetstone

Cabasse Jersey

Hi!
Please help me, I can't find infos on dynamic range. I only know the sensitivity is 91 dB/w/m. Thank you for your answer.
Yours sincerely, one owner of Cabasse speakers.
Laszlo - E-mail: lszamek48 (at) gmail.com

LC
Dear Laszlo,
I can't understand why you are so concerned with technical specs. Most of the times, these are absolutely optimistic, quite far from the real thing. Sensitivity and power handling are just two easy and very common examples. Moreover, how is dynamic range spec'd? The only thing you can measure is the maximum pressure level at, say, 1 meter. That depends on sensitivity AND on the amplifier power output. Perhaps your speaker can generate very high pressure levels (and that's the case, indeed!) but your amp can't, for example.
Trust me and trust your ears: the sound your speakers produce seems adequate? Does it satisfy your needs? If so, don't waste your time thinking about dynamic range. Your Cabasse Jersey, if the amp is up to the task, can produce sound levels which are higher than your neighbours can tolerate ;-)
Read my review of your speakers. They can generate (undistorted) peaks of 105 dB at the listening seat (almost 3 meters far from the speakers!). This is an extremely high sound pressure level! Actually, the amplitude of the dynamic range can also be severely limited by a noisy listening room. If the noise floor is high, the dynamic range will be heavily affected, no matter how high the listening level can be.
Hope this helped somehow,
Lucio Cadeddu

Grain
I did a google search for grain and preamps and got a number of hits from your site. I have signed up and poked around a little, but maybe you can direct me. I am a EE and a vinylphile: Miajima Madake, Doehmann Helix TT, Schroeder LT, Audible Illusions M3B, BHSE (EL34's) and Stax 009s. I think that I am having a problem with what I would call “grain” from the tubed M3b. I seek:

1. a good definition of “grain” from the audible/empirical point of view
2. a good analysis of how it arises in electronics
3. practical approaches to deal with grain (E.g., should I change tubes? I have found that if I turn the volume on my BHSE all the way up, and use the M3B (at) ~9:00 the grain is less than if I run them both near 12:00).

LC
Dear Fred,
I'm not 100% sure I've understood why you focus your attention on a single word, instead of trying to describe what happens to your system. Certainly, if the lack of definition and/or distortion (is this what you call “grain”?) occour when the volume of the preamp is set at 12:00 and the sound is better when set at 9:00 there's a simple explaination: the line output level of your preamp is too high for the input of your headphone amplifier. Hence distortion occours, as a kind of clipping!
Turn the volume of the preamp down and find the best combination of the two settings. Generally, it should be better to leave all the “adjusting” duties to the preamp and set the volume of the amplifier at its max. Have you tried to connect a phono preamp directly to the headphone amp? It could be a simpler and more transparent solution.
Hope this helped somehow,
Lucio Cadeddu

Daphile
Dear Nick,
have you tested the "Daphile" software? Is it as good as the "ap-linux? I wonder if any of these are better than the J-play?
Thanks,
David - ksdb010 (at) hotmail.com

NW
Hi David,
No, I haven't tested Daphile. So far, my personal preference has been for Audiophile Linux 3.0 although I am currently reviewing another Linux operating system that takes things a stage further. I hope to have the review ready soon, but be aware that it is a commercial system, and not free as is AP-Linux.
Regards,
Nick Whetstone

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