Go Back   Home > Forums > Blogs

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Old

My new speaker system

Posted 25th September 2010 at 12:03 AM by Sammumba

My job at the garage has been reduced to 4 days a week, which is great as it means I have an nice long weekend break. With all the free time I'm going to be working on my custom car stereo system.

My Nissan Micra probabaly doesn't have the best speaker system around.. Which is just as well because I'm going to upgrade it!!

I'm going to break open my old PC speaker sytsem

Click the image to open in full size.

And install it in my car. The sound qouality is amazing and I'm sure I'm going to get a lot of enjoyment out of it too.
diyAudio Member
Posted in Uncategorized
Views 604 Comments 0 Sammumba is offline
Old

Zen IV

Posted 13th September 2010 at 05:05 PM by DougL
Updated 15th September 2010 at 10:37 PM by DougL

Nelson has created a storm of interest with the Zen I/V.

I have a DAC that I can use this with, a K&K RAKK DAC Mk1.

Currently, it has a passive supply and a switchable shunt resistor.

So I am brainstorming on what it would take for an active Zen I/V with a shunt volume control, and both SE and Balanced outputs.

Basics: PCM1794 has differential outputs with 8 ma current output.
http://focus.ti.com/lit/ds/symlink/pcm1794.pdf
So I need 2 Zen I/V per channel.
At present, I am running a DCX2496 Digital crossover, so balanced outputs are a plus.

I am considering using the buffer from this post.
Since bipolar supplies are required for the I/V section, a buffer that does not require additional caps seems prudent.

For the volume control, either http://www.kandkaudio.com/linestage.html Shunt Stepped attenuator or a single LDR replacing the K&K unit.

Finally,...
diyAudio Member
Posted in My Projects
Views 1888 Comments 2 DougL is offline
Old

Blog Post the Second.

Posted 11th September 2010 at 07:29 PM by chris661

Well, here we are again, dear reader.

Today I received my Fostex FE126eN drivers from Dave, who has been very helpful in the whole process.

I have the cabinets (small, folded Voigt pipe, herehere. Partially made, as I needed the drivers in-hand to measure the cut-out required for the partition. Anyway, when I got the wood cut (asking specifically for 15mm MDF), they gave me a pile of 18mm MDF, with all the correct cuts. This would've made assembly a nightmare, so I phoned them, explained what had happened, and they sent someone over with the 15mm cuts. Sorted.

I decided to use the 18mm thick baffles as a baffle, give the drivers a run-in. Even after not very long, they sound bloomin' lovely. Sure, the treble's a little forward, and the bass needs significant eq (as you'd expect). But yeah, vocals are things are awesome to listen to. These are just far better than anything I've ever owned.

So, with the drivers bedding in nicely,...
Attached Thumbnails
Click image for larger version

Name:	100_1017.JPG
Views:	5093
Size:	89.7 KB
ID:	258   Click image for larger version

Name:	100_1018.JPG
Views:	5066
Size:	96.0 KB
ID:	259  
chris661's Avatar
diyAudio Member
Posted in Uncategorized
Views 747 Comments 0 chris661 is offline
Old

Need 150 to 200watts amplifier achematic

Posted 10th September 2010 at 12:44 PM by yoyomaster01

Hi to everyone!!!

I'm new i this site
I just want to ask for some pcb and schematic for a 200watts amplifier

Can P3A amplifier from ESP modified?
and add some more output tannies?
maybe 3 pairs?

I want to use MJE2955 and MJE3055 for the outputs.....

Any body?
diyAudio Member
Posted in Uncategorized
Views 782 Comments 1 yoyomaster01 is offline
Old

Common emitter amplifier design II

Posted 9th September 2010 at 07:27 PM by wakibaki

In the earlier post, basic common emitter amplifier design, I made reference to increasing the gain of the amplifier by bypassing the emitter resistor R[SIZE="1"]E[/SIZE].

In this case the gain referred to is the AC gain, which is the signal gain, and which is the gain we are primarily interested in with regard to audio amplifiers. The gain previously calculated was the DC gain, which was numerically identical to the AC gain, but since the amplifier was decoupled from the preceding stage with a capacitor, there was no DC applied to the transistor other than that provided by the bias network, which set the standing current to 1mA and the output voltage to 10V. DC gain and offset is important, because a decoupling cap can be avoided in some cases, but not here.

In the earlier post the gain was stated to be R[SIZE="1"]C[/SIZE]/R[SIZE="1"]E[/SIZE]. This was a simplification, and, more strictly the gain is R[SIZE="1"]C[/SIZE]/(R[SIZE="1"]E[/SIZE]...
Attached Thumbnails
Click image for larger version

Name:	common_emitter_4.jpg
Views:	1601
Size:	17.7 KB
ID:	255   Click image for larger version

Name:	common_emitter_5.jpg
Views:	1519
Size:	18.2 KB
ID:	256   Click image for larger version

Name:	common_emitter_6.jpg
Views:	2416
Size:	16.9 KB
ID:	257  
Banned
Posted in Uncategorized
Views 4581 Comments 0 wakibaki is offline
Old

Further education...

