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My_Ref Fremen Edition - Build thread and tutorial
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Old 4th March 2021, 10:38 AM   #4791
turion64 is offline turion64  United States
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My_Ref Fremen Edition - Build thread and tutorial
Puffin: As Joseph K has already stated, Dario’s suggested BOM, even using his suggested "audiophile" components upgrade, will lead to a "balanced & warm" sounding amp. The use of naked Z-foils and Amtran’s AMCHs will bring more delicacy to the upper end but having not heard a Russ White build I can’t comment on the differences between builds.

For informations sake, you could go look at this thread:

“Fremen Edition My_Ref Amplifier – Completed Projects and Photos” to compare various builds and impressions on SQ.

Cheers
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Old 4th March 2021, 10:45 AM   #4792
Puffin is offline Puffin  United Kingdom
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Thanks for the replies guys. I used good quality components to populate the board. I was not aware that the presentation of this version of a GC was designed to be smoother than the 2 caps and half a dozen resistors circuit a la 47 Labs. I may try reducing the PS capacitance. I also understand that C9 is a candidate for experimentation to tailor the sound.
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Old 4th March 2021, 01:18 PM   #4793
lehmanhill is offline lehmanhill  United States
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Smaller PS caps is likely to change the sound, but I would be surprised if it has much effect on HF content. Bigger caps often have more ESR which can effect the ability of the cap's ability to respond to large current demands. But HF content usually doesn't require much in the way of PS current. Still, it is worth a try. The "audiophile" choice of Mundorf caps is there because they have lower ESR and you can hear it in improved bass definition. But I don't hear any difference in the HF content.

While George and Pete are correct in characterizing the smooth, warm sound of the FE amp, I wonder if you are describing something bigger that might be indicating a problem? Although smooth, I have never felt I was missing HF content.

But if you are talking character choices, then yes, components do make a difference, and it seems more than than other amps because of the current pump architecture, at least IMHO. And if you find yourself playing with C9, I suggest that C13 is the most influential on sound character and I think that C13 and C9 interact. I have tried combinations where the HF content became too much and everything became etched and a little harsh.

Jac
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Old 4th March 2021, 01:55 PM   #4794
Joseph K is offline Joseph K  Hungary
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Good points, Jac. As usual.

Also. Poor me. Do not have neither C13, nor C9 to play with.. What an ethereal dullness.
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Old 4th March 2021, 04:28 PM   #4795
Puffin is offline Puffin  United Kingdom
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Quote:
Originally Posted by lehmanhill View Post
Smaller PS caps is likely to change the sound, but I would be surprised if it has much effect on HF content. Bigger caps often have more ESR which can effect the ability of the cap's ability to respond to large current demands. But HF content usually doesn't require much in the way of PS current. Still, it is worth a try. The "audiophile" choice of Mundorf caps is there because they have lower ESR and you can hear it in improved bass definition. But I don't hear any difference in the HF content.

While George and Pete are correct in characterizing the smooth, warm sound of the FE amp, I wonder if you are describing something bigger that might be indicating a problem? Although smooth, I have never felt I was missing HF content.

But if you are talking character choices, then yes, components do make a difference, and it seems more than than other amps because of the current pump architecture, at least IMHO. And if you find yourself playing with C9, I suggest that C13 is the most influential on sound character and I think that C13 and C9 interact. I have tried combinations where the HF content became too much and everything became etched and a little harsh.

Jac
Thanks for your reply Jac. I will see what more exotic caps can do at C9 and C13. Rob.
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Old 4th March 2021, 09:20 PM   #4796
ClaveFremen is offline ClaveFremen  Italy
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Quote:
Originally Posted by Puffin View Post
I am not sure if anyone is able to comment, but having built a MyRef_C (Russ White Red Board 1.2 2006) I am finding the sound really lacking much HF content. I have used all the correct values for the on-board components except for the PS caps. These are suggested to be 10,000uf. I had some nice Panasonic 18,000uf caps left over from another project and so I used these. Could these have too much capacitance?

There is something wrong, the amp has no such thing as lack of hf content...


The PS caps value should not be a problem but could have imparted a different sound signature than the inteded one but unless they're awful I would exclude them as the source fo the problem.


Quote:
Originally Posted by Puffin View Post
By the way Dario has been away from posting on here lately. I hope that he is well.

I'm fine, simply at work night & day, 11PM here and I'm patching several customers Exchange servers for a zero day vunerability...



