Hi Ajay,
Seriously consider this point. There are always group buys for projects. I have bought some myself. It seems as if you might be able to help our members out possibly. Depending on shipping costs, you may also be able to cover North America as well.
Please contact me personally using my email button. I have some questions for you regarding rough pricing and if you are a professional, or a hobbyist. No worries, I am just looking for a feel for things, very casual.
-Chris
Seriously consider this point. There are always group buys for projects. I have bought some myself. It seems as if you might be able to help our members out possibly. Depending on shipping costs, you may also be able to cover North America as well.
Please contact me personally using my email button. I have some questions for you regarding rough pricing and if you are a professional, or a hobbyist. No worries, I am just looking for a feel for things, very casual.
-Chris
I found the buzzing, it was an incorectly orientated cap on the input selector -15v rail. 
So I couldn't wait to get modding and I installed everything I have waiting to go in! Mad I know but I figured I could evaluate the sound changes and backtrack or make changes later. On initial start up I had no sound on the left channel which I found out was due to a broken solder pad. I was forced to install my new binding posts so I decided to go ahead with the Kimber hardwired to the power stage too. I know this breaks the golden rule of 'one mod at a time', I apologies to those that advised me to do so. I guess I got carried away.
On the first listen I chose Iron Maidens 'Minutes to midnight' as the test track as I'd been listening to it quite a bit leading up to today's mods. The biggest difference is the treble extension which is amazing compared to before. The detail and air is quite striking, giving lots of attack to electric guitar. However it sounds a tad too bright at the moment so I'll see if things settle down after a couple of days. If not I'll try a change of opamp to the the warmer sounding OPA2107.
Pics and details of mods to follow.
So I couldn't wait to get modding and I installed everything I have waiting to go in! Mad I know but I figured I could evaluate the sound changes and backtrack or make changes later. On initial start up I had no sound on the left channel which I found out was due to a broken solder pad. I was forced to install my new binding posts so I decided to go ahead with the Kimber hardwired to the power stage too. I know this breaks the golden rule of 'one mod at a time', I apologies to those that advised me to do so. I guess I got carried away.
On the first listen I chose Iron Maidens 'Minutes to midnight' as the test track as I'd been listening to it quite a bit leading up to today's mods. The biggest difference is the treble extension which is amazing compared to before. The detail and air is quite striking, giving lots of attack to electric guitar. However it sounds a tad too bright at the moment so I'll see if things settle down after a couple of days. If not I'll try a change of opamp to the the warmer sounding OPA2107.
Pics and details of mods to follow.
Preamp PSU and Right poweramp stage
Left channel poweramp. I decided against soldering the Caddock directly on the pins due to the extra heatsink clamp. I also have Caddocks for the poweramp input but I decided not to fit them yet as there are other caps in the signal path to change also. I figure its not worth it unless I do all of them at the same time.
Left channel poweramp. I decided against soldering the Caddock directly on the pins due to the extra heatsink clamp. I also have Caddocks for the poweramp input but I decided not to fit them yet as there are other caps in the signal path to change also. I figure its not worth it unless I do all of them at the same time.
optimise the decoupling on the existing opamp first before you forget how bright it sounds.mikesnowdon said:
Then, when you change opamps again optimise the decoupling before reaching conclusions. Each opamp is likely to behave differently in the same circuit.
Swapping is not good enough, optimise then assess.
Oh! To do this right you need a reference so that your ears can remember what it is like before the changes.
It's not burning in, it's the brain/ear system compensating for what it thinks you want to hear in the long term.
Doh! I didnt know that! 
Thanks.
I wanted to put the resistor inside the coil but the new Kiwames are too big. I thought about piggybacking the resis above the coil and using the vacant hole to fit a screw terminal.
By the way, do you think this could be another reason why the sound is a tad bright?
Rgd,
Mike.
Thanks.I wanted to put the resistor inside the coil but the new Kiwames are too big. I thought about piggybacking the resis above the coil and using the vacant hole to fit a screw terminal.
By the way, do you think this could be another reason why the sound is a tad bright?
Rgd,
Mike.
Thanks man.
