cool, some hunting around on ebay (using the title of that ali listing) and I came up with these - both seem to be cheaper than the Ali listing. Hope this will help someone else as well.
10X Aluminum Knobs Rotary Switch Potentiometer Volume Control Pointer Hole 6mm D
5 Pcs Adjustable Turn Rotary Knob for 6mm D Shaft Potentiometer | eBay
The 2nd one looks to be the same as the ones you linked on Ali, and the 1st one has an interesting fit inside - I decided to order them both. Less than the cost of a coffee, why not.
10X Aluminum Knobs Rotary Switch Potentiometer Volume Control Pointer Hole 6mm D
5 Pcs Adjustable Turn Rotary Knob for 6mm D Shaft Potentiometer | eBay
The 2nd one looks to be the same as the ones you linked on Ali, and the 1st one has an interesting fit inside - I decided to order them both. Less than the cost of a coffee, why not.
Those should work. The ones I linked are extra-fine machined finish without any scratches or blemishes. High quality look. I have bought sinilar but coarse looking - but very similar.
Built for sound, not looks
Please forgive me for not stuffing my amp into a tin. Got the PCB and perfectly matched FETs as a gift from X - thank you once again X! Just made a simple perspex enclosure to be used as a desktop amp.
For the rail caps I used Panasonic 2200uF. Panasonic FM 470uF for output caps. All the bypass film caps are low cost unknown brands - could not get those red ones locally, and waiting for the results of Stellar's cap rolling adventure.
Incredible that such a tiny (compared to my tube) amp sounds so huge! Amazing sound. I cannot believe I have a Class A HA amp that cost me only about $30.
Please forgive me for not stuffing my amp into a tin. Got the PCB and perfectly matched FETs as a gift from X - thank you once again X! Just made a simple perspex enclosure to be used as a desktop amp.
For the rail caps I used Panasonic 2200uF. Panasonic FM 470uF for output caps. All the bypass film caps are low cost unknown brands - could not get those red ones locally, and waiting for the results of Stellar's cap rolling adventure.
Incredible that such a tiny (compared to my tube) amp sounds so huge! Amazing sound. I cannot believe I have a Class A HA amp that cost me only about $30.
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Hey YOB,
Nice build! Seems like you managed to maximize capacitance with your arrangement, with quality choices to boot. Looks like maybe Panasonic HD, Nichicon KA, and Epcos BOX? I wanted to try the Epcos too but I mis-ordered and got one with 10mm lead spacing... What are the tiny electrolytics you used on the input?
Nice build! Seems like you managed to maximize capacitance with your arrangement, with quality choices to boot. Looks like maybe Panasonic HD, Nichicon KA, and Epcos BOX? I wanted to try the Epcos too but I mis-ordered and got one with 10mm lead spacing... What are the tiny electrolytics you used on the input?
Well, the epcos 2.2uF are quite fat, so I'm hoping it'll still fit into the tin - tins/mints just arrived today, so may have a go at getting it all in in the next few days. fingers crossed! the initial plan was for the tiny electros to be on the backside of the board and the 2.2u on the top side....
Power caps are the 2200u panas recommended earlier, blue caps are KA 2200u 16V, tiny input electros are FGs 4.7u (planning to build my second one with Silmics to see what the fuss is about, investigating 1500-2200uF silmics atm as well) {EDIT: maybe not...2200uf 16v = 4cm! 1000u may be the largest that can fit on the topside! either way seems quite ridiculous, any ideas welcome} Initial plan was to put the 1500uF FR panas on both rail and output.
Epcos was just cuz they were more reasonably priced than the Wimas (searched 2.2uF & 1uF film, sort by cheapest, picked the first real brand which was roughly the same size lol) not sure what exact kind they are, can search it up if you're curious.
Power caps are the 2200u panas recommended earlier, blue caps are KA 2200u 16V, tiny input electros are FGs 4.7u (planning to build my second one with Silmics to see what the fuss is about, investigating 1500-2200uF silmics atm as well) {EDIT: maybe not...2200uf 16v = 4cm! 1000u may be the largest that can fit on the topside! either way seems quite ridiculous, any ideas welcome} Initial plan was to put the 1500uF FR panas on both rail and output.
