Tuesday 28 July 2015

My Journey of Audio Systems

My Journey of Audio Systems

I was born in 1971 in a typical middle class family in Lalbaug in Mumbai. My Grand Father was an interpreter in Small Cause Court in Mumbai. Though he lived till I become 9 years old, I can figure it out that he was a big music lover as we had Tabla & Harmonium back then. I faintly remember he is singing lullabies for me on harmonium. My journey of music I suppose started from those days.
My father was also a music lover but back then he just used to listen Hindi & Marathi film music. He worked as a Quality Control Inspector in an engineering company. He is still there but don’t know somehow his interest died down.I am going to document my journey of Music systems I have encountered with. I don’t claim that I have reached Nirvana with my present audio set ups but hope my journey will help others to choose the right one.
Philips Prestige Radio

This was a valve radio with 4 bands with a log scale and a needle. An indicator with a blue glow and a black band in it used to indicate the perfect tuning. The radio also had a PU option by which my father used to connect HMV Record Player. I remember listening to the sponsored programmes of Hindi Movies on Sundays and the “Chitralok” programme of hindi songs on “Vividh Bharati” Mumbai. I used to get fascinated by the signature tune the station was playing before the start of the station. I loosely remember a sponsored programme of Hindi Film “Kalicharan” with Amin Sayani’s golden voice. My Grandmother also used to play Marathi Songs on “Mumbai B” station. Life was so simple by then! The radio was replaced by a National Panasonic 2 in 1 in 1985. The radio bore its slow death due to my silly experiments.
HMV Record Player

I don’t remember the Model of the HMV Record Player but still remember that it was just a Turn Table having Tone Arm without Counterweight. The player didn’t had an amplifier. My dad used to connect it to the Philips Radio on PU Mode. Dad had a very good collection of Hindi & Marathi records and LPs. The player was quite small so we had to pick up the transparent cover for playing LPs. I still remember my dad giving away most of the records to his friend. I cried like anything that day but who will listen to a small kid. The player was with us for a long time. We had some records which I used to play on the player without amplifier. I still remember listening to the song “wada karle Sajana” of Movie “Hath Ki Safai”. It was a 45 RPM record but often used to play with 33.5 RPM & 78 RPM and listen to the song on slow and fast speed. I use to fiddle with that player till it died one day.
National Panasonic 2 in 1


Somewhere in 1982 our radio was replaced by this National Panasonic 2 in 1. This was bought from one of the shop selling Custom Seized Goods. We went to the shop auditioned different pieces and finally my Dad settled for a Mono 2 in 1. I wanted the stereo one but owing to the price difference of Rs.900/- he did not go for that. This surprised me as we had a Stereo Record Player. But maybe he was correct by then as besides outputting stereo sound the 2 in 1 carried only single speaker. The stereo sound was outputted through only earphone out. Meanwhile one of our neighbour got hold of Norge Sound System. That was my first introduction to Hi Fi sound. I have spent many evenings listening that. Back then my neighbours used to listen “OSIBISA”, “Boney-M” “MJ” and lots of Hindi Music Albums. I was so fascinated by the sound that whenever I used to hear the sound from our home, I used to rush to their house at odd hours too. That time only I decided that I am going to purchase a similar sound system with my first salary. Unfortunately my neighbours shifted elsewhere and then I also went for further studies to a Polytechnic for my Diploma Course. For the next three years nothing happened as I have to content with a Transistor Radio.
After completion of my studies I bought 2/3 locally made Amplifiers with speakers from Lamington Road  but frankly speaking they were not worth mentioning here.
Cosmic CO 100 Amp. + Cosmic COVOX 4500 Speakers + Cosmic Cassette Deck


As soon as I found a decent job I started saving for purchasing my dream sound system. One fine day in 1994 I landed up at Cosmic Radio Showroom in Andheri (East) for an audition. The sales person there was an old one of around 65 years of age happily gave me demos of all combinations, till I settled for CO 100 Amp. He suggested me to buy a smaller speaker than COVOX 4500 but at that time I was fascinated by the big 10” woofer so did not listen. Finally on one rainy day with the help of my friend loaded the consignment on a taxi and headed back to my home.
To my surprise my Dad didn’t like that. From that time onwards started my journey towards Hi Fi. I remember the whole booty cost me around Rs.15000/-. My monthly salary was just Rs.5000/- then. The amplifier churned out RMS 30 Watts @ 4 ohms per channel. The Speakers COVOX 4500 have big 10” Paper Cone Woofer with butyl surrounds, one 6” paper cone mid-range and a Tweeter. There is a separate enclosure for mid-range & tweeter and the other whole box is for sound waves from the Woofer. The Crossover has got massive coils. I am yet to figure out the electronics of the cross over. Though the specifications sheet read the frequency range 30 Hz to 30KHz, I never heard sound below may be 45 Hz. However since it was my first purchase I am very nostalgic about it. I still have got the Amplifier & Speakers. The sound was very good for a cassette player as the cassettes did not have the amount of detailing which the CDs have got. However when I purchased a CD player and attached to it the sound became bright. The mid-range and the tweeter became so annoying that I started to hate the system. I guess the amplifier was not giving enough power to the woofers. Meanwhile I purchased a used Cosmic Lab 5 amplifier to pair with these 17 Kg beasts but the condition never improved. Finally I got rid of the Lab 5 amplifier and then begun my quest for more bass down to almost 20 Hz atleast.
The amplifier has got black facia with matt finish, 4 inputs, and 2 sets of outputs, mono/stereo switch, loudness, and presence buttons with a filter for high frequencies.
The speakers have a very weird arrangement it seems that out of the pair one speaker is not the mirror image of the other that means I got two right hand speakers instead of one Left hand and one right hand. Could you believe? This thing also I noticed after so many years. What a naïve fellow I was back then. The arrangement is as shown below.
                                      
