Hello All.
New member here - first of all while I do enjoy decent hifi it's always been at the budget end, and my experience in electrical work has been limited to (recently) changing a capacitor each on a Meade telescope handset and a Roland JV 1080 synth expansion card.
I cannot read schematics etc so consider me a complete newbie please.
My home theater receiver is a 20 year old Nad T753. I love the sound of Nad, having used them in the UK before I moved to the States.
My CD player is an Onkyo 7030 C. Budget end but well respected apparently. Had it for around 6 years.
A few weeks ago (on a Facebopok hifi group) I saw Discrete Op Amps mentioned.
Not having heard of them I looked them up and started some research. I wondered if I put a few in my Nad and/or the Onkyo I'd improve the sound.
I stress I'm not unhappy with the sound but with a few cheap tweaks wondered if I could improve it.
That was....until I saw the sticker price of a single Discrete Op Amp.
I'd downloaded the Service Manual for the Nad and it showed 9 IC NJM5532M Op Amps (the DAC is apparently a Cirrus Logic CS4340).
I opened up the Nad yesterday with a view to confirming the above - but no way am I trying to take this apart - I'd never get it back again.
I looked inside the Onkyo and that shows 5 Op Amps - JRC 4580D's (assuming I got that right with my magnifying glass).
The DAC looks to be a Wolfson WM 8718S.
Would I likely get any improvement if I had drop in replacements for the JRC 4580D's. Another IC Op Amp? If so what would be suggested as a replacement?
If I changed out any IC Op Amp's for a Discrete - I'd be tempted if I could change just one. Is that possible? Would it need more than that?
I could instead put the Discrete money towards a Cambridge Audio DacMagic ($200). As said - the Nad DAC is a Cirrus Logic CS4340, with the Onkyo being a Wolfson WM8718S. The DAC used in the Cambridge Audio is apparently a Wolfson WM 8742.
Am I going to get $200 worth of difference here? I currently use the Onkyo DAC - I have switched between the Nad/Onkyo - there seems little difference.
I have looked at a few threads here -I have seen some for and against the Discrete versions and if anywhere - due to cost I'm leaning against. Tempted but probably no more than one.
Finally - I'm also tempted to upgrade the Nad. A Nad T758 or a Marantz 7015 are on a shortlist. I'm leaning towards the Marantz as Nad's quality control seems to have some criticisms (and I have experience with that too).
Neither are out just yet and I'm okay with keeping the 753 a while longer.
Any advice on the above is appreciated, and apologies for the length of this - went on a bit longer than I thought it would. 🙂
New member here - first of all while I do enjoy decent hifi it's always been at the budget end, and my experience in electrical work has been limited to (recently) changing a capacitor each on a Meade telescope handset and a Roland JV 1080 synth expansion card.
I cannot read schematics etc so consider me a complete newbie please.
My home theater receiver is a 20 year old Nad T753. I love the sound of Nad, having used them in the UK before I moved to the States.
My CD player is an Onkyo 7030 C. Budget end but well respected apparently. Had it for around 6 years.
A few weeks ago (on a Facebopok hifi group) I saw Discrete Op Amps mentioned.
Not having heard of them I looked them up and started some research. I wondered if I put a few in my Nad and/or the Onkyo I'd improve the sound.
I stress I'm not unhappy with the sound but with a few cheap tweaks wondered if I could improve it.
That was....until I saw the sticker price of a single Discrete Op Amp.
I'd downloaded the Service Manual for the Nad and it showed 9 IC NJM5532M Op Amps (the DAC is apparently a Cirrus Logic CS4340).
I opened up the Nad yesterday with a view to confirming the above - but no way am I trying to take this apart - I'd never get it back again.
I looked inside the Onkyo and that shows 5 Op Amps - JRC 4580D's (assuming I got that right with my magnifying glass).
The DAC looks to be a Wolfson WM 8718S.
Would I likely get any improvement if I had drop in replacements for the JRC 4580D's. Another IC Op Amp? If so what would be suggested as a replacement?
If I changed out any IC Op Amp's for a Discrete - I'd be tempted if I could change just one. Is that possible? Would it need more than that?
I could instead put the Discrete money towards a Cambridge Audio DacMagic ($200). As said - the Nad DAC is a Cirrus Logic CS4340, with the Onkyo being a Wolfson WM8718S. The DAC used in the Cambridge Audio is apparently a Wolfson WM 8742.
Am I going to get $200 worth of difference here? I currently use the Onkyo DAC - I have switched between the Nad/Onkyo - there seems little difference.
I have looked at a few threads here -I have seen some for and against the Discrete versions and if anywhere - due to cost I'm leaning against. Tempted but probably no more than one.
Finally - I'm also tempted to upgrade the Nad. A Nad T758 or a Marantz 7015 are on a shortlist. I'm leaning towards the Marantz as Nad's quality control seems to have some criticisms (and I have experience with that too).
Neither are out just yet and I'm okay with keeping the 753 a while longer.
Any advice on the above is appreciated, and apologies for the length of this - went on a bit longer than I thought it would. 🙂
Welcome to diyAudio Dave 🙂
Swapping oamps can be fun and can in some cases get you a slightly different 'character' to the sound. There are as many different opinions out there as there are opamps and so the only way you will know is to replace them and see.