I just need to do some refining now. Maybe someone can suggest where to get suitable blanking plugs for he rear panel?
Here's a pic for you to show how to fit the MUR860 diodes:
I tried the op-amp bypass and it sounded a bit thin and lifeless to me. Also I might change the DC blocking caps as I'm not sure if I like the Nichicon MUSE yet. I forgot to mention above; I fitted 100uF Rubycon ZL in the feedback position, which is another cap I might play with later. Apparently this cap has a big effect on the sound of the amp. I also want to try mounting the BG N's directly on the LM3886 pins. Theres also the snubber to experiment with. Did you notice the Silver Mica on the 3886? I also replaced the ceramics on the opamp for silver micas, same value.
The most important thing at the moment is changing the connection of the Kimber to the poweramp stage. I haven't figured this out yet so I need to have a look at the service manual and find a good solution.
I just need to do some refining now. Maybe someone can suggest where to get suitable blanking plugs for he rear panel?
Here's a pic for you to show how to fit the MUR860 diodes:
I tried the op-amp bypass and it sounded a bit thin and lifeless to me. Also I might change the DC blocking caps as I'm not sure if I like the Nichicon MUSE yet. I forgot to mention above; I fitted 100uF Rubycon ZL in the feedback position, which is another cap I might play with later. Apparently this cap has a big effect on the sound of the amp. I also want to try mounting the BG N's directly on the LM3886 pins. Theres also the snubber to experiment with. Did you notice the Silver Mica on the 3886?
I also replaced the ceramics on the opamp for silver micas, same value.The most important thing at the moment is changing the connection of the Kimber to the poweramp stage. I haven't figured this out yet so I need to have a look at the service manual and find a good solution.
Getting back to the tone bypass mod for a minute:
If I do this It will also remove a cap and resistor from the signal path (located in the the tone circuit). The cap Im not worried about as its not needed, but what about the resistor? Its 150k and links between signal and GND (C52,54). I think its part of an attenuation circuit in combination with R82,81 (470R). Am I ok to do the mod and lose these resistors?
If I do this It will also remove a cap and resistor from the signal path (located in the the tone circuit). The cap Im not worried about as its not needed, but what about the resistor? Its 150k and links between signal and GND (C52,54). I think its part of an attenuation circuit in combination with R82,81 (470R). Am I ok to do the mod and lose these resistors?
Hi Mike.
Yes, I know about BrownDogs adapters...
But 7$ for a small adapter (or 9$ for two) it is too high for 5$ opamp I'd better make it by myself or just offer DIP OPA2228 (it's about 8$).
P.s. About my plans. I have bad soldernig-skill (and bad soldering iron too). I understood this just yesterdey, when I finished recapping and changing opamp on my Audigy2. So I'll keep training before I start tweaking 340... Today bought solder--sucker and PCB-holder:
Yes, I know about BrownDogs adapters...
But 7$ for a small adapter (or 9$ for two) it is too high for 5$ opamp
I'd better make it by myself or just offer DIP OPA2228 (it's about 8$).P.s. About my plans. I have bad soldernig-skill (and bad soldering iron too). I understood this just yesterdey, when I finished recapping and changing opamp on my Audigy2. So I'll keep training before I start tweaking 340... Today bought solder--sucker and PCB-holder:
Hi Stream,
You should have got the largest solder sucker. You will also need desoldering braid (solder wick). Some solder flux would be a good investment as well.
There are some soldering stations made in the Far East that are really good. For $120 CDN (at the most), you can buy a temperature controlled station with digital display that displays the current tip temperature. Much better than Weller or Ungar.
Those "helping hands" (PCB holder) are very useful. Mine doesn't have the magnifying glass, but I've had it for over 30 years now. Good investment.
-Chris
You should have got the largest solder sucker. You will also need desoldering braid (solder wick). Some solder flux would be a good investment as well.
There are some soldering stations made in the Far East that are really good. For $120 CDN (at the most), you can buy a temperature controlled station with digital display that displays the current tip temperature. Much better than Weller or Ungar.
Those "helping hands" (PCB holder) are very useful. Mine doesn't have the magnifying glass, but I've had it for over 30 years now. Good investment.
-Chris
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