Soldato
for a headphone amplifier there will be a starving student millet PCB complete kit w/chassis available on Friday. They are going to disappear FAST though, especially the tubes.
*** The DIY Audio Thread ***
- Thread starter -Ad-
- Start date
Soldato
I figured this would be the best thread to ask, I'm after a few LM4562 op-amps, I'm going to try upgrading the Chinese DAC and another pre-amp of mine.
I was wondering where people sources theirs from? They seem to be cheaper on e-bay than farnell, but is it possible that they could be fakes?
I've heard of fake caps before now but I wouldn't be surprised if op-amps are also being faked?
I was wondering where people sources theirs from? They seem to be cheaper on e-bay than farnell, but is it possible that they could be fakes?
I've heard of fake caps before now but I wouldn't be surprised if op-amps are also being faked?
Soldato
rswww has them for 5.20 each. I bought mine from there when I was upgrading my old XFI.
http://uk.rs-online.com/web/search/...searchProducts&searchTerm=LME49860NA+&x=0&y=0
http://uk.rs-online.com/web/search/...searchProducts&searchTerm=LME49860NA+&x=0&y=0
Soldato
Cheers, I'll go for an UK source, I think they were around £4 each from farnell, but that's excluding CAT and delivery....
Gurusan, did you notice much of a difference in the XFI after swapping out the op-amps?
Gurusan, did you notice much of a difference in the XFI after swapping out the op-amps?
Soldato
Yeah absolutely. I did it in conjunction with a Sanyo WG 1500uF power filter cap....but I'm pretty sure it's the opamp that made the difference.
This was a long time ago on my old sennheiser hd205 cans which are pretty entry level though...if you have something better you'd probably hear even more of a difference.
This was a long time ago on my old sennheiser hd205 cans which are pretty entry level though...if you have something better you'd probably hear even more of a difference.
A site I recently found selling them:
http://www.audioupgrades.co.uk/na_ma_ha_opamps.shtml
I haven't used them myself yet, may do at some point though (also for LM4562!)
http://www.audioupgrades.co.uk/na_ma_ha_opamps.shtml
I haven't used them myself yet, may do at some point though (also for LM4562!)
Ahhh, sorry mate - having previously read your post and thinking you'd totally missed my point, and re-asking about amplifiers... I've just suddenly realised you were asking whether I wanted my valve amp for headphones or speakers!
D'oh!
Speakers is the answer!
I have gone the opposite way, i am going to transformer couple the dac with some sowter 600 ohm tranformers that i got silly cheap on ebay...
IF you are any good with metal work then the baby huey amplifier on diyaduio sounds super! not a kit though.
Have a look at the world auido designs kel84 if you want a kit.
I've come across that, and all but fallen in love with it! With a 25th birthday coming up next month, It'd be perfect.
But for the fact that it's info pages on the World Designs page are gone, and it's missing from their online catalogue... It would appear it's been discontinued on the quiet
I've dropped the guy an email to make sure however.
Soldato
Cheers gurusan, good to know swapping op-amps seems to make a noticeable difference... 
Are there any more transformers from the same seller at all as I found good transformers to be pretty pricey.
I got one of these yesterday, it uses a Tripath TA2020, same as the 41Hz Amp6:
Now I know it looks pretty horrible and the JRC 4558 is known as the worst op-amp ever, but believe it or not it sounds half decent with no mods.
Some people over at DIYaudio have swapped out op-amps and upgraded the input caps and found that the sound is comparable to the amp6 but is cheaper and involves less soldering...
As I don't own any op-amps I figure a LM4562 would be quick and easy upgrade as this appears already has a rail splitter...
Ooo, nice, I know some people have upgraded the Berry DCX2496's outputs with transformers and have said it beats the op-amp outputs hands down. I recently got a 2nd DCX, so I'm tempted to start upgrading it... Do you just hook the output of the transformer straight up to you amp or is there any additional filtering needed when using audio transformers?
Are there any more transformers from the same seller at all as I found good transformers to be pretty pricey.
I got one of these yesterday, it uses a Tripath TA2020, same as the 41Hz Amp6:
Now I know it looks pretty horrible and the JRC 4558 is known as the worst op-amp ever, but believe it or not it sounds half decent with no mods.
Some people over at DIYaudio have swapped out op-amps and upgraded the input caps and found that the sound is comparable to the amp6 but is cheaper and involves less soldering...
As I don't own any op-amps I figure a LM4562 would be quick and easy upgrade as this appears already has a rail splitter...
Last edited:
I'd look at bypassing the whole input stage (the tone and volume controls) and perhaps upgrading the output filters of the amp. Then there's things like replacing those ceramics if they are in the signal chain and possibly replacing the electrolytics. Still, with all this it looks like a good deal, basically paying for the chip and a functioning PCB!
Soldato
You're also getting enclosure, heatsink & crappy connectors. 
It's a pretty horrible looking enclosure but it can easily be reboxed if you want a pretty amp. 
