where to get electronic components to customise my preamp.

[saibuster]

hey all.

Im looking to cutomise and replace some parts in my MEC preamp.

the parts im looking for are TL072 and TL074 to replace the TL062 and TL064.

Does anyone have any idea where i can find them online? everywhere i look it seems as if i'll have to buy a bulk of them, or spend more than 100£ on an order.
I only need one of each.

If the internet is not the right place, maybe somewhere around central london?

thanks
Ito.

[bremen]

[quote name='saibuster' post='313862' date='Oct 24 2008, 03:01 PM']hey all.

Im looking to cutomise and replace some parts in my MEC preamp.

the parts im looking for are TL072 and TL074 to replace the TL062 and TL064.

Does anyone have any idea where i can find them online? everywhere i look it seems as if i'll have to buy a bulk of them, or spend more than 100£ on an order.
I only need one of each.

If the internet is not the right place, maybe somewhere around central london?

thanks
Ito.[/quote]

Maplin Electronics have shops in various parts of London, they'll have them. Or Cricklewood Electronics.

[saibuster]

great thanks! got it from Cricklewood Electronics.

Now for the next question, as i have zero knowledge in electronics where can i get them replaced?
it seems like a very easy job for a professional.

[bremen]

[quote name='saibuster' post='313901' date='Oct 24 2008, 03:45 PM']great thanks! got it from Cricklewood Electronics.

Now for the next question, as i have zero knowledge in electronics where can i get them replaced?
it seems like a very easy job for a professional.[/quote]

I'll do it for the price of a pint if you post the bits to me (I'm assuming the preamp is an onboard preamp, not something that'd cost $$$ to post). PM me if you're interested.

[thepurpleblob]

[quote name='saibuster' post='313862' date='Oct 24 2008, 03:01 PM']hey all.

Im looking to cutomise and replace some parts in my MEC preamp.

the parts im looking for are TL072 and TL074 to replace the TL062 and TL064.

Does anyone have any idea where i can find them online? everywhere i look it seems as if i'll have to buy a bulk of them, or spend more than 100£ on an order.
I only need one of each.

If the internet is not the right place, maybe somewhere around central london?

thanks
Ito.[/quote]

My first question is who told you changing those chips would make any difference? Without any accompanying circuit changes to affect (say) the gain etc. you're not going to notice a thing.

Edited October 25, 2008 by thepurpleblob

[saibuster]

[quote name='thepurpleblob' post='314357' date='Oct 25 2008, 09:21 AM']My first question is who told you changing those chips would make any difference? Without any accompanying circuit changes to affect (say) the gain etc. you're not going to notice a thing.[/quote]


I've researched into it an realised that the stock electronics that you get with the default MEC preamp are aimed into preserving battery life.
these two chips are basically the amplifiers (opamp) of the preamp, changing them can have a dramatic effect.
Since i dont mind switching a battery every three month, the sonic benefit is quite noticeable.
(i recycle all my batteries and use rechargeable ones when possible )

Here is what the guys over at MEC had to say:

[color="#000080"]you have to exchange the TL 062 (it is the small one) to a TL 072 and the
TL 064 (it is the big one) to a TL 074 and if you do this, the noice goes
done from 30 nV to arround 16 nV..
[/color]

If you ever had any experience with MEC (9v) preamps you'll know that they can get quite noisy, especaly when you dial up the treble.

30 nV to 16nV is half the noise to signal ratio.

hope it answers your question.

[thepurpleblob]

[quote name='saibuster' post='314609' date='Oct 25 2008, 05:43 PM']I've researched into it an realised that the stock electronics that you get with the default MEC preamp are aimed into preserving battery life.
these two chips are basically the amplifiers (opamp) of the preamp, changing them can have a dramatic effect.
Since i dont mind switching a battery every three month, the sonic benefit is quite noticeable.
(i recycle all my batteries and use rechargeable ones when possible )

Here is what the guys over at MEC had to say:

[color="#000080"]you have to exchange the TL 062 (it is the small one) to a TL 072 and the
TL 064 (it is the big one) to a TL 074 and if you do this, the noice goes
done from 30 nV to arround 16 nV..
[/color]

If you ever had any experience with MEC (9v) preamps you'll know that they can get quite noisy, especaly when you dial up the treble.

30 nV to 16nV is half the noise to signal ratio.

hope it answers your question.[/quote]

30nV to 16nV!! nV!!! You know what a nanovolt is? This sounds crazy to me. I'm prepared to be wrong, but you can't hear nanovolts of noise.

EDIT:
Thinking some more... I'd be even more surprised if the preamp was the noisiest part of the signal chain. I'm really intrigued to find out what happens when you change these chips now

Edited October 25, 2008 by thepurpleblob

[saibuster]

[quote name='thepurpleblob' post='314611' date='Oct 25 2008, 05:47 PM']30nV to 16nV!! nV!!! You know what a nanovolt is? This sounds crazy to me. I'm prepared to be wrong, but you can't hear nanovolts of noise.[/quote]

I know it 16nv seems to be something you wont notice, but everywhere i read people are raving about the difference they achieved by switching to more quality opamps.

here is an interesting discussion about it:

[url="http://www.tomshardware.co.uk/forum/39648-32-ad822-good-tl062-replacement"]http://www.tomshardware.co.uk/forum/39648-...062-replacement[/url]

i guess there is nothing to loose so im willing to experiment. i'll post my experience here once its done.

[escholl]

the noise figure is actually given in nV/sqrt(Hz), or nV per square root of the frequency.

there are, however, likely to be other factors that will attribute to a better sound, the TL0 series are pretty good so i wouldn't be surprised if the sound does improve somewhat.