External DSP Using Pioneer KEH-P9750

The Pioneer KEH-P9750 is a hi-end car cassette player built around 90's. The audio features in this head unit is beyond of it's era. It has built-in sound processor, 6 channel time alignment, 13 band equalizer and auto EQ by using the mic for the sound adjustment. It also included internal power amplifier rated 4 x 45 watt which enough for simple car audio setup.

I will not using the cassette player on this Pioneer KEH-P9750. It is outdated for today media standard. I also never play music from the cassette anymore.

This head unit is great. I don't want to waste this head unit consider so many advance audio features on it. That is why I will using this Pioneer KEH-P9750 on my car as an external DSP to adjust and tailored the overall sound.

Tripath TK2050 Amplifier Updates

It is been a while since I built this Tripath TK2050 amplifier and I using this amplifier ever since.  As usual, I still curious with my own built and sometimes I need to open it up again. It is sometimes relaxing for me to see my own built, but others than that, I always try to find any parts need to be upgrade.

 

Audio Technica ATH-M50x Limited Edition With The CMOY Headphone Amplifier

Audio Technica is the most well known brand for their headphones. Most of their headphones are also use by professional application related to audio. This is very iconic brand and especially for the ATH-M50x, this good looking headphone is really catch my attention.

In this weekend, I have a chance to test the ATH-M50x Limited Edition version. I will connect it with my new build LME49720NA CMOY headphone amplifier.

DIY LME49720NA Portable CMOY Headphone Amplifier

It was on Friday and heavy rain outside.

As usual in that condition, the traffic jam from my office to home will be very high. So I decided to go to my favorite electronic parts shop nearby instead directly went home.

Firstly, I don't have any plan to buy anything. I just came there to have a little chat with the owner. But things changes when I saw this high quality PCB of the headphones amplifier. I certainly want to make one for myself.

Bookshelf Speaker Vifa TG9 Vs. Visaton SC13

I wish you have following this blog and you will aware that I am using a pair of DIY small full range speaker in my audio setup. This speaker is using a single driver from Vifa TG9. It is a 3.5 inch full range driver which the sound is surprisingly wonderful. You can read my review of Vifa TG9 here.

As always, DIY audio is a journey. I wish I could have a bigger driver for the single driver full range speakers as the replacement for my current speaker using Vifa TG9. Naturally the bigger driver should have better bass response. That is why, from few days before, I really put my interest on this Visaton SC13, a 5 inch full range driver that I think it could perform really well for the full-range speaker project.

So how good is this Visaton SC13 compare to the Vifa TG9? I will reveal in this post.

Nakamichi PA-100 The Smallest Car Audio Amplifier

I make this post after I cleaned my storage room last weekend.

I found this unique small car amplifier. It is Nakamichi PA-100. This finding is surprising me since I don't know that I still keep this old school amplifier until now.

If I don't mistaken, I bought this small amplifier in the second hand condition around late 90's and I have no idea where is it now until I found it.

 

LM1875 Gainclone Amplifier With First Watt B1 Buffer Pre-amplifier

I like building amplifier because it is fun. Anyway, we are doing this hobby because it is all fun. But what I am trying to say is, I can planning something that I want to make for the next project and when the result is beyond my expectation, this is the magnet to dive into this hobby deeper.

This is happens when I plan to combine the First Watt B1 buffer pre-amp with the Gainclone LM1875 amplifier. I like sound of the LM1875 amplifier and I also like the idea behind the First Watt B1 buffer pre-amplifier. So how if they are combine?

The Old Logo LM1875 National Semiconductor

As you can see from my previous post and far before I create this blog, I have built many Gainclone amplifier using either LM3875, LM1875 or LM3886. The sound characteristic from each IC is all different. Let take the example LM3875 or LM3886 that perform more dynamic and open sound stage. Those IC's are also the latest production comparing with the LM1875. Speaking about the LM1875, this is the ancient IC from National Semiconductor. This LM1875 sound characteristic are so much different with its brother. It sound more warm and mid-centric amplifier. I also aware that this LM1875 is one of favorite IC. It has been around very long time before this Gainclone amplifier become popular like today.

If I took the different production batch of this LM1875, I found different characteristic especially between the old production and the newer one. This is very interesting and I will talk about it in this post.

DIY LM3886 Gainclone Car Amplifier

I am happy with the sound come from Gainclone amplifier. I using it in my home audio system and I wondering if I can have it on my car as well. I think it would be a lovely idea. What I knew that Gramond car audio, a brand, using the same Gainclone amplifier circuit on their amplifier line up. Gramond sell this car amplifier for around US$350 each. It is a car Gainclone amplifier with tone control.

I think, in this post,  I will make one for myself. I want pure amplification from the Gainclone amplifier without any pre-amplifier or tone control. So here it is.

Single Driver Vifa TG9 Full-range Speaker

I recall my memory from the beginning I jump in this audio hobbies which I should follow to the general audio rules of thumb. Especially for the speaker, the best sound is always from multi-way speakers system. Then if the bass is not strong enough, so adding a sub-woofer or two will improve the low frequency gain. The music can be fine tune as the listener preference with tone control.