I would recommend you fit sockets and then you can swap devices and compare.
I would suggest you try something like the LM4562 which is a very high quality device and replaced the NE5532.
I'm also going to say you try the TL072 which is a FET device. Ignore the naysayers and make up your own mind. Its a terrific device let down mainly by limited current drive ability, a limit which you won't even get close to at the signal levels involved here.
Now try something like a 1458. This is like a dual 741 opamp, in other words as bad as it gets for audio these days. But what do you think? It gives you a reference point of the very worst performing type of device vs devices aimed at high quality audio.
You have to hear differences for yourself and these three will let you do that plus they all cost buttons in the scheme of things.
Also always always buy from reputable authorised distributers. Fake devices are rife and that super expensive chip might be little more than a remarked 'something else' if you are not careful.
Swapping oamps can be fun and can in some cases get you a slightly different 'character' to the sound. There are as many different opinions out there as there are opamps and so the only way you will know is to replace them and see.
I would recommend you fit sockets and then you can swap devices and compare.
I would suggest you try something like the LM4562 which is a very high quality device and replaced the NE5532.
I'm also going to say you try the TL072 which is a FET device. Ignore the naysayers and make up your own mind. Its a terrific device let down mainly by limited current drive ability, a limit which you won't even get close to at the signal levels involved here.
Now try something like a 1458. This is like a dual 741 opamp, in other words as bad as it gets for audio these days. But what do you think? It gives you a reference point of the very worst performing type of device vs devices aimed at high quality audio.
You have to hear differences for yourself and these three will let you do that plus they all cost buttons in the scheme of things.
Also always always buy from reputable authorised distributers. Fake devices are rife and that super expensive chip might be little more than a remarked 'something else' if you are not careful.
Thanks for replying Mooly.
I had bookmarked the LM4562. I think I saw it mentioned in an old post either here or Audiokarma re replacing opamps in the 7030.
I think the 4580D now in the 7030 shows "thru hole" at Mouser. Does this mean desoldering - and then putting in the socket you mention?
Any links to how to desolder these tiny items and the socket required are appreciated. I will research myself though - I'm retired so have "some" time on my hands.
I have some desolderong braid, if that's the right term (from doing the aforementioned capacitors)- but doing so is a bit scary. The 7030 is budget end so any loss is not the end of the world, I might just have to research replacements 🙂
My soldering iron may be too bulky for the task as well - it's a basic Radio Shack.
Thanks again.
I had bookmarked the LM4562. I think I saw it mentioned in an old post either here or Audiokarma re replacing opamps in the 7030.
I think the 4580D now in the 7030 shows "thru hole" at Mouser. Does this mean desoldering - and then putting in the socket you mention?
Any links to how to desolder these tiny items and the socket required are appreciated. I will research myself though - I'm retired so have "some" time on my hands.
I have some desolderong braid, if that's the right term (from doing the aforementioned capacitors)- but doing so is a bit scary. The 7030 is budget end so any loss is not the end of the world, I might just have to research replacements 🙂
My soldering iron may be too bulky for the task as well - it's a basic Radio Shack.
Thanks again.
Through hole parts (DIP8 package, they are the big ones 😀) are easily desoldered from single sided boards using braid. Practice if you can on something of no value like an old remote etc.
Use a hot iron and a big tip that holds the heat. If you apply a little fresh solder to the braid/and/or iron tip and then just firmly press it and the braid against one leg at a time the solder should come off instantly.
All 8 legs of a DIP8 can be unsoldered in around 10 seconds once you have the knack.
If the board is double sided then you are probably best snipping each leg of the IC with close cropping cutters and then removing each bit of lead left in the board using heat from the iron and a gentle pull with pointy pliers. Then clean the hole using heat to melt the solder in there and poking a bit of stainless wire (solder won't adhere to that) through at the same time. Then use braid to remove the excess solder the wire has pushed out.
Then fit your sockets. There will be a little identifying mark for pin 1. Although it doesn't matter electrically for the socket, it most certainly does for the chip and so its good to have sockets fitted with the correct orientation.
And a tip... when you remove an IC from a socket gently lever one end and then the other alternately a mm at a time until it is free. Lever it out in one go and it will suddenly release bending half the legs at 90 degrees leaving the other half painfully embedded in your finger 🙁
Use a hot iron and a big tip that holds the heat. If you apply a little fresh solder to the braid/and/or iron tip and then just firmly press it and the braid against one leg at a time the solder should come off instantly.
All 8 legs of a DIP8 can be unsoldered in around 10 seconds once you have the knack.
If the board is double sided then you are probably best snipping each leg of the IC with close cropping cutters and then removing each bit of lead left in the board using heat from the iron and a gentle pull with pointy pliers. Then clean the hole using heat to melt the solder in there and poking a bit of stainless wire (solder won't adhere to that) through at the same time. Then use braid to remove the excess solder the wire has pushed out.
Then fit your sockets. There will be a little identifying mark for pin 1. Although it doesn't matter electrically for the socket, it most certainly does for the chip and so its good to have sockets fitted with the correct orientation.
And a tip... when you remove an IC from a socket gently lever one end and then the other alternately a mm at a time until it is free. Lever it out in one go and it will suddenly release bending half the legs at 90 degrees leaving the other half painfully embedded in your finger 🙁
