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Modding - Where to start

readams

No longer wine tasting
Apologies if this has been covered elsewhere, but I did a search on where to start and drew a blank

Due to unforeseen circumstances, ill health and a relationship breakdown, I find myself unable to work for 6 months and the need to move from a house to a flat.

This means I need to downsize my system and also leaves me with a lot of time on my hands. Therefore I need a new hobby and I thought I would kill 2 birds with one stone and start looking at DIY HiFi.

I have a couple of confessions I need to make

1. I have no electronics experience. I consider myself vaguely intelligent and able to follow (relatively simple) instructions
2. I like Naim Audio - there I've said it, but I'm not evangelical. Things can be improved upon

I would like to start a project with an old CB pre-amp/power supply/power amp and mod them over a period of weeks in a bid to help me convalesce, and keep me sane. At the same time I could downsize my system but still keep an active interest in the hifi hobby.

Any ideas where to start? Websites, books etc. What Naim items should I be on the look out for? I'm not looking to spend lots of money, or make a profit but just keep my mind, and to a lesser extent my body, ticking over whilst I recover

TIA

Richard
 
Hi Richard.

What you could do is this: find a 32.5 preamp, snaps psu, and a 110 power amp (or upwards). The 32.5 is the best diy choice as the boards remove, mod, slot back in. The snaps is the best psu choice as its cheapest and mods can be simple (dual railing for eg) to medium difficulty (replacing the boards with ALWSR superregulators). Next best pre is a 42.5 (or better just go for a 62)- cheaper than a 32.5 and have much space in, but the downside is any mods need the whole motherboard removing to get at.

So preamps is the bodgers place and where to start/ snaps are good psu's to learn on, and can be made very good too/ naim power amps are in little need of any mods, so if I were you just recap one.

Then the next stage of diy would be making a simple psu from scratch. See www.Acoustica.XYZ for ideas of actual mods (*but forget silmic II's for feedback caps).

HTH Captain.
 
Hi Richard, My vote would be for a 42 or 62 preamp and a 140 or 160 power amp. (I'd look for a 62/160 personally)
Before starting with fancy regulators etc, i would re-cap the amps (bhc or jensen 4 pole caps are very good for the big psu caps) Read www.acoustica.org.uk for some good advice. Youtube has some good soldering videos, if you need them.
Once you've done that, look up Mr Tibbs split ov mod - its well worth the effort.
Must go to bed now. . . . .
 
Looks like i crossed posts with the Captain (why ar'nt you in bed?)
Good advice from Captain. I've heard a modded snaps, compared to my modded hicap and could'nt tell the difference.
 
Apologies if this has been covered elsewhere, but I did a search on where to start and drew a blank.

Due to unforeseen circumstances, ill health and a relationship breakdown, I find myself unable to work for 6 months and need to move from a house to a flat.

This means I need to downsize my system and also leaves me with a lot of time on my hands. Therefore I need a new hobby and I thought I would kill 2 birds with one stone and start looking at DIY HiFi.

Richard

Hi Richard,

DIY hifi is the way to go IMO! :D You didn't say whether you actually already own any Naim kit (which is why you like it?) but another option - apart from modding old Naim CB gear - is to buy AKSA kits (http://www.aksaonline.com/).

I sold all my CB Naim gear (2 x 250s, 42, Hi-Cap and a 160) about 5 years ago when I took one of my 250s over to the designer's place, to compare against an AKSA (luckily, he lived in the same city as me! :) ). The AKSA blew it away - and since then there have been several upgrades which make them sound even better! :)

The instructions are excellent and the after-sales support is phenomenal ... so if you say you can follow good instructions, you won't have any problems. You can choose several options in terms of construction - either buy ready-made amp modules and PS PCBs, so you just have to put these into a case and add the wiring, or buy the kits ... so you have to solder the components to the PCBs as well.

Whichever you do, I suggest you need 2 soldering irons ... a temperature-controlled iron like a Hako 936 and a "hot" one for stuff like spkr binding posts.

Regards,

Andy
 
Richard, I got into DIY hi-fi mainly because of long-term health problems that left me looking for something to do, and without the money to go out and buy better hi-fi.