I follow this rules for years and at the end it is very complicated. I cannot enjoy the music because I am too busy dial the tone control and adjusting the sub-woofer level. The music is mix with additional noise and dirty from the unnecessary equipment in the signal path. No matters how many times I dial the tone control or the sub-woofer setting, the music never presenting well to my ears.

Until one day, I was thinking about changing my audio system in a simple way. This only the source, it is a CD player, a passive volume control and power amplifier. There is nothing else.

The speaker also very simple, with no cross-over at all. The goal is this system should deliver the sound quality that I wish for. Then this single driver full range speaker project comes in mind.

Tripath TK2050 Amplifier Kit Review (Part 3)

This is the part 3 of this Tripath TK2050 Class D amplifier built. I want to customize the amplifier casing and it is require the high precision tools which I prefer go to the professional workshop. This amplifier appearance will become my priority. I wish the casing result will be as clean and precise as possible compares if I do it by myself using hand tools. This professional workshop will do the milling for the input and output amplifier terminal.

 

Tripath TK2050 Amplifier Kit Review (Part 2)

This part 2 is continue from the Part 1 here.

After my office hour yesterday, I had a chance to visit my favorite component audio store. I bought several components to continuing this Tripath amplifier project. As you can see this Tripath amplifier projcet will be very interesting because the components that I choose for this project is so much better and expensive than the price of the kit itself.

 

DIY Smallest LM1875 Gainclone Amplifier

In this post, I will share the building process of the smallest LM1875 Gainclone amplifier. This is including the toroidal transformer in one casing. To make this amplifier looks simple inside, I will not using any PCB, instead all components connection is done by point-to-point wiring. Let's take a look shall we?!

 

Tripath TK2050 Amplifier Kit Review (Part 1)

The Tripath amplifier is IC manufacture that specialized making high efficiency amplifier. Tripath patent it with the name of class-T amplifier. It is basically a PWM digital processing that found in most class D amplifier, although they claimed it is better.

Because this Tripath is an IC based amplifier which come in finish board, this easily become the new star in DIY audio. It is simple to build and have a good the sound quality. This Tripath amplifier only supply with single rail DC, commonly only with 12 volt. The one I have right now is Tripath TK2050 amplifier which cost me only US$25 in this complete board.

 

What Gainclone Amplifier's IC should I choose?

When you plan to build this Gainclone amplifier by your own, especially if this is the first time build, you might asking the question about of what kind IC's for this Gainclone amplifier should I use? This is a normal question and I will try to help you by describing the sound quality from each IC.

DIY Gainclone Amplifier Using B&O Toroidal Transformer

The result from making an electronic project is determined by how good the components you put them in. You can build with the cheapest components and the result mostly unsatisfying. Especially for the major components, one of them is the power transformer, I prefer using the high grade transformer that built for audio use.

Like in this Gainclone amplifier project, I will using the special hi-end encapsulate toroidal transformer salvage from the old Bang & Olufsen power amplifier. This toroidal transformer is very slim and of course it is in used condition. But for the transformer, I don't think they have the short lifespan. Maybe it can be use forever as long as it is working within it's limit.

This Gainclone amplifier is popular built for beginner because it made from the National Semiconductor IC. The Gaincard amplifier which is the original product of 47 labs using the same IC and it sound great based on the reviews I've read. This amplifier is simple, only using 9 components per channel and they sell it around US$3,000. It is very expensive but no wonder for the price of Japan handmade product.

Because of this Gaincard amplifier story, then someone on the internet has open the original Gaincard and inspect the components inside it. The clone is now become very popular since it is easy to make. They called it a Gainclone amplifier. A clone from the original Gaincard amplifier.

The IC use in this Gainclone amplifier is LM3875 that cost me US$7 each. We need 2 for stereo of course. The total cost to make this Gainclone amplifier is depends on how much you want to spend with the others components. Mostly the estimate cost in building this Gainclone amplifier, using a nice amplifier casing, a good toroidal transformer like this, you might spent at least US$200.

 
Previously I already have another Gainclone amplifier, but I could not resist to built another one. Especially when I have this 160 VA special toroidal transformer taken from the Bang & Olufsen amplifier. This toroidal is heavy with sealed encapsulated cover to eliminate unwanted noise escape from this transformer. As you can see from the photo, the height of this toroidal transformer is quite shallow. It is suitable for the small amplifier casing like I am using here.

To be honest, my first amplifier layout didn't work really well. What I learnt from this built is I didn't use enough capacitor for DC filter and the position of rectifier diodes very close to IC's. This cause the interfere from the rectifier to the power amplifier IC's.

Although the first layout is the most simple layout of this Gainclone amplifier that I've ever made, but I should re-work all the components again just because of the hum noise from the speakers when this amplifier idling.

The second layout is more complex. I taken away the rectifier far from the IC's. They are now place behind the toroidal transformer. This method is 100% works well and completely silent when idling.

This Gainclone amplifier is all finish. Then I order to my friend, the front panel that he made it using Oak wood. The finish is very nice. This panel makes this Gainclone amplifier looks more elegance.