Epcos was just cuz they were more reasonably priced than the Wimas (searched 2.2uF & 1uF film, sort by cheapest, picked the first real brand which was roughly the same size lol) not sure what exact kind they are, can search it up if you're curious.
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After a few hours playing with caps, it now seems to me that "all the fuss" over the Silmics is...absolutely warranted! I tried paralleling a 1/10 value electrolytic with the main output electrolytic. So I have Nichicon KA 470uF 25V with Silmic 47uF 35V. I am trying to keep the voltage ratings as high as I can fit for lowest distortion (per Cyril Bateman). Anyway, I am surprised to say that this arrangement has yielded a far more dramatic improvement than any of the small film bypasses I have tried.
I was skeptical that the "smoothness" that everyone talks about with Silmics would mean soft treble without detail. Nope. It simply took away the "glare" and replaced it with MORE detail that is more accurate and less fatiguing. The effect is subtle but real. My amp sounds more 3-D, transparent and lifelike (and I thought it was good before!) Now I get what people mean when they describe sound as ""holographic." Even the bass has better control and detail.
I still think the Nichicon AK is a winner in terms of compactness and clarity. The Silmic is the same size for only 1/10 the capacitance! But the Silmic bypass is a definite upgrade, and this combo gets me where I need to be for low bass extension with great sound!
I was skeptical that the "smoothness" that everyone talks about with Silmics would mean soft treble without detail. Nope. It simply took away the "glare" and replaced it with MORE detail that is more accurate and less fatiguing. The effect is subtle but real. My amp sounds more 3-D, transparent and lifelike (and I thought it was good before!) Now I get what people mean when they describe sound as ""holographic." Even the bass has better control and detail.
I still think the Nichicon AK is a winner in terms of compactness and clarity. The Silmic is the same size for only 1/10 the capacitance! But the Silmic bypass is a definite upgrade, and this combo gets me where I need to be for low bass extension with great sound!
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Exactly. In this setup the second electro is the bypass. I didn't expect that it would improve things more than a film, but the Silmic has the big advantage of much wider frequency coverage due to its greater capacitance. Also, with 6.5V DC bias in this amp, I'm running the Silmic at only 20% of its 35V rating (the low distortion "sweet spot" according to Mr. Bateman), plus the Silmics are already the most linear polar electro he ever measured. With these things considered, I would bet that the overall linearity of the amp's output may in fact be greater with the Silmic than with the much smaller films I've tried.
There should still be room for a small film on the SMD side, and I originally thought this would be the best option. But so far I am not convinced that I need it. My totally subjective hunch is that the polyesters may be a bit unfocused in the treble. But need to do more listening tests!
There should still be room for a small film on the SMD side, and I originally thought this would be the best option. But so far I am not convinced that I need it. My totally subjective hunch is that the polyesters may be a bit unfocused in the treble. But need to do more listening tests!
Thanks for the tests and listening impressions! Do you have a part number for the Silmic that you used? Looks like it is worth a try.
The Silmic II I'm using is RFS-35V470MH3#5
Their datasheet has poor English translation, but I find it to be quite on point with the description of the sound.
Due to the silk fiber's pliability, the capacitor makes a dream of the high quality sound. For examples ; ● To relieve the music's vibration energy. ● To decrease the peak feeling sound at high compass and rough quality sound at middle compass. ● To increase massive sound at low compass.
I didn't quite understand the bit about relieving the vibration until I heard it. It's almost like the cap dampens any harsh unnatural ringing in the mids and treble, improving transparency. Again, subtle but real.
Also, a heads up for those interested in the KZ Muse series...they look like very nicely made caps but I haven't gotten to hear them...the leads are actually made with a heavier gauge wire than any other caps I have. They won't fit into the holes in this PCB! The bi-polar ES Muse series has normal leads that fit, but so far I don't like their sound as much as the Silmic.
Their datasheet has poor English translation, but I find it to be quite on point with the description of the sound.
Due to the silk fiber's pliability, the capacitor makes a dream of the high quality sound. For examples ; ● To relieve the music's vibration energy. ● To decrease the peak feeling sound at high compass and rough quality sound at middle compass. ● To increase massive sound at low compass.
I didn't quite understand the bit about relieving the vibration until I heard it. It's almost like the cap dampens any harsh unnatural ringing in the mids and treble, improving transparency. Again, subtle but real.
