[zxzxzx207]

Right now the top is acrylic. ITO glass is conductive glass that I will use to replace the acrylic. Help reduce interference not that there is any now tbh but just smth nice to have.

 

[vintageaxeman]

I would like to use that on the top of my modded cd player. Is it easy to obtain? Where are you getting yours from please?

 

[zxzxzx207]

Not that easy to find, some science equipment suppliers can sell it. I had to go trough some of my contacts from work as they normally don't do single orders. For reference the ITO top for this was 50USD. It is not cheap especially for one off pieces.

 

[wrexel]

Hi I have a Lovely Cube which has been gathering dust as I haven't been listening to CDs for some time and was thinking of connecting a streaming source to it. Would it make sense to connect a USB DAC to it and use my phone to stream music to it and if so how would I connect into the line ins for the Lovely Cube? I would be using a HD600 mostly for listening. Thanks in advance!

 

[KonstantinN]

Have tried negative feedback mod for the amp. It is a game changer for low impedance headphones! My 16 ohm 70mm driver cans have moved to a higher league Dynamic range and transparency have been improved dramatically. And the mod is very easy to implement - you need to desolder one end (the one that is closer to the back side of the amp) of 4.7k resistors near the opamp and connect it to the middle point of the output 10 ohm resistors.
Original blog post: https://blogs.yahoo.co.jp/be_kow/53647233.html

Author implements the mod on back side of the board, while it can be done of front side also:

Happy modding!
Native OPA2134 sounds very detailed in such configuration. OPA2604 adds more bass Other opamps may require 10pF capacitors across 4.7k resistor or setting the gain to 0db.

 

[mikaelmark]

This week I finally finished my LBC -amp, as I replaced the standard voltage regulators LM317 and LM337 for Sparkos discrete 7915 and 1117-15 (+- 15 Volt DC). I used Silocon pads between the regs tabs and the DIY heatsinks, made of a strip of aluminium connected to the enclosure, using nylon M3 screw.

https://sparkoslabs.com/discrete-voltage-regulators/

Paired with Burson V6 Vivid, Mundorf 10.000uF M-Lytic, Audyn True Copper (huge size) bypassed with Russian FT-1 Teflon, Holco H4/PRP9372 1 Watt resistors, Polystyrenes, Elna Silmic, Panasonic FR, BYV-27, PCB with extra thick copper, OFC wiring, matched transistors BD139/140-16 and a Dale 24 step volume attenuator.

Next week I will do a comprehensive A/B-testing against Burson Fun, V6 Classic and Sparko SS3601 and promise to do a review.

 

[mikaelmark]

Here´s a link to the review: https://www.head-fi.org/threads/bur...l&utm_source=watched_thread_reply_messagetext

Another thing; Someone suggested shorting pin 5 and 8 (Trim and NC) for single OpAmps, such as OPA134 and OPA627, for DC Offset.

Can this mod be applied for any single OpAmp, if they´re solderet to an double single to dual -socket in the LBC, also discretes? And what are the advantages?

 

[mikaelmark]

As the Power supplies cap´s C103, C104, C203 and C204 in the output stage should be 470uF as standard, and can safely be increased to 1000uF - do anyone know if it´s ok to increase them to 1500uF?

Or is that too much? Pros and cons?

 

[KonstantinN]

As the Power supplies cap´s C103, C104, C203 and C204 in the output stage should be 470uF as standard, and can safely be increased to 1000uF - do anyone know if it´s ok to increase them to 1500uF?

Or is that too much? Pros and cons?

The more, the better. While real improvement of the ripple is negligible after some capacity.

 

[mikaelmark]

The more, the better. While real improvement of the ripple is negligible after some capacity.

Thank´s for your quick reply!

Some people stetes higher values for components will generate more noise to the sound (same for faster rectifier diodes).