Quote:
Originally Posted by Puffin View Post
Thanks for the replies guys. I used good quality components to populate the board. I was not aware that the presentation of this version of a GC was designed to be smoother than the 2 caps and half a dozen resistors circuit a la 47 Labs.

No, it's not, more later


Quote:
Originally Posted by Joseph K View Post
What I know is that the BOM of Dario seem to be directed for a 'balanced' sound, rather the warm side, as in contrast with sheer resolution.
Quote:
Originally Posted by Joseph K View Post
In any case, yes, I would could confirm that a well executed Myref amp is leaning to more the natural balance then the 'classic SS' sound.
There had been a lot of work & attention spent on 'polishing' the rough edges..
Quote:
Originally Posted by turion64 View Post
Puffin: As Joseph K has already stated, Dario’s suggested BOM, even using his suggested "audiophile" components upgrade, will lead to a "balanced & warm" sounding amp. The use of naked Z-foils and Amtran’s AMCHs will bring more delicacy to the upper end
Mmmh... Guys where did you took this from?



'warm' sound or "'polishing' the rough edges" are never been goals for the voicing of the amp...


Up to version 1.2 the component selection was made upon best perceived sound from several components and here the 'polishing' thing may have some merit but mostly was what sounded better to my (and others, as BCMBOB) ears.


From version 1.5 a radical different approach has been taken with the goal of the maximum possible neutrality and maximum detail, the amp has slight hint of a warm signature due to the RN55 resistors that has been selected for other desirable traits like details and noise floor and Wima FKP2 caps.


Must be taken in account that the real deal is the BOM with audiophile parts, which is pretty neutral.



Puffin can you share the exact BOM you used so that I can help you identify the possible culprits?


Anyway if the HF lack is serious I would suspect an error on the LM318 compensation network.


If not C13 and C9 have a big impact on sound.
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Last edited by ClaveFremen; 4th March 2021 at 09:24 PM.
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Old 5th March 2021, 12:01 AM   #4797
turion64 is offline turion64  United States
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Quote:
Originally Posted by ClaveFremen View Post
There is something wrong, the amp has no such thing as lack of hf content...

Mmmh... Guys where did you took this from?
Itís what we hear Dario. This is meant as a compliment. I love the sound of my Evo A build with the audiophile components. The warmth envelopes you while the upper end is beautifully articulated and clean. I would never describe it as "bright" however, not with a LM318 in place. My other build, with ADA4627 in place, shifts the music towards the upper end.

My speakers, my DAC, my listening environment, will give me a different experience.

With respect,

Pete
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Old 5th March 2021, 07:00 AM   #4798
Puffin is offline Puffin  United Kingdom
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Quote:
Originally Posted by ClaveFremen View Post

I'm fine, simply at work night & day, 11PM here and I'm patching several customers Exchange servers for a zero day vunerability..


Puffin can you share the exact BOM you used so that I can help you identify the possible culprits?


Anyway if the HF lack is serious I would suspect an error on the LM318 compensation network.


If not C13 and C9 have a big impact on sound.
Glad to hear that you are well. CV-19 has made the world a very different place.

This is the BOM I used :-

Number Desc 1 Desc 2 Desc 3 Source Part Number per count total
D1-D3 1N4001 1A - 50V Diodes On Semi Digikey 1N4001RLOSCT-ND 0.224 3 0.672

Q2-Q3 BC546 NPN Bipolar Transistor On Semi Digikey BC546BOS-ND 0.164 2 0.328

Q1 BC639 NPN Bipolar Transistor Fairchild Mouser 512-BC639 0.18 1 0.18

ZD1-ZD4 BZX85-XX 12V 1.3W Zener Diode Fairchild Mouser 512-BZX85C12 0.08 4 0.32

C7, C23 100nF MKT (box) 50V Capacitor Panasonic Digikey P4593-ND 0.108 2 0.216
C10, C25 100pF MKT (box) 50V Capacitor Panasonic Digikey P4570-ND 0.072 2 0.144
C12, C27 220pF MKT (box) 50V Capacitor Panasonic Digikey P4574-ND 0.072 2 0.144

C4, C5, C19, C22 100nF MKT (box) 100V Capacitor Panasonic Digikey P4656-ND 0.159 4 0.636

