Tezcatlipoca - Ira, George YouTube description correction

To best of memory, the YouTube upload of Tezcatlipoca - Ira was done by creatiing an mp3 hi resoluction file recorded on m-audio microtrack. Since the masters are on cassette it is an AAD track. The recording session was recorded on analog cassette with date time code 10030215. The mix master was done next day on cassette 10030312, it cannot be remembered if limiter was on, on Sony TC-D5M. Reverb was by Korg DRV-1000. The Angel toy glockenspiel must had been played in real time while the mix master was being recorded. The Tascam Porta One was varispeed from D minor to D sharp minor in order to enchance the vocal properties, so the glockenspiel must had been played on D sharp minor. Tons of reverberation time had been added, by adjusting all knobs at max reverberation time including the turbo knob. Then at a later day after cleaning heads the mix master cassette was played back, the Sony TC-D5M was connected to the Neumann PEV-930-02 passive Eqs (directly connected to m-audio microtrack line in) to reduce excess bass etc and the mp3 master was recorded on m-audio microtrack. The windows video editor must had been used together with the photo sent by Ira to create the video uploaded on YouTube. Is it best to do as least processing and let YouTube do the digital level compression etc?

Fleetwood Mac recording in the studio as seen on YouTube

pleiades radio theme

Brought to attention by Vicky. Key is A minor. Bach bass code is: F7 then E7 then D#3,7. So it is played: E is played sustained by right hand , then bass F and A below E are also added, then D is sustained and then E bass is also added together with G below D, then E is sustained and then bass D is also added together with F sharp and A below E. I summary, (simillarly to Old and Wise - Alan Parsons Project), FACE, EGBD, D#FAE.

Do small foam earplugs for woman exist?

At your risk.

Compensating for voice effort curves by adjusting the anode potential on open grid tubes

At your risk. The softer the voice the more bass and treble (bandwidth)[2] it contains. If we reproduce a soft voice at higher intensity it will sound like bass heavy like mud on a flat frequency responce system as the Fletcher Munson curves come into aditional play too. In order for such a recording to sound correct ie flat frequency response from producer's brain to listener's brain, bass or treble must be cut ie amplifier bandwidth reduced accordingly. This sometimes explain why cheap mics may do an excellent vocal job at certain applications. The softer the voice and the higher the reproduced intencity the less the bandwidth needed. A way to peform such adjustments with least components is to use an open grid electron tube preamplifier stage and adjust just the plate (anode) voltage. At low anode potential less anode current takes place, the higher the anode internal resistance and the higher the bass cutoff frequency by its (ra) interaction with the primary inductance of the electron tube stage output transformer. Conversly for a loud singing voice performace we may increase the Vb supply and increase bandwidth and headroom. A low plate potential can create a very low noise front end amplifier which is convenient for a soft singing peformance. Further reading: Pleiades V6 1H4 amplifier schematic. Sound Picture Recording and Reproducing Characteristics - D. P. Lowe, K. F. Morgan - Journal of the Society of Motion Picture Engineers Operating Features of the Audion - E. H. Armstrong

It seems wise concentrating on good thoughts and throwing away anything that tries to makes us feel unhappy

After a conversation with Lena from Sweden. It is love that makes the difference.

Chorus for dance in 9/8 in D minor

continued from a previous post: Chorus: Bass F, melody A///CBAB. Bass C, melody A/G/////. Bass G7, melody G///////. Bass B, melody F///////. Bass F, melody A///CBAB. Bass C, melody A/G/////. Bass B, melody G///////. Met today bouzouki player Lefteris.

Is Electronics A Systems Approach - Neil Storey published in Hellas?

Pondering about it and whether it would be nice to see it at window shops of electronic parts shops in Athens i accidentaly bumped to Kelly from Kalendis publishers. They may mostly known to me from the children's book The Witch who hated carols. (How about other series such as the Cook who hated vegetable trans fat, The pilot who hated autopilots, the memory stick who hate electrons, The radio who hated transistors, the Youtube server who hated... Science at its higher level is art and perhaps even a fairytale. Richard Feynman got his Nobel price in Physics for his Feynman diagrams which are like cartoons used to solve difficult equations. Look around. Electrons are dancing to music on radio antenas. Radio telescopes receive old photons, grandgrand dad photons from the begining of the Universe or Time?

