I just just got VTV Purifi based Monoblocks with VTV buffer and Sparkos 2590 about 2weeks back. The built quality and customer service was really good. Have put in about 200 hours on them. Still waiting to get the desired refinement, though the sound is not bad, still not to the level I am expecting.
Does anyone has experience about burn in Period of these Amps.
I am sure they will sound extremely good after full burn in as Nad and so many other companies are using their Modules.
Does anyone has experience about burn in Period of these Amps.
I am sure they will sound extremely good after full burn in as Nad and so many other companies are using their Modules.
I don’t know about the break in, but if you’re not getting the sound you’re looking for, consider changing the Sparkos out for something else (not saying there’s anything wrong with it, but there might be something you like better). I believe the input board can accept any DIP8 op amp (consult with VTV first), so you’ve got a multitude of chips to try.
I owned a pair of Nord NCore NC500 monoblocks which had a similar input buffer. I started out using Sonic Imagery 994 Op Amps, and eventually got a set of Sparkos SS2590 Op Amps.
I put a couple thousand hours on the Sonic Imagery op amps and noticed incremental improvements (mostly to the imaging and smoothness in the upper few octaves) until 800 to 1000 hours, but they still sounded a bit sterile to me.
The Sparkos op amps took a few hundred hours to settle in, but the rest of the amp was already well burned in. So I'm not sure how much is the input buffers or other parts of the amp. The Sparkos op ams were a bit smoother sounding, but a bit less detailed. The difference was fairly subtle, but I preferred the Sparkos.
I sold tthe NCore amps last year and bought a class A-A/B amp (Parasound JC5) which I preferred over the NCores for it's richer, more involving sound. I've since gotten much more into DIY and replaced the speakers I had (GoldenEar T2+) with open baffle speakers. I've also built two pair of monoblocks - a class A F5 Turbo and a chip amp based on the Neurochrome Modulus-286.
I'm planning to give class D another try since my system has completely changed since I had the NCores. I have a pair of 1ET400As sitting on my workbench and am working on a buffer design. I'm probably going