Also, a heads up for those interested in the KZ Muse series...they look like very nicely made caps but I haven't gotten to hear them...the leads are actually made with a heavier gauge wire than any other caps I have. They won't fit into the holes in this PCB! The bi-polar ES Muse series has normal leads that fit, but so far I don't like their sound as much as the Silmic.
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I have been listening to my Fiio A5 for about a week now due to having either given or sold all my amps away that were in-hand. Then, having a read about all this cap rolling by StellarElephant today got me interested again in hearing my Pocket Class A again.
So I just built my "Daily Listener" amp using a set of rather hot running FETs with 62mA bias. I installed 470uF 16v Nichicon AK's and 100uF 16v Elna Silmic II's and RVF 47uF 25v SMT caps on the SMT side. No film bypass caps on output! Relying on the Silmics to carry me through the mids an treble as StellarElephant suggests.
On input, I am using the usual 2.2uF Wima films but now with some no name brand 10uF 100v electrolytic soldered onto the SMT side. They just barely fit under the lid. I am using rather beefy 2200uF 25v no name power rail caps.
The finishing touch is a 5mm WHITE LED for the power-on indicator. I had to sand down the LED to get it to fit in a 3mm LED space in between the pot body and 3.5mm jack housing. Finally, I happened to find in my fly fishing tackle bag (took my son fishing yesterday) an old Altoids tin that I used to keep flies in. It is painted white on the bottom half and says "Made in Britain". I guess Altoids used to be made in Britain?!
Anyhow, the case looks totally retro and the white LED is a nice touch. The sound is wonderful. I immediately hear the nice sound I was missing with the A5. It is immediately apparent - and I kick myself for not building another daily listener sooner after all my amps were gone.
So I just built my "Daily Listener" amp using a set of rather hot running FETs with 62mA bias. I installed 470uF 16v Nichicon AK's and 100uF 16v Elna Silmic II's and RVF 47uF 25v SMT caps on the SMT side. No film bypass caps on output! Relying on the Silmics to carry me through the mids an treble as StellarElephant suggests.
On input, I am using the usual 2.2uF Wima films but now with some no name brand 10uF 100v electrolytic soldered onto the SMT side. They just barely fit under the lid. I am using rather beefy 2200uF 25v no name power rail caps.
The finishing touch is a 5mm WHITE LED for the power-on indicator. I had to sand down the LED to get it to fit in a 3mm LED space in between the pot body and 3.5mm jack housing. Finally, I happened to find in my fly fishing tackle bag (took my son fishing yesterday) an old Altoids tin that I used to keep flies in. It is painted white on the bottom half and says "Made in Britain". I guess Altoids used to be made in Britain?!
Anyhow, the case looks totally retro and the white LED is a nice touch. The sound is wonderful. I immediately hear the nice sound I was missing with the A5. It is immediately apparent - and I kick myself for not building another daily listener sooner after all my amps were gone.
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hey the white altoids tin looks pretty cool, should hang onto this one
Stellar:
I'm curious about the silmic too, but no way would I be able to fit a 2200 KA + 220 Silmic. may give it a go with a 1000 + 100. I've noticed that the amp had the greatest effect on my A83s so far, which is why I'd still be trying to cater for them at 11 ohms..
From the datasheet: "Miniature High Grade Capacitors for Audio" ... miniature....lol. words escape me. something got lost in translation I think...haha
Since you did away with the small film bypass altogether, how would whacking in a Silmic of desired capacitance and calling it a day work? (i.e no bypass at all) Based on the logic that the silmic can handle mids and highs well, the large(r) capacitance should also allow it to handle lows fine?
Stellar:
I'm curious about the silmic too, but no way would I be able to fit a 2200 KA + 220 Silmic. may give it a go with a 1000 + 100. I've noticed that the amp had the greatest effect on my A83s so far, which is why I'd still be trying to cater for them at 11 ohms..
From the datasheet: "Miniature High Grade Capacitors for Audio" ... miniature....lol. words escape me. something got lost in translation I think...haha
Since you did away with the small film bypass altogether, how would whacking in a Silmic of desired capacitance and calling it a day work? (i.e no bypass at all) Based on the logic that the silmic can handle mids and highs well, the large(r) capacitance should also allow it to handle lows fine?
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