Can you believe what kind of imaging I used to get from these boxes? I often used to wonder why the soundstage is always drifting. It is because the placement was not proper. Imagine what kind of trouble I could have suffered all those years. But I must admit that the forum Hifivision educated me a lot about speakers, cross overs and terms related to audio world. Since last three years my interest in electronics started growing and I reached a level where I can able to draw circuit diagrams of small electronic components. With little patience and time my knowledge about electronics got better and I could figure out the Crossover of the speakers. The layout is as follows.

After figuring out about the mods to be done to tame the brightness of the speakers I tried below mentioned tricks
1.    I first lined the wall of the speakers with foam of ½ “ thick from inside. This was done as I was hearing some midrange frequencies from the woofer also.
2.    The mid-range & tweeter cabinet was also lined with the foam.
3.    Filled the midrange and tweeter cabinet with Recron fibres.
4.    With the help of some forum members from Hifivision decided to attach “L” pad to the tweeter.
5.    As the pots of smaller range were not available, I attached a preset of 1k in series. But then there was a new problem the high frequencies were forced to come out of midrange. To tame that I attached a 10k volume pot to the midrange but then there were two variables and it became very difficult to get “Phantom” image. The output from both the speakers were not the same and I have to constantly fiddle with the preset and the volume pot.
Finally I got frustrated and packed the speakers to the loft. That’s the time I understood that it is very difficult to modify an existing crossover. Now the Cosmic rig is taking rest on my loft.
Sony Ta-Ax44 Legato Linear Amplifier & Sony ss-S440 Speakers.



This was the amplifier my very dear friend was using. He was the second owner of the amp & speaker set up. He said that this was previously used in a movie hall in south Mumbai. The cosmetic condition of the amp and speaker was obviously very bad as they are more than 30 years old. As he got to know of my interest he offered me the amp along with the speaker for free. I tried to give him money but he didn’t take. One of the speaker has tweeter blown out, and both of them did not had grills. Looking at the condition I did not take the speakers at that time and settled only for the amplifier. The amp is very sweet sounding with a power rating of RMS 50 Watts per channel. All the buttons are of push type. The amp has got STK Chip for amplification and Legato Linear power supply. The chip has got an innovative way for cooling by way of fins. The amp was actually very roughly used and has got dry solder and loose connection problem. Every now and then the input cables need to be adjusted as one channel goes blank. The other problem is that one channel is around 20% weaker than the other channel. I did not figured out the problem initially, I was suspecting my Cosmic speakers but when I replaced them with other speakers the problem still remained. My friend then confirmed that while doing cleaning work some short circuit took place and the problem started from that time onwards. But these are the minor nitty gritties one has to live with used gear. I continued them using with the Cosmic Speakers.
In 2012 I came across to the forum Hifivision, from which I got to know that the amp sounds good with its matching Sony ss-S440 speakers. Again my quest grew up and I asked my friend regarding the availability of the speakers. Sadly I learnt that he has sent those to his native place. But as a true friend would do he arranged them to Mumbai by bus. I am so grateful to him! They were then attached to the amplifiers and started singing again. At that time I noticed that woofer of one box giving distorted sound at high volumes. The forum Hifivision came again to my rescue and learnt that since dust cap is not there for the speakers, it may have gone in to the spiders. The dismantling was done & I succeeded to remove some dust from the speaker driver. Since then the speakers have been paired with different amplifiers but every time passed the test with flying colours. Those are rare gems, don’t know why this kind of product is not there in production. Eventually I got all the six drivers as extra for Rs.3500/- from a forum member. So now I am a care free man as even if anything happens to the drivers the replacement is always there in my hand. Currently these are paired with a vintage Sony Receiver and almost daily I listen to it.
The speakers have 12” Paper Cone woofers, a paper cone midrange and a piezo electric tweeter. Since one tweeter is blown out I have replaced the midrange with one of my stock drivers which is happily doing the work of mid-range and tweeter together. The sound reproduction through these beasts is very nice and the bass frequencies are way more than enough to shake my house. I have remade the grills and have given some cosmetic look to the boxes.



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