[kirbyt]

Yup I sure did

 

[dacusb]

CGW caps marked, you can leave the existing cap in place and just solder the CGWs to the underside

Hi b0bb,

How many CGW caps do I need to add?
Thank you

 

[b0bb]

Hi b0bb,

How many CGW caps do I need to add?
Thank you

8pcs

 

[dacusb]

8pcs

Hi b0bb.

Thank you very much for your prompt reply.
Can you help further by advising where to get those CGW caps?
Many thanks.

 

[TPSRA]

Hi b0bb
I wonder which one is better, use LKS's Amanero usb receiver USB-100 with linear 5V to connect to DA004,
or do the on board Amanero modding you mentioned above, which will lose the warranty I guess?

 

[Whitigir]

Yes but only if the LKS004 grounding and power routing problems are fixed first.

2 sets of transformers are required one for the digital devices such as the media player, computer, CD player etc and another for the analog side such as headphone amps, power and preamps and the DAC.
Only join the common ground and neutral at the power outlet on the wall (if you have access to an outlet on another circuit, that is better but not always practical and requires knowledge of the house wiring).

Keep in mind RFI filters are needed to isolate incoming interference as well as isolating the digital and analog parts of the audio chain from each other. (This is something LKS forgot when they wired in the enhanced USB board).

Avoid plugging the analog and digital devices on the same isolation transformer or AC re-generator, this is one reason why some people do not see a difference when using just 1 big unit for the whole setup.

If you have the enhanced USB board, the LKS 004 internally joins the digital and analog power lines, this must be corrected (separate transformer and insulated USB metal shield) first before any improvement can be seen.
On the standard USB board, the USB metal shield has to be insulated as it can join the digital and analog grounds thru touching the DAC metal work.

Bobb, what transformer specs should I use to help the Amenero ? I am going to just isolate the USB ground from the chassis ground first. I am interested in separating the amernero like you mentioned. Using my Walkman and it docking station, I am not too worry about the noises passing through from the host to the Amenero, but isolating for galvanic is a good step

Woaa, just a simple modification of isolating the USB away from the main chassis net in a huge improvements. Finer trebles, less noises !! Thanks Bobb

 

[b0bb]

Bobb, what transformer specs should I use to help the Amenero ? I am going to just isolate the USB ground from the chassis ground first. I am interested in separating the amernero like you mentioned. Using my Walkman and it docking station, I am not too worry about the noises passing through from the host to the Amenero, but isolating for galvanic is a good step

Woaa, just a simple modification of isolating the USB away from the main chassis net in a huge improvements. Finer trebles, less noises !! Thanks Bobb

6-8Vac 10-15VA, do not exceed 15VA, use a unit that you can physically fit into the case, any type will do, a RFI filter should be used on the AC input, its job is to prevent noise from the USB interface leaking into the AC mains.
If you can get a transformer with an electrostatic shield, do so.
Do not share this RFI filter with the other transformers on the DAC.

 

[b0bb]

Hi b0bb
I wonder which one is better, use LKS's Amanero usb receiver USB-100 with linear 5V to connect to DA004,
or do the on board Amanero modding you mentioned above, which will lose the warranty I guess?

The USB-100 does not appear to have galvanic isolation on the I2S output, allowing RF noise an unobstructed path into the DAC, the 9038 is very sensitive to RF noise.

USB input on the USB-100 is not insulated from the chassis, similar to the issue seen on the 004.

 

[brickears]

Well ok I went and took the questionable power side of the amenaro out and jumped the board 5v input via an lps-1. Seems to be an improvement for me as I really wasn't enjoying the amenaro input and preferred the singxer via i2s up till now.

Which pins on the Amanero board did you use to power with just the LPS-1 ?

 

[Lennym]

I have had my LKS 004 for about 8 weeks and have enjoyed it very much. I have the upgraded Amanero board and I run ripped DSD files through it perfectly. I have insulated the USB port from the chassis. Thank you b0bb. It sounds great with all sorts of files and with CDs, I can only compare it to my Oppo 105, except that there is no comparison. I've been a mostly analog listener, but now I share my time equally with digital. Never did that before.

I have posted over at the 004 thread. Like everyone else I have been concerned about the heat and its effect on adjacent caps and I have installed these heatsinks, each over two transistors: http://uk.rs-online.com/web/p/heatsinks/1899306/?searchTerm=1899306 They seem to be working well. Following the lead of the poster who suggested these I'll also install some sil-pads.

