*** The DIY Audio Thread ***

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Would you recommend the stereo kit over the dual mono? I was originally going to buy all the components myself for a LM3875 and either build on strip board or design my own PCB layout but I have a feeling it would be more expensive. Might go for one of these LM3886 kits with a power supply kit and get myself a really nice enclosure with the money I would save.
 
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Have you done much in the way of case work damian? I had a look at the German site you highlighted on the first page, and combined with a modushop case it could look really nice! Pricey though...

None, im not even buying the cases until all construction work of every piece of the hifi unit is done includes the pre amp which the PCB is on order from somewhere in Europe, i think its called the soap mkII then ineed the gubbins to go into it. I then need to build the new amp which at the moment looks lik eit going to be a lm3886 bridged arraingmant. Need to get Trafos for all above and mesure up total size as all trafos wll be isolated in a single case, then i need to buy all connections and fixtures and fittings for the project. Then and only then can i go ahead and order the cases so we are talking 6-8 months for that. After that i need to have all the back and front plates made up and engraved so more money which no doubt ill take up another 2 to 3 months so im quite away from cases yet.

Would you recommend the stereo kit over the dual mono? I was originally going to buy all the components myself for a LM3875 and either build on strip board or design my own PCB layout but I have a feeling it would be more expensive. Might go for one of these LM3886 kits with a power supply kit and get myself a really nice enclosure with the money I would save.

first time round a kit is definatly the easier option, the psu board and gubbins come with the kit. as for dual mono or stereo, dual mono is supposed to be more powerfull, with better bass etc,i cant really comments as ive never looked into it but as you have bought the subject up i may just investigate tonight and see what benefits a dual monoblock would provide!
 
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yes, they do. Different better or different worse.

You can buy really expensive 'passive preamps' which are essentially expensive volume pots.
 
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Damian, nice pillar drill! I want one!

What's an acceptable DC offset for a pair of headphones? I've got 18mV on one of my outputs from the cheap DAC. I could easily add a coupling cap, but I'd rather not if I can get away with it.
 
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Seems well within tolerance levels, i dont see any point in extra gubbins for some thing trivial like that. 20 is about maximum for a decent headphone amp so your ok, more is fine but 20 is a reasonable number to aim for.
 
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Soldato
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Follow up.

Well true to my word i done a little digging last night on the subject of monoblocks VS stereo. Turns out that monoblock means that the whole of each channel in the amp is handled as a seperate amplifier, they have separate power supply's, separate grounds and a true mono block has separate chassis for each. This in mind the best compromise is instead of two trafos, two psu's and two amp channels completely separate your better off with two power supplys delivering the same capacitance to each channel as the one would usually provide for two resulting in punchier and tighter bass but with a single large trafo supplying both. A larger trafo will be less expensive and i think im correct in my understanding of what they were saying that a single large trafo performs better than two smaller ones.

seperate chassis are neither hear nor there and only down to preference or high end "esq" aspirations for aesthetics and real world difference is minimal at best, infact i may be incorrect but im sure chipamp or "gainclone" amps perform better with a central ground for both amps, i know a lot of issues seem to be cured with a central earth point.
As for which is better, on paper the monoblock should be the better choice but ive never listened to one so i cant comment with advise for someone looking to purchase one. The only instance i could find of someone doing a side by side test in my brief search was in a sub so nto really gonna help for a complete listning experience.
 
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Soldato
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I am doing an order from vt4c.com. The shipping is quite expensive. Does anyone want to share an order with me?

No not atm got lal my bits for upcoming builds, excpet cable and sheething for my SR-60 and ksc075 re-cables.

vt4c are great, english not that great, but I asked him/them to mark down my package as gift and $20 to get around the customs charges. I bought 6 pairs of the solid silver cmc rca sockets and lots of cotton.
 
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Damian666.

I'm looking for the parts to upgrade my DAC like the LAMPUCERA. I can find the Oscon caps at Farnel but not the Winma. Could you send a link please. Thanks.

Edit.
Forget that, i see you went for the Tat's. Where can i get them and how much please.
 
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Associate
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1 valve rectified powersupply (260v regulated) for the heaphone amp.

img9311hu1.jpg
 

Kol

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All thse items look awesome. I'm definitely going to make a usb DAC and an amp. I just need help in choosing what to order and from where. Then I could order it tonight.
 
Associate
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alien dac: glassjar audio (get Jeff to pre solder the chip - only $6)

amp: valve go for a SohaII in a couple of weeks, or the milletmax (again, contact jeff at glass jar, he will do a kit). IF you want solid state go for for the ckIII.

So much cheaper to get the kits from glassjar.

If you havent done any soldering the alien will be too hard, and the first amp should be a cmoy. then tackle something bigger. apologies if you have.
 

Kol

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No need for the apologies - that's good advice! I'll check it out!

Unless someone has built one already which they want to depart with in MM ;)

When you say get Jeff to solder the chip - would that be this one - http://www.glassjaraudio.com/product.sc?categoryId=4&productId=18 pre soldered it looks like?

This for the headphone amp http://www.glassjaraudio.com/product.sc?categoryId=3&productId=8 ?

Also - once I've tackled the SOHa, then attempted a DAC., I'd like to attempt a stereo amp - suggestions on that too would be helpful :)
 
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Associate
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the soha is a reasonable first build, but you are dealing with mains voltage. I would still advise a cmoy for a first builld. Mess something up on a soha and it will burn several components.
 

Kol

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the soha is a reasonable first build, but you are dealing with mains voltage. I would still advise a cmoy for a first builld. Mess something up on a soha and it will burn several components.

Good thinking. I might start with a cmoy then!

I have an amp for sale, but no dac i'm afraid.

What amp are you selling? I would consider making one - just because it would be fun to be using something I made rather than my Cambridge Audio A1 :/
 
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