As I have some 1500uF Panasonic FR, I may use them for this position for my latest insanely modded LBC, with SparkoS SS3602 discrete OpAmp and Intertechnik Audyn True Copper Cap for DC coupling. But I´m a bit confused about those caps, as the manufacturer assert that due the construction of those caps, they should only be used in crossovers for spekers, and for DC coupling one should choose their MAX sibling model. But what can happen - it should not be a safety risk due to the low signal voltage and for me the sound is fine?

Any thoughts about this?

 

[KonstantinN]

Some people stetes higher values for components will generate more noise to the sound (same for faster rectifier diodes).

Too generic statement. My answer was about specific components (capacitors) at specific place, playing its role in specific function (Low frequency filter).

Intertechnik Audyn True Copper Cap for DC coupling. But I´m a bit confused about those caps,

I do not know this manufacturer and never saw a data sheet for the mentioned capacitors. Therefore - no comments from my end.

 

[mikaelmark]

I´ve earlier tested and reviewed the Burson V6 in the BCL, that were quite good, and a couple of months ago also SparkoS SS3601/2 - and those were truly fantastic in my BCL amp!

Now, I´m up for testing the NewClassD and soon also from Orange. This far, the NewClassD has only been fitted in a AK4399 DAC, and it seem´s very promising!

But one small thing is confusing me a bit; Lars Clausen from "Dexa", that were kind to provide me with the NewClassD discrete OpAmp, suggested me to fit some bipolar Mylar caps to each power pins as a complement to the original electrolytic 240uF in the schematic. This should favor the 20kHz and below 200Hz sound. He told me those caps should preferrably be 1nF or at least 0,33uF but 1uF are also ok! But 0,1uF and 0,47uF are not ok!

Why?? Can someone please describe this for me, as it do not seem´s logical!?

However, yesterday I soldered some 2,2uF Vishay KP1830 (all measured 2,1uF) to each V+ and V- pin to ground, totally four caps for single discretes. And to my ears, I believe the sound are now better than before.

But when I gave him the BCL schematic, he told me it seems to already having enough stabilization caps to ground.

 

[mikaelmark]

I´m testing several discrete OpAmp´s for my portable LBC (with first generation NiMh 16VDC/2Ah battery pack), all with good results. And the batteries are drained to about 7VDC, then the volume will be a lot lower and if going below the OpAmp´s working voltage, it will also be distorted. Now, I wonder about some things:

1. As the input power is directly connected to the +/-15VDC output at the voltage regulators LM317/LM337 to minimize the power draining from the battery, so also the voltage reg´s and the two big power power filter cap´s and of course also the rectifier diodes, will not be used - may the voltage reg´s draw any mAh current backwards, altough there are no draining component at this direction other than the unused power stage. Maybe it´s best to remove the whole power section (by removing the voltage reg´s or cut the PCB´s copper conductor´s for the output pin´s)?

2. Should the two big filter cap´s (with original value 4700uF) be used altough the amp is running by batteries, or will the OpAmp be satisfied without them powered in realtime directly from the batteries?

3. Can I safely remove all the three (or any of them) LED´s for the amp, to minimize the battery draining?

4. As those discrete OpAmp´s will accept 24VDC, will it be fine if raising the batteries voltage to something between 18 and 24VDC?

5. With above in mind, should the amp be better if replacing the NiMh with Lithium, such as dynamic and transient speed etc?

 

[mikaelmark]

Some people told me this LBC -amp will not have any local negative feedback from the output stage to the input, so it will have a high DC Offset and also have insane output levels and maybe also high distortion!

Any thought about this and maybe what to do about it/how it can be fixed?

 

[mikaelmark]

I just get an recommendation from SparkoS, to solder a 22pF NPO/COG film/ceramic cap in parallel with each 4K7 resistors R102 and R202 for negative feedback to ensure stability for high speed, high performance OpAmps, such as discretes (where there´s a risk for oscillation).

Those will be connected to 1 - 2 and 6 - 7 (-In/Out for each channel).

Don´t know if this mod will fix the problem with the local feedback/DC Offset, but it should not affect the sound quality as the bandwith will be around 1,5mHz.