Anyway, should I mention how is the sound quality?

This LM3887 Gainclone amplifier sound very dynamic. The sound-stage presentation is wide. The details are rich, especially on mid-range to treble. The vocals, it is not too forward, also not too laid back. It is right in the center of the instruments. The vocal is not warm but not analytical as well. It is just balance, it is a natural sound presentation.

Spending this little amount to build the amplifier like this, with this high quality sound is worth so much.

Disclaimer: Any statement and photos in this article are not allowed to copy or publish without written permission from the writer. Any injury or loss from following tips in this article is not under writer responsibility.

DIY First Watt Nelson Pass B1 Buffer Pre-amplifier

If you into this DIY audio for quite long time, you should already know the audio guru: Nelson Pass with his First Watt products. His idea and concept in making the amplifier is simplicity. All of his amplifier are made by using only few FET transistors. The most important thing about Nelson Pass is he kind enough to shares all his design to this DIY audio community, so you can build one and having the same experience like he did with his design.

Nelson Pass also designing pre-amplifier with the same concept. In this post I will share the B1 buffer pre-amplifier building process. The main function for this buffer pre-amplifier is to match the impedance between input and output. So the next equipment, such as the amplifier can be work optimally.

This B1 buffer pre-amplifier is consist pairs of SK170 FET transistor per channel. It is simple to build without any PCB, or just with a point-to-point connection.

Best Article From The Stereophile Magazine Issued On December 1996

One article from the Stereophile magazine here is really taken me about what I find in this audio hobby. Issued on December 1996, it is on page 3 which mostly filled about the writer's perspective of the this audio industry. This article is written by Robert Harley for his observation about common finding in audio. It is quite funny to read it since I personally have meet the same experience like he written there. He is describing the true condition from most all audiophile facing with their system and with their society.

Sony Playstation SCPH-1001 My Reference CD player

I can predict that most audiophile have ever read the Stereophile magazine. This is the famous audio magazine and for me, this magazine is become my holy bible in audio since the first time I am focusing into it.

I still remember one quoted from the Stereophile magazine is like this:

"if the source is bad, nothing on the downstream can make it better"

It is so true indeed. I remember the first time my friend borrowing me his Sony Walkman portable CD player very long time ago, perhaps the series is D-55, then replacing my cassette deck to this CD player is just elevate my poor audio system to become so much better. The next month I should return it back and my audio system is back to crap sounding again.

By that experience, I can tell how good your whole system is mostly determined by what source you are using in it. At that time, the new CD player are not affordable for me. I keep looking the great CD player in used condition for so long.

Then this is what makes me choose the Sony Playstation SCPH-1001 as my reference CD player.

 

Welcome To THE ORRONOCO AUDIO DIY

Welcome to my blog.

A brief about myself, since I was a little kid. I often get caught by my parent dissemble their electronic stuff without their permission. From the simple torch light, a wireless telephone, and also their mini stereo system, I try to figure out on how they work. Of course I got punishment by doing that, but it is the pinnacle from me to start into this hobby.

Move forward to my junior high-school, I start making a simple electronic project that sell in a kit. This electronic kit can be assembly without soldering needed and they are variate from the simple flip-flop LED, a sirens sound, and a single transistor MW radio that operate using a 9 volt battery. At that time, this kit quite popular for beginner like me. They sell it on the books store and no wonder, in the 90's, the books store is one of popular shop. After some time I start to train myself to use the soldering iron, then I made a simple power supply as my first DIY electronic project.

From that time, my electronic project are expand based on PCB commercially available and I start to make an amplifier. I still remember how happy I am when my first amplifier start to work with just a simple speaker using a plastic cup as enclosure and a portable cassette player. From that, I start get into this hobby deeper and deeper.

This blog is made because my love to the audio stuff. I will shares, review, or post anything related to audio. This blog is my personal documentation about what I did on this audio project. You can use the contents in this blog as your DIY inspiration, or you can just treat this blog as an entertainment only.

The name ORRONOCO is has no meaning at all. It is just a name. It is across my mind when create this Blogger account.

The photo bellow is one of my DIY amplifier that I build without any PCB. Instead it is made by point-to-point for each components. The reason for this point-to-point built is has another story. I always waiting for commercial available PCB to make the electronic project. This has so much limitation such as the PCB size which always bigger than my expectation, the schematic and design that not suit to my preference, or I just want to build based my own design but I simply can't make any PCB. So one day I saw the internal of a vacuum tube amplifier that built based on this point-to-point connection. I asked myself, why I don't do the same for solid-state? This will be my new challenge to build something that I wish for without expecting from others design PCB. That's I think become my new journey to this new DIY audio world.

Back to this amplifier, it is a dual mono LM1875 Gainclone amplifier. It sound so good and it also look very beautiful. I made it several years ago and unfortunately the building process is not documented at that time. Hopefully with this blog, I will never missed to documenting the building process like this anymore.

Disclaimer: Any statement and photos in this article are not allowed to copy or publish without written permission from the writer. Any injury or loss from following tips in this article is not under writer responsibility.