Introducing the Matrix M-Stage HPA-3U and HPA-3B, review to follow!

[raoultrifan]

@Atgm1, just change the two power regulator from 7818/7918 to 7815/7915. Two 1 Ohm/5 Watts resistors might get added either between transformer to the bridge rectifier, either from the bridge to the big caps (to lower a bit the input voltage to the two regulators). After this mod, double check the temps of the regulators, just to be sure everything;s fine; of course, check the voltage rails and stability too. Now you can install the Vivids and enjoy the added microdetails

 

[Atgm1]

@Atgm1, just change the two power regulator from 7818/7918 to 7815/7915. Two 1 Ohm/5 Watts resistors might get added either between transformer to the bridge rectifier, either from the bridge to the big caps (to lower a bit the input voltage to the two regulators). After this mod, double check the temps of the regulators, just to be sure everything;s fine; of course, check the voltage rails and stability too. Now you can install the Vivids and enjoy the added microdetails

Tell me, will it not be easier for me to install muses03? for me it’s not so much the microdetails that matter as the realism, the width and depth of the scene.

 

[raoultrifan]

I don't think so, you need 4 of them (so, very expensive) and also lot of DIY works to adapt them from single SOIC to dual-DIP8.

 

[Atgm1]

I don't think so, you need 4 of them (so, very expensive) and also lot of DIY works to adapt them from single SOIC to dual-DIP8.

besides power regulators, is it necessary to change two resistors? I can't even imagine where they are. I found the power regulators, but I do not want to interfere in this technological work of art.

 

[raoultrifan]

There are no resistors to swap, but the voltage drop on the 2 regulators will be 3V higher. So, ideally would be to lower the dropping voltage with few volts, if possible. I was actually cutting the traces that got from transformer to the bridge, and added couple of resistors on the back of PCB.
However, if you'er not comfy with such mods, please ask somebody else to do them or simply swap the regulators and care not about the resistors anymore.

 

[loserica]

Tell me, will it not be easier for me to install muses03? for me it’s not so much the microdetails that matter as the realism, the width and depth of the scene.

Burson V6 Vivid add realism, width and depth (not just microdetails). Muses 02 for example is not able to enlarge the scene so much how it does Burson.

 

[Atgm1]

There are no resistors to swap, but the voltage drop on the 2 regulators will be 3V higher. So, ideally would be to lower the dropping voltage with few volts, if possible. I was actually cutting the traces that got from transformer to the bridge, and added couple of resistors on the back of PCB.
However, if you'er not comfy with such mods, please ask somebody else to do them or simply swap the regulators and care not about the resistors anymore.

and if you do not turn on the gain at maximum gain, will the opamps still have 18v?

 

[raoultrifan]

If you never used the soldering gun and you're not comfortable doing the above mods by yourself, then I do not recommend you to open up the HPA amplifier.

After all, the main difference when swapping the original LME49860 with SS V6 or MUSES02, OPA1652, MUSES8920 etc. is lowering the background noise when using very sensitive cans, especially IEMs.

 

[mikaelmark]

I have a DIY Lovely Black Cube (completely made by myself), that are mostly the same architecture. It have the V6 Vivid and I replaced the LM317 and LM337 to Sparko 7915 and 1117-15 discrete voltage regulators (+-15 Volt).

The only thing I was suggested by Sparko to do, was to remove the two 100 Ohm and shorting the 1K1 Ohm resistors. It work´s like a charm! Later, I will compare the V6 Vivid and Classic to Sparko SS3601/2, and also compare my DIY to Burson Fun.

 

[Atgm1]

friends, are these opamps suitable for our amplifier?


https://eu.mouser.com/ProductDetail...=sGAEpiMZZMtCHixnSjNA6POfvxHi7ti2NVFSnl25bd8=

https://eu.mouser.com/ProductDetail/Texas-Instruments/OPA637AP?qs=wgAEGBTxy7nfgz4EbApFvQ==

 

[raoultrifan]

Not really, you need dual opamps, not singles.

 

[Atgm1]

Not really, you need dual opamps, not singles.

I want to try installing two on each channel.

 

[raoultrifan]

Well, you might try the OPA637 in dual config, just be sure they are not overheating. Also, measure the output DC (headphones plug).

I still think that lowering the internal voltages to +/-15V is a good thing. I personally destroyed couple of output resistors while doing tests with sinewaves and max. volume, so definitely this headamp was not designed to run at max. volume continuously. Lowering the voltages will help with any possible overheating, while opamp swap possibilities will increase a lot (30V opamps are much more than vs. 36V opamps).

 

[Atgm1]

Well, you might try the OPA637 in dual config, just be sure they are not overheating. Also, measure the output DC (headphones plug).

I still think that lowering the internal voltages to +/-15V is a good thing. I personally destroyed couple of output resistors while doing tests with sinewaves and max. volume, so definitely this headamp was not designed to run at max. volume continuously. Lowering the voltages will help with any possible overheating, while opamp swap possibilities will increase a lot (30V opamps are much more than vs. 36V opamps).

I use a DAC (audinst HUD DX-1) in conjunction with the m-stage. Does it make sense to install burson in my audinst?

 

[raoultrifan]

The first 2 opamps are from the I/V stage, but are SO8/SOIC, so you really need to troubleshoot this a bit to install SS V6 opamps. I would say that it's kinda impossible. Instead, you might want to replace the two MUSES 8920 with two OPA1612 and the LPF opamp MUSES892 (DIP8 socket) to replace it with SS V6 Classic/ or Vivid.

However, in the end I don't think there will be any audible improvements in any way, but there will be fun to do these mods for sure.