Electronics A Systems Aproach - Neil Storey

It is currently at it's 6th edition. I fondly remember Dr. Storey lecturing all engineering students at Warwick university huge engineering lecture theater. It was the 90's, we were about 300 students listening attentively to him lecturing, tall, standing up his Analogue Electronics course. There were excellent notes handed on a blue lecturebook. He was showing them in transparences while adding on top other transparency for the text that was missing. So we only hand wrote some of it! An excellent introduction to input, output impedance, maximum power theorem, transistors, class A amplifiers, load lines etc. At the end of the 15 lectures we all stood up and applaud. I then found by chance the 1st edition of his book at Warwick's university bookshop. And he autographed, All the Best, Neil Storey. His faboulus book with excellent explanations is currently read in India, translated in Italian,...

Using entropy to clean our body

At your risk, this is not a medical advice. Bebis the cat is taking long showers or semibaths as a possible way to remove toxins from his body due to kidney desease.

One electron tube, transistor, JFET amplifiers can sound so good

The Pleiades Siemens AC151 seems to demodulate ultrasonic frequency content to audio band. Signal path: 20KHz warbletone from Alan Parsons Sound Check CD - Pleiades Siemens AC151 - output transformer - HD580

How did the misconception arise that electron tubes vannot operate at low anode potential?

Perhaps from the fact that on ordinary common circuits with a cathode resistor, the electron tube is biased negatively 2 times. One by the heated cathode loosing electrons thereby becoming positive wrt grid. Secondly by further raising the cathode potential by the bias resistor. So grid becoming even more negative wrt cathode.

Comparison of 1H4, DC90, DC96, DF97 electron tubes with open grid and low anode voltage

At your risk. Please take all safety precautions. Summary: For mic, headphone tests DC90 sounded best and amazing at just Ia=20 microamperes at Va=18V. This could not be repeated as subsequently anode current increased to 40uA due to unknown systematic error. DF96 was least microphonic. Signal path: male singing voice - reverberant small room - Shure VP64 at 1-12 in - Pleiades V6 1H4 - Realistic disco mixer at mic in - Sennheiser HD580 - listener's, singers' brain). An octal to noval base adaptor was made to make posible the quick insertion of D family electron tubes to the Pleiades V6 1H4 octal base. All electron tubes open grid. 1H4: Sounds great and low noise as always with Ia=20uA at Va=12V. DC90:Ia=1.5uA at Va=12V, low noise, low gain, nice midband edge. Ia=22uA at Va=18V, amazing balanced sound. Ia=240uA at Va=25V, no listening to avoid magnetisation of output transformer. It seems low battery consumption RIAA le Pasific Walthers type pres are possible with electron tubes. To recap amazing sound at 18V, 22 microamperes. Experience makes things easiser to proceed. Vb=12V, Ia=30uAwith 5.6Mohm from anode to grid. VP64 mic did not sound very nice. Possible transformer, mic loading by decrease of input impedance. bass heaviness, undefined, boring sound. DC96: Vb=12V, Ia about 0. Rag=5M6, Ia becomes 7uA. Too much grit edge, not a great sound. Less gain at 5uA. At open grid, Vb=19V, Ia=4uA. Vb=25V, Ia=60uA, very bass heavy, grit edge, very low noise. Back to DC90: Vb=18V, Ia=40uA, why? Interminent heater problem? VP64 sound is nice but not as good as at 20mA. Possible cause bass heaviness by lower ra interaction with Lp of output transformer (anode resistance, primary inductane interaction). DF97 anode to screen grid: Vb=18V, Ia=5uA. Vb=25V, Ia=25u 62ua in one minute. Nice sound , very low noise, a bit bass heavy, no microphony, less bass heavy when begining at 20uA. Back to DC90: Vb=18V, Ia=40uA, Vb=25V, Ia+370uA, Vb=12V, Ia=2.6uA, intimate telephonic sound, still low noise but not perfect. Back to 1H4: Vb=12V, Ia=25uA, some microphony including bass one. very nice sound, a bit bass heavy but presence, 25uA sounds great on mic. Back to Pleiades Siemens AC151 VI open base: great sound, low noise, some flicker bass noise, when including WE 1:2 input transformer bass noise almost absent. A bit metalic but stangly smooth sound, too much gain, fraction of cost or power consumption.

