I bet they do... u should also have 0.1 uf soldered right onto the last caps ...if u don't have them already
Yeah, I had them close to the LM3886. Everything was hardwired by the way, no PCB. The amp had just one channel by the way, a single LM3886 and a very big PSU.
Had to add another post.....
I have been listening to the amp all afternoon and was so amazed at the quality that can be obtained from such a minimal amount of components. I was convinced that it sounded better than my Denon amp, so I called a friend to come and audition it. He brought over some well recorded orchestral music and after half an hour of listening, is convinced that it sounds as good as his £3000 Arcam setup. He said he was stunned at the ease of listening of the music produced.
Can anyone else comment on comparisons to other high end audio equipment? I've only used cheap components in the amp and can't wait to build some mono blocks with higher quality components.
I have been listening to the amp all afternoon and was so amazed at the quality that can be obtained from such a minimal amount of components. I was convinced that it sounded better than my Denon amp, so I called a friend to come and audition it. He brought over some well recorded orchestral music and after half an hour of listening, is convinced that it sounds as good as his £3000 Arcam setup. He said he was stunned at the ease of listening of the music produced.
Can anyone else comment on comparisons to other high end audio equipment? I've only used cheap components in the amp and can't wait to build some mono blocks with higher quality components.
It just flat out DOES sound better than a lot of high dollar stuff. A badass power supply can make it even better. Something like the F5 supply is really nice. I finally like my new build. I used the Gold Tone caps in power supply from Nichicon. It took a loooong time for them to loosen up but finally things broke through and the veil it had is gone. I like Panasonic FC on the 100uf if you used 100uf on Pins 1,3 and 8. They are super detailed. Some say to harsh. I like it that way I guess. However while this smokes a lot of silicon amps in the stores most tube amps I have listened to in the past few years have beat it handily. Not cheap tubes mind you so for sure the chip amp wins out over the tubes in sound quality per dollar.
Nope, dont have specific amp references.
Uriah
Nope, dont have specific amp references.
Uriah
Thanks for your reply udailey. What do you mean by an 'F5 supply'?
At the moment, my power comes form a toroidal transformer feeding 2 cheap bridge rectifiers. The output of these goes straight to my amp PCBs. I have no smoothing caps at all on the power supply, and all of the components used on the amp boards are standard cheap ones. The idea of this first build was to see the music quality achievable with basic parts.
My plan is to replace my Denon 7.1 surround amp with a cheap pre-amp, capable of AC3 decoding, and drive my speakers with mono blocks built from LM3875s. Has anyone had any experience with 'HLLY High End DTS AC3 5.1'?
At the moment, my power comes form a toroidal transformer feeding 2 cheap bridge rectifiers. The output of these goes straight to my amp PCBs. I have no smoothing caps at all on the power supply, and all of the components used on the amp boards are standard cheap ones. The idea of this first build was to see the music quality achievable with basic parts.
My plan is to replace my Denon 7.1 surround amp with a cheap pre-amp, capable of AC3 decoding, and drive my speakers with mono blocks built from LM3875s. Has anyone had any experience with 'HLLY High End DTS AC3 5.1'?
Hi Pato666. The milling was done on a cheap pillar drill with an end mill in the chuck.
An example of how I produced the hole for one of the phono sockets:
1. Drill a 6.5mm hole through the aluminium
2. Use a countersink bit to expand the hole to about 21mm
3. Use a 20mm end mill to mill the hole to the desired depth.
The countersinking bit is used to give the end mill a bit of guidance. Without the angled sides that the countersink bit makes, the end mill (when used in a cheap pillar drill) seems to bounce around and doesn't drill very well at all.
An example of how I produced the hole for one of the phono sockets:
1. Drill a 6.5mm hole through the aluminium
2. Use a countersink bit to expand the hole to about 21mm
3. Use a 20mm end mill to mill the hole to the desired depth.
The countersinking bit is used to give the end mill a bit of guidance. Without the angled sides that the countersink bit makes, the end mill (when used in a cheap pillar drill) seems to bounce around and doesn't drill very well at all.
F5 power supply is here http://www.firstwatt.com/downloads/F5-om_sm-080527.pdf
Nelson Pass design. The F5 will spank the chip amp but no doubt the chip amp is a great amp and a lot of fun to build and listen to. Anyway, the power supply really makes the chip amp a bit of a beast. The bass is super solid and just about everything about the music improves. If you consider it I would buy the BrianGT Aleph Mini power supply board for $9. To avoid the looong time I endured to get rid of that veil I would go with Panasonic TSHA caps or go to ApexJr.com and get his Nichicon 10000uf caps which might still have that veil for a while but are only 2.99 each and are actually quite good. Either way 10000uf for each power supply cap. With that board you need 6. It is basically the Nelson Pass F5 power supply. Its a fantastic supply you can use and reuse in a lot of amps.