Posted 8th September 2010 at 01:35 PM by chris661

Well, this is a first. A blog.

Second day of college (6th form, etc), and all seems to be going well. The teacher seem reasonable enough, even though they do seem to like going back to basics. I expect that will change when the course is properly underway.

I'm taking AS level (A-level comes next year) Physics, Mathematics, Biology and Chemistry, with the intent to go into either a medical career, or to become an engineer of some kind (maybe work for B&W, Celestion or KEF........). Anyway.

What was I up to? Oh yes, changes that will undoubtedly take place. I really, sincerely hope that the teachers will stop telling everyone how much of a step up AS level is from GCSE, and actually do some teaching!! We were warned at the open evenings, in the introductory speech by the principal, by our secondary school teachers, even our parents, friends etc that have been through the experience.

Right. That's got that out of the way. Now...
chris661's Avatar
diyAudio Member
Posted in Uncategorized
Views 979 Comments 4 chris661 is offline
Old

100-160w mosfet amp

Posted 7th September 2010 at 07:30 PM by johnalexwarren

This is my first serious amp project. It uses the IRFP9240 & IRFP240 MOSFETs and delivers 100WRMS into 8Ω or 160WRMS into 4Ω at 0.1% THD.

Many thanks go to Edwin Paij @ AED (http://users.swing.be/edwinpaij/welcome.htm) for the design .

I have now gathered the majority of components and am currently active in the forum looking into PSU design...
diyAudio Member
Posted in Uncategorized
Views 1507 Comments 2 johnalexwarren is offline
Old

Turntable Technics SL-3 Wiring Diagram wanted

Posted 6th September 2010 at 03:45 PM by SirErik

Hey, I've got my Technics SL-3 turntable power supply damaged by a high voltage burst from the power station. I've found out that the transformator is damaged, but I haven't been able to find a new one. The number on it is SLT48DT 15E. I need to know either where to buy a new transformator or what specifications (voltage 240/? . .) this transformator has. Anyone who can help me solve this problem?
diyAudio Member
Posted in Uncategorized
Views 1681 Comments 0 SirErik is offline
Old

LME49830 based amp

Posted 4th September 2010 at 06:02 PM by alexcp (My DIY projects)
Updated 8th October 2012 at 10:26 AM by alexcp

This is an implementation of National's reference design for LME49830 with two matched pairs of 2SK1530+2SJ201 per channel. The PCBs were made using National's gerbers (thus National's logos). Sounds surpisingly good, but it has just been completed; I did not have a chance to listen to it carefully yet.

Update: I rebuilt the amp as a pair of monoblocks, each delivering healthy 200W into 8 ohms. It now looks tidier.

Update: the original Gerbers from National are nowhere to be found since national.com was merged into ti.com. Attached are the original archives downloaded from the national.com.
Attached Thumbnails
Click image for larger version

Name:	IMG_2067.jpg
Views:	1845
Size:	72.0 KB
ID:	251   Click image for larger version

Name:	IMG_2066.jpg
Views:	2426
Size:	65.9 KB
ID:	252   Click image for larger version

Name:	IMG_2068.jpg
Views:	1071
Size:	53.8 KB
ID:	253   Click image for larger version

Name:	IMG_2069.jpg
Views:	3127
Size:	56.7 KB
ID:	254  
Attached Files
File Type: zip LME49830_EF125WT1_Gerbers_Web.zip (133.8 KB, 368 views)
File Type: zip HP_PowerSupply_4B_Gebers_Web.zip (87.4 KB, 229 views)
alexcp's Avatar
diyAudio Member
Views 6161 Comments 5 alexcp is offline
Old

YAGC (Yet Another GainClone)

Posted 4th September 2010 at 05:58 PM by alexcp (My DIY projects)
Updated 5th September 2010 at 07:59 PM by alexcp

This was unavoidable, I guess. Dual mono LM3886 kit from ChipAmp.com with Avel Lindberg's transformers in a wonderfully compact enclosure from Design Build Listen. I liked the simplicity but not the sound. Why is everyone so excited with gainclones? IMHO, Papa's Zen V4 is not much more complicated to build (although no kit is available), but is so much more an interesting experience!
Attached Thumbnails
Click image for larger version

Name:	IMG_2058.jpg
Views:	806
Size:	41.0 KB
ID:	247   Click image for larger version

Name:	IMG_2059.jpg
Views:	699
Size:	41.5 KB
ID:	248   Click image for larger version

Name:	IMG_2060.jpg
Views:	822
Size:	63.0 KB
ID:	249   Click image for larger version

Name:	IMG_2061.jpg
Views:	1361
Size:	59.7 KB
ID:	250  
Attached Files
alexcp's Avatar
diyAudio Member
Views 2508 Comments 0 alexcp is offline
Hide this!Advertise here!

New To Site? Need Help?

All times are GMT. The time now is 12:20 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2