May I humbly suggest that you spend some time on Decibel Dungeon
http://www.decdun.me.uk where I have gone to some lengths to help people get started in this marvellous hobby! ;)
 
Richard,

Don't overlook PFM! There are years of detailed discussions on all sorts of things to be searched here in the DIY room; and the Reference area also has some helpful DIY related links posted by Andrew Weekes and others (set Display options to 'from the beginning' for these to show up)
 
Hi Richard,

Diy hifi and Naim is imho a very good choice of hobby! If you're modding Naim you really should look at the descriptions on www.acoustica.org.uk

Lots of good naim preamp mods described in detail, also diy powersupplies and specific component suggestions for recapping amps and psus. Very good!

/Magnus
 
Captain, I've also been searching for speakers. I love my kans but would like something that works better at lower volumes. I've been looking at Jordan designs on diyaudio. The jim griffin jordans look pretty good but i still cant make my mind up.

My ideal speaker would be the lovely omni-directional mid/treble of shahinian arcs, the bass of a good quality, sealed box, active subwoofer and the sensitivity of a full range driver. Oh well, i can dream. . . .
 
Just remembered, if you do buy a Snaps, i dont think can do the split ov mod but i thought the biggest gain (very large increase in dynamics) was replacing the snaic with a nice chunky, low resistance cable (13 amp flexible mains cable is fine). Then stick a bhc t-net 4 pole cap in it (you can buy one from Patrick dixon) . That would make a killer Psu for relatively little cost.
 
You won't go far wrong with an Air gutar-iste preamp. You can etch a board pretty easily. There aren't many parts - say compared to a Starfish. It won't break the bank and it will sound a whole lot better than any modded 32.5. Some people have sold some very expensive preamps after having built an Air Guitariste.

Teddyregs provide a great and simple power supply for it. Way better than a Snaps IMHO.
 
Why not buy the items that have been suggested and rather than trying to alter them, just service them , replacing any parts that might have become damaged, dried out or worn with age and use. ( electrolytic Caps, Volume pots , etc). Once the Units are back up to at least their original spec use them for a while and then see if there is anything so wrong with the sound, or operation of the unit that you don't like, then see if there are any specific mods that address these deficiancies, for example;
I modified my Rotel RQ970BX phono stage because i changed cartridges to one that i'd wanted to try for a few years but then found that the low output of my new cart and the low(ish) sensitivity & gain of the RQ970 didn't really suit each other. I found a mod on the internet that addressed these problems and felt that the unit as a whole not only improved my new cart but others that i tried too.

My new phono stage seems to work perfectly with my current cart and so I've got no intention of meddling with it, although I will try to fix it if it actualy breaks down.

Before you start modding something you need to know why you are doing it and also confirm that the equipemnt in its 'stock' (but fully serviced state) doesn't sound so bad after all, especially if it is an older unit.
 
Or you could build an AD815 preamp. Some people have stopped using the air guitar'ist pre because of this amp.
It's not difficult to turn a 62 into a air guitar'ish (note i said 'ish) clone and you have the benefit of being able to do it one step at a time. So you get to know how all the individual mods affect the sound.
 
Thanks, it's a pleasure to share the knowledge that was obviously shared with me in the first place! Kinda makes the hobby even more fun! ;)
 
Many thanks for all your replies esp the 2 excellent websites mentioned

Sid and Coke, I think your idea is a good one thank-you. I've got and old CB 250 that has never been serviced. I think I'll start with that and look out for a s/h 32.5 and SNAPS and have a go at servicing them.

Cheers

Richard
 
Richard,

For starters, you need to read this.
I mean really read the thing. All the pages. Even the footnotes. Its no hardship I promise.
Its a piece about building, modding and tweaking by my favourite audio writer.
Informative and highly entertaining.
Its also the only diy article I've read on Stereophile.
This was way back when they were printed in a handy, smaller-than-Readers'-Digest format that won't slip slowly off the cistern in the loo.

Fatmarley mentioned the AD815.
The star of wacky Corey's project was also a device designed for video.
Here's a snippet..

These devices are often called on to drive ultra-high-frequency video signals over great lengths of coax in 75 ohm circuits, and needless to say, a good buffer wets its pants with laughter at the thought of carrying mere audio signals; to call these devices "overkill" for audio would be an understatement!
 


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