Uriah
Nelson Pass design. The F5 will spank the chip amp but no doubt the chip amp is a great amp and a lot of fun to build and listen to. Anyway, the power supply really makes the chip amp a bit of a beast. The bass is super solid and just about everything about the music improves. If you consider it I would buy the BrianGT Aleph Mini power supply board for $9. To avoid the looong time I endured to get rid of that veil I would go with Panasonic TSHA caps or go to ApexJr.com and get his Nichicon 10000uf caps which might still have that veil for a while but are only 2.99 each and are actually quite good. Either way 10000uf for each power supply cap. With that board you need 6. It is basically the Nelson Pass F5 power supply. Its a fantastic supply you can use and reuse in a lot of amps.
Uriah
Pato,
I really dont know. I have not studied what is best for ripple current. I can only justify my recommendation on experimentation and having built several chipamps with several different power supplies and having used 3 different brands of caps for power supply including TSHA. They were really fast. You could hear it in the music. You will often see people recommend the Panasonic TSHA as a good power supply cap. I am using it in the MYREFC Ultimate BOM because first it fits the board but second it has been a great performer for a lot of chipamp builders as well as class A amp builders and the price is very affordable. Its not a 30 dollar cap but its one of the best inexpensive caps and it fits nicely in the circuit board I recommended. I think that building up your power supply is going to wow you with that amp. What you have right now is only the beginning of how good it can sound. Looks great to!
I really dont know. I have not studied what is best for ripple current. I can only justify my recommendation on experimentation and having built several chipamps with several different power supplies and having used 3 different brands of caps for power supply including TSHA. They were really fast. You could hear it in the music. You will often see people recommend the Panasonic TSHA as a good power supply cap. I am using it in the MYREFC Ultimate BOM because first it fits the board but second it has been a great performer for a lot of chipamp builders as well as class A amp builders and the price is very affordable. Its not a 30 dollar cap but its one of the best inexpensive caps and it fits nicely in the circuit board I recommended. I think that building up your power supply is going to wow you with that amp. What you have right now is only the beginning of how good it can sound. Looks great to!
i really like that
Thanks. I was a bit concerned about the "grill", but all high voltage connections are well insulated and when the enclosures are stacked only the amp module is accessible.
- Matt
An 'accepted value' is when you cannot perceive any ripple through your speakers or headphones. With the PSRR specification of the LM series you can afford a lot of ripple. That is why the Gaincard and many of its clones get away with 1000 µF per rail.
The reason for big capacitors is not only the ripple suppression. It is also a matter of bringing down the power supply's inner impedance. The bigger the capacitance, the lower the frequency unto which the impedance remains low. And when the impedance is low the voltage drop across the power supply remains low as well, which in turn leads to a more constant amplifier output voltage inspite of the varying load a speaker poses at different frequencies.
I've seen this schematic on chipamp.com
UDailey, is this a good supply, anywhere near the quality of the F5 PSU?
Also, please can someone explain the 0.1uF cap in series with a 1R across the output.
An externally hosted image should be here but it was not working when we last tested it.
UDailey, is this a good supply, anywhere near the quality of the F5 PSU?
Also, please can someone explain the 0.1uF cap in series with a 1R across the output.
I dont think its real close to the F5 but its a lot less expensive.
Here is a better CarlosFM supply
Point to point wired LM3886 chip amplifier with a hi-cap snubberised PSU.
Then you can read about his improvements to the LM3886 circuit. Okay, improvements in his mind and in many others. He really did a lot with LM3886 before they banned him. Sure he probably still does but anyway he changes it several times so read the first few pages at a minimum. He might go over the supply and explain it later but I am not sure. Nuuk has a good description of the circuit over at decibel dungeon.
http://www.diyaudio.com/forums/chip...nverting-chipamp.html?perpage=50&pagenumber=1
Uriah
Here is a better CarlosFM supply
Point to point wired LM3886 chip amplifier with a hi-cap snubberised PSU.
Then you can read about his improvements to the LM3886 circuit. Okay, improvements in his mind and in many others. He really did a lot with LM3886 before they banned him. Sure he probably still does but anyway he changes it several times so read the first few pages at a minimum. He might go over the supply and explain it later but I am not sure. Nuuk has a good description of the circuit over at decibel dungeon.
http://www.diyaudio.com/forums/chip...nverting-chipamp.html?perpage=50&pagenumber=1
Uriah
Buffered LM3875 mini amplifier
I made this amp for my desk at work. Input runs through monocor LTR-110 transformers to 50K smd attenuator, then a FET buffer board from ebay before the LM3875s. The input transformers are there because the amp will be used to test audio content on different laptops & other sources, and this solves the ground loop & noise issues you often get with laptops etc.
I made this amp for my desk at work. Input runs through monocor LTR-110 transformers to 50K smd attenuator, then a FET buffer board from ebay before the LM3875s. The input transformers are there because the amp will be used to test audio content on different laptops & other sources, and this solves the ground loop & noise issues you often get with laptops etc.
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