DAC builders/modders.I need help/data.

fbm211

I want to upgrade/replace the opamp in my DAC from a NE5532 to a AD825 type 2 Dual AD825.Kyle at audio reference mods wants 175.00 to do it.The opamp is 38.50 (John Hillig/Musical design thinks thats 50.00 too much.)Maybe with some info and help from polkie modders I can do it myself and save some $$$ to spend on other upgrades John can do.Like replace all the power supply caps,Pertinent diods to custom RAM rectifiers, better input/output connectors and maybe a superclock upgrade too.Can anyone here point me to some how to reference guides or books???? Thanks.

Systems

What DAC are you modding and do you have a schematic?
I think the AD825 is only available in surface mount SOIC package,is the 5532 SMT aswell or a standard DIP.Some sort of specialized adaptor board will be needed to get two 825's into the DIP socket.

fbm211

Adcom GDA-600.Audio reference mods states the AD825 replaces the NE5532. http://www.referenceaudiomods.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=RAM&Category_Code=OPAMPS

Systems

fbm211 wrote: »

http://www.referenceaudiomods.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=RAM&Category_Code=OPAMPS

Ah yes that is what I meant,they have designed an adaptor PC board that will allow the 2 SOIC 825's to fit in the DIP foot print of the original 5532.You are paying for this very special board and it is a necessity if you want to use the AD 825's.

ben62670

Those boards are very reasonably priced.
Ben

Systems

ben62670 wrote: »

Those boards are very reasonably priced.
Ben

$38 is not bad considering its specialized nature and it comes with 2 premium op amps already installed.

Edit: however after re reading the first post an extra $135 to install it is insane.If you can solder and desolder it should be a simple mod to do.

fbm211

Well then its time to order that desoldering iron from PE.Might as well find out what caps I need to get for the power supply and change them too.I think Ill go with black gate.And rubycon ZG/ZLG if some of the blackgates are no longer available.

Systems

Get yourself a good soldering staion like the Weller WTCPT and a solder pump (sucker) and you will be well equipt for the job.

I use the Soldapullt model DS017 pump(see link)
http://www.hmcelectronics.com/cgi-bin/scripts/product/2920-0019/

Another good and economical choice for upgrading the power supply decoupling caps is the Panasonic FC series.

fbm211

What about this tool for desoldering.And do I need wicks,heat sinks scrapers etc.Im new to this electronic modding thing. http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=370-325

Systems

fbm211 wrote: »

What about this tool for desoldering.http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=370-325

Yes that would be perfect, and yes you should also have a roll of wick and a solder pick.

Face

For larger joints, I use a desoldering bulb, smaller joints, a desoldering braid. I usually keep a clipped off lead from a mills resistor around while using the bulb, they clog every so often, and the lead is the perfect size to clear the hole.

heiney9

I'll be watching this thread so be sure to update. I have a 600 as well and I already really like the way it sounds, so if this upgrade can be done fairly easily and it's worthwhile I may try it.

H9

sucks2beme

Check the power supply diodes, and if they aren't FRED(fast recovery diodes)
replace them with FREDs with the same ratings.

fbm211

Waiting on parts.(opamp)And a digital camera to post several pics of the mod in stages.Thanks guys.Im going to call adcom and see if I can get a schematic.That would help a-lot for ordering caps and diodes.