I've already unsoldered the RCA connectors and put some neutrik ones in, and am looking at how to replace the speaker connectors also.
I'm planning on trying it out in the car and maybe on a 12v portable DIY boombox type thing, so I'm tempted to leave in the tone and volume controls. Someone has already successfully bypassed the tone and volume controls tho, it's only 2 connections, so if you fitted a dual gang switch, you could make the tone controls switchable which is what I'm going to attempt to do .
It was a bargain tho, I paid £18 including delivery, which is just a little more than a bare TA2020 chip costs from 41Hz inc delivery (around 18 euro). There's still a load on e-bay if you want something cheap and cheerful to tinker with. It's pretty crazy you can get an amp for only a little more than the cost of a DVD, I'm tempted to pick up a 2nd just so I can compared an unmodded to modded amp.
Someone over at DIYaudio has also swapped out the output inductors for ones with thicker wire, this gives better bass when the tone controls are disabled, I haven't wound my own toroids yet but I'm tempted to but the bits and give it a go and see how much difference it makes. I think this and the op-amp swap should give quite an improvement.
It's a pretty horrible looking enclosure but it can easily be reboxed if you want a pretty amp. I've already unsoldered the RCA connectors and put some neutrik ones in, and am looking at how to replace the speaker connectors also.I'm planning on trying it out in the car and maybe on a 12v portable DIY boombox type thing, so I'm tempted to leave in the tone and volume controls. Someone has already successfully bypassed the tone and volume controls tho, it's only 2 connections, so if you fitted a dual gang switch, you could make the tone controls switchable which is what I'm going to attempt to do .
It was a bargain tho, I paid £18 including delivery, which is just a little more than a bare TA2020 chip costs from 41Hz inc delivery (around 18 euro). There's still a load on e-bay if you want something cheap and cheerful to tinker with.
It's pretty crazy you can get an amp for only a little more than the cost of a DVD, I'm tempted to pick up a 2nd just so I can compared an unmodded to modded amp. Someone over at DIYaudio has also swapped out the output inductors for ones with thicker wire, this gives better bass when the tone controls are disabled, I haven't wound my own toroids yet but I'm tempted to but the bits and give it a go and see how much difference it makes. I think this and the op-amp swap should give quite an improvement.
Cheers gurusan, good to know swapping op-amps seems to make a noticeable difference...
Ooo, nice, I know some people have upgraded the Berry DCX2496's outputs with transformers and have said it beats the op-amp outputs hands down. I recently got a 2nd DCX, so I'm tempted to start upgrading it... Do you just hook the output of the transformer straight up to you amp or is there any additional filtering needed when using audio transformers?
Are there any more transformers from the same seller at all as I found good transformers to be pretty pricey.
As I don't own any op-amps I figure a LM4562 would be quick and easy upgrade as this appears already has a rail splitter...
you hookup the tranformers to the differential outputs straight of the dac chip, bypassing all the crap downstream.
A low pass filter is required to filter anything over about 30khz (basically a resistor and then a cap across the primaries).
then straight to the outputs
I've come across that, and all but fallen in love with it! With a 25th birthday coming up next month, It'd be perfect.
But for the fact that it's info pages on the World Designs page are gone, and it's missing from their online catalogue... It would appear it's been discontinued on the quiet
how strange, maybe they are just out os stock.
Soldato
Cheers, sounds simple enough, I think I'll keep an eye out for some transformers.
Soldato
just built my mini3....very pleased with how it sounds....I've got to say that I prefer it to my Starving Student which has surprised me a bit. Was not expecting it to have more bass....
I also didn't realize how small this thing actually is....the pics online all make it look bigger than it is for some reason.
I also didn't realize how small this thing actually is....the pics online all make it look bigger than it is for some reason.
Last edited:
Soldato
test
test678
test678
Last edited:
apologies if you follow headfi as you may have seen this. I know a few of you have the original noodle dac so this may be of interest
inspired by some of the various mods being done to a close relative of the noodle dac I decided to go down the tranformer route.
I bought a pair of sowter (uk tranformers) for £7.99 off ebay (they are normally £54 each) and replaced the entire output stage of the dac with two tranformers and a couple of low pass filters (45khz). 1:1 (600 ohms to 600ohms) tranformers are what you want.
How does it sound? natural, that slight glare from the lm4562 is gone, that occasional bass confusion of the opa2107 is gone. It just sounds natural!
inspired by some of the various mods being done to a close relative of the noodle dac I decided to go down the tranformer route.
I bought a pair of sowter (uk tranformers) for £7.99 off ebay (they are normally £54 each) and replaced the entire output stage of the dac with two tranformers and a couple of low pass filters (45khz). 1:1 (600 ohms to 600ohms) tranformers are what you want.
How does it sound? natural, that slight glare from the lm4562 is gone, that occasional bass confusion of the opa2107 is gone. It just sounds natural!