How to operate electron tubes (vacuum tubes or electronic valves) at small anode potential (low voltage)

At your risk. Please take all safety precautions (for example left hand always in the back pocket, a fuse in series with a battery etc). When the cathode is heated it emmits electrons, so it becomes positive wrt grid or the grid negative wrt cathode. This intrinsic (negative) bias usually more than -1Volt (measured accurately with an extremely high impedance voltmeter) can cut off anode current at low anode potential. If we use a lower impedance voltmeter to measure this contact potential in fact we increase anode current by pulling up the negative grid by the positive cathode. A cathode resistor on the other hand will decrease this pull up bias. How can we make an electron tube operate at a low anode potential say 6V to 20V? Cathode is connected to ground. We can leave the grid floating (at space potential) and couple the input signal by a high quality capacitor. Depending on the mu (amplification factor) of the electron tube, if mu is say 10 then the penetration of the anode electric field above say 12V will make the grid less negative and the electron tube will operate with a healthy anode current. Advantages are extreme low noise by battery (in series with a protective fuse) operation, low temperature of electrodes leading to low secondary emission, low heater current, low radiation photoemmision from one electrode to another, low electron velocity therfore low secondary emmision by bombardment of an electrode by high velocity electrons. Less ionisation of residual gas etc. (see older euroelectron posts for references). For rediculusly low anode potential a high megohm pullup or Pleiades bias resistor can be used from anode or Vb to grid. Grid is still negative but less so. Input impedance of the electronic valve is decreased to say 100K. A great advantage of open grid is no grid current. Electron tube is so sensitive at such condition that it may become photosensistive too (gm of tube changind or modulated by light)! Further reading: Operating Features of the Audion _ E. h. Armstrong, Open-grid tubes in Low Level Amplifiers - Robert J. Meyer - Electronics, The Pleiades Bias - Euroelectron, History of low plate voltage electron tubes - euroelectron

How would a 2SJ74 (complimentary of 2SK170), microphone or RIAA or headphones amplifier sound?

One transistor headphone amplifier

At your risk, please take all known safety measures for your ears and headphones. How would a Pleiades Electra II amplifier sound with a Toshiba 2SK170 JFET? It seems ideal as it can give a 5mA quiesent current at 12V for class A operation (electrons flowing all the time). So music signal to gate through a potentiometer, amplified signal taken from drain by connecting 300 ohm headphones directly through battery plus and safety fuse.

On Music Making

For example, the song It Must Have Been Love - Roxette. Left hand thinks (single) bass notes, degrees or steps of a scale. Right hand adds harmony by thinking 1 or 3 or 5 or 7 or 9 or 11 or 13 above bass. Singer sings melody. That's all. The particular example song is written on C major scale. So the seven notes on our ususal music universe (do re mi fa sol la si) are all natural corresponding to the white keys on the music keyboard. Bass begins with C (tonic of the scale) so chord is C E G. Then bass chooses the subdominant of the scale which is F and chord becomes F A C. For best sound results we may use the least possible change of notes on the right hand (see principle of least change in music). So progression from bass F to Bass D is played F A C to F A D instead of D F A which sounds trivial or wrong. (from a discussion with Vicky). Further reading: Bach Bass Rules - Niedt, Bach

What if a cat refuses to eat

At your risk, this is not a medical advice. Aged Bebis, see older post, would vomit anything including water. Lampros' suggestion is that since cats seen near fishermen start eating a fresh fish begining from the head, since it's there were the nutrients are... Lampros advised on small fish. Cat ate immediately, wanted a bit more of this puree. At your risk, this is not a medical advice.

On creating a practical 25 volts DC source with four 4LR44 batteries

Attention: At your risk: Even 25 volts can kill. Please take all safety precausions including the left hand to the back pocket (this avoids an accidental electric current through the heart). Please also use a suitable fuse in series with a battery to avoid a fire or burn hazard. Today four 4LR44 6volt batteries were carefully inserted inside a Bulgin 2x AA battery holder, with left hand in back pocket and without touching any metal part with the right hand. Although batteries are about 1mm thinner than AA batteries, the length of four 4LR44 is the same as two AA batteries and it gloriously worked. It should be good fun to use such source of voltage for JfET 2SK170 pres, DC90, DC96, DAF96, DF97 etc electron tube Pleiades V6 1H4 type pres with Pleiades bias or even open grid? 1H4 has been found to be a miracle of low noise at 12V anode potential with grid at space potential.

Even 25 volts could kill

All safety precausions should be taken including the left hand in the back pocket to avoid accidental electric current circulation through the heart. First aids after an electric shock must be read, exercised. Even a few seconds delay can proove fatal. They are examples of persons surviving even after an 8 hour first aid breath support. A suitable fuse in series with a battery also helps preventing a fire hazard. Reference:Helliniki Radiophonia - Radio Karagianni Publications

Sorry for the typo, it should be William Walther version, Le Pacific RIAA Pre

According to truefi, twogoodears, blogspots this is the correct spelling. Mr. William Walther 2SK170 preamplifier, based on Jean Hiraga is impressive.