C13, C29 1uF MKP (box) 50V Capacitor Panasonic Digikey E1105-ND 0.741 2 1.482

C9, C14, C22 220uF Radial 50V EL Capacitor Sanyo AX Bdent 63MV220AX 0.4 3 1.2

C1-2, C17-18 220uF Radial 50V lowESR EL Capacitor Sanyo FZ Bdent 50MV220FZ 1.04 4 4.16

C3, C8, C20, C28 10000uF 50V EL Caps Sanyo DAC Bdent 50PL10000DAC 4.29 4 17.16

C15 22uF Radial 25V EL Capacitor Sanyo SAX Bdent 25MV22SAX 0.18 1 0.18

C6, C11, C16, C21, C26 100uF Radial 25V EL Capacitor Sanyo AX Bdent 25MV100AX 0.18 5 0.9

U1-2 LM319N DIL Op Amp National Semi Digikey LM318N-ND 1.017 2 2.034

IC1-2 LM3886 Amp National Semi Digikey LM3886TF-ND 4.16 2 8.32

D1, D5 8A 400V Bridge Rect. Diodes GBT804 Mouser 621-GBJ804 1.52 2 3.04

R5, R8, R28, R31 22K0 .25W .1% IRC .1% RC55 Mouser 66-RC55-D-22.1K 0.96 4 3.84
R6, R9, R29, R32 47K0 .25W .1% IRC .1% RC55 Mouser 66-RC55-D-47.5K 0.96 4 3.84

R2, R25 33K .25W 1% KOA Spear Mouser 660-MF1/4CL3322F 0.12 2 0.24
R7, R30 12K0 .25W 1% KOA Spear Mouser 660-MF1/4CL1202F 0.12 2 0.24
R10, R33 390 .25W 1% KOA Spear Mouser 660-MF1/4CL3920F 0.12 2 0.24
R11, R35 1 .25W 1% KOA Spear Mouser 660-MF1/4CL1R00F 0.17 2 0.34
R12, R34 3K32 .25W 1% KOA Spear Mouser 660-MF1/4CL3321F 0.12 2 0.24
R13, R36 100K .25W 1% KOA Spear Mouser 660-MF1/4CL1003F 0.12 2 0.24
R15-18 75K .25W 1% KOA Spear Mouser 660-MF1/4CL7502F 0.12 4 0.48
R19 10K .25W 1% KOA Spear Mouser 660-MF1/4CL1002F 0.12 1 0.12
R20 47K .25W 1% KOA Spear Mouser 660-MF1/4CL4702F 0.12 1 0.12
R21 220K .25W 1% KOA Spear Mouser 660-MF1/4CL2213F 0.12 1 0.12
R22 8K2 .25W 1% KOA Spear Mouser 660-MF1/4CL8251F 0.12 1 0.12

R23 6K8 .5W 5% KOA Spear Mouser 660-MF1/2CL6811F 0.14 1 0.14

R1, R4, R24, R27 1K 1W 5% Vishay-Dale PRO1 Mouser 594-5073NW1K000J 0.16 4 0.64
R14 470 1W 5% Vishay-Dale PRO1 Mouser 594-5073NW470R0J 0.16 1 0.16

R3, R26 0.47 5W WW Huntington Elec Digikey ALSR5F.50-ND 1.35 2 2.7

RELAY1 24VDC 2sc 8A-250V 24v 8A Omeron Mouser 653-G2RL-24B-DC24 4.1 1 4.1

PL1-8 Faston Connectors (PCB Mount) Digikey A24742-ND 0.055 8 0.44

However, not all the components were of the same manufacture as the BOM, but the values were the same.
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Old 6th March 2021, 01:28 AM   #4799
madisonears is offline madisonears  United States
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Replace your C9 with a Nichicon KZ or FG. Replace your C13 with Amtrans AMCG or Audyn KpSn. These are inexpensive, high quality parts available from HiFi Collective. If you can afford just a bit more, the Auricap XO 200 volt is better yet.

Your amps will be transformed.

Peace,
Tom E
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Old 6th March 2021, 06:10 AM   #4800
Puffin is offline Puffin  United Kingdom
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Quote:
Originally Posted by madisonears View Post
Replace your C9 with a Nichicon KZ or FG. Replace your C13 with Amtrans AMCG or Audyn KpSn. These are inexpensive, high quality parts available from HiFi Collective. If you can afford just a bit more, the Auricap XO 200 volt is better yet.

Your amps will be transformed.

Peace,
Tom E
Ok, thanks for that. Rob.
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