However on Hiendy, a Chinese forum (I don't read Chinese) also concerned with the heat and the factory's non-response to inquiries on the subject, a poster recently posted the following that I thought might be of interest here:

"Today, into the Zo kind of heatsink, comes with stickers. With a cable fixed, boot a clock with the fingers touch heatsink good heat. But there is hot to bounce (due to the younger thermometer is broken.) Estimated regulator working temperature can be controlled Department of 50 degrees below." Google Transl.

 

[Whitigir]

Any pulsar mod on 004 yet ?

 

[Carlo7]

Shenzhen Audio is also selling it
http://www.shenzhenaudio.com/l-k-s-...nnel-decoder-amanero-usb-dsd-dac-crystek.html

LKS configured the 9038 to re-clock all incoming streams, the custom re-clock logic that you will be paying for on the SU-1 largely goes to waste.
The cost is within 50USD of the Pulsar OCXO, this replaces the XO in the DAC at the the very centre of the 9038's re-clock logic, I think that mod has better value for the money.

LKS paid little attention to the I2S interfaces, most of the logic is powered by the slow and somewhat noisy LM317, the LM317 is a huge step backward from the LT317 used on the 003.
Take a look at how PSAudio implemented I2S and compare to see how I2S is poorly done on the LKS.

I do not see any major changes in the I2S section between the 003 and 004 and expect the same kinds of problems with the SU-1, namely clicks and sometimes loud bangs when switching sample rates or mode changing between PCM and DSD.

Link below describes how the SU-1 does not play nicely with the LKS 003.
https://www.head-fi.org/f/threads/lks-audio-mh-da003.745032/page-25#post-12927931

The very same seller in your link blamed the LKS and walked away leaving the customer high and dry.
Suggest you check to see if the seller eventually made it right for the customer.

LKS utterly messed up the enhanced USB interface implementation on the 004.

• The USB thing is powered by a secondary winding off the digital transformer, creating a direct path for digital noise from the host + the USB board right into to the DAC. Toroids have very wide bandwidth giving the noise a very low impedance path coupled through the secondary windings, this bypassed the interwinding screen on the transformer rendering it useless.
• LKS did not insulate the USB input from the rest of the DAC metal work, this joined the ground on the host and the DAC completely bypassing the galvanic noise isolator.

This amateurish blunder robbed the 004 of a large chunk of its potential.

The fix is simple, power the USB board with its separate transformer with an interwinding screen between the primary and secondary windings and most importantly insulate the USB input from the rest of the metalwork.

The SQ difference after this change is not subtle.
Improvement on a level similar to the step up in SQ between the 003 and the stock 004



That is expected, the unbalanced output is driven by an fully buffered active filter, this allows it to drive a wide variety of cables without difficulty as the active stage compensates for the cable linearity issues.

The balanced stage has a passive filter after the I/V converter, this makes it highly dependent on the load represented by the impedances of the cables you are using and the input impedance of the power amps.

Balanced can be better if the rest of the audio chain can take advantage of differential drive, all of my amps, headphones and speakers use differential drive.

Not much can be done here except to use low(ish) capacitance balanced cable with linear response in the audio band designed for professional use like the Canare L4-6ES or the Gotham GAC/GAC+ series if you want to spend the money. I would steer clear of the Audiophile stuff for the XLR outputs on the LKS. A preamp in the middle might work depending on quality, I have used a Schiit Mjolnir as preamp with decent results.

LKS decision to use an unbuffered passive XLR output is an unfortunate triumph of audio "purity" over common sense.
The LKS004 is a decently designed unit for most parts but it has quite a few shortfalls when it comes to implementation.

 

[Carlo7]

Bobb, I enjoy reading your posts. I have the Lks 004 amazing creature ! I have about 400 hrs in and ready for transformer and usb tweeks. Did you try ear sd40 yet and what other small things can i do to improve ?
Thanks carlo7

 

[b0bb]

Any pulsar mod on 004 yet ?

Bobb, I enjoy reading your posts. I have the Lks 004 amazing creature ! I have about 400 hrs in and ready for transformer and usb tweeks. Did you try ear sd40 yet and what other small things can i do to improve ?
Thanks carlo7

LKS is starting to address some of the issues such as heat and insulating the USB connector.

I am waiting to see where this will lead, once components are removed from the board the warranty becomes void, the mods I have described until now are reversible and do not require desoldering parts of the DAC.

 

[Tomus4]

Hi,
New opa for MH-DA003: http://allegro.pl/wzmacniacz-operacyjny-dyskretny-os-opamp-dual-i6889250300.html
V5 in the output stage was the best for me (I tried DEXA - in my system was to dry with non control in bass).
Staccato Audio OS crush V5 in all aspects, V5 seems to be dry, non musical compare to Staccato. Best effect after 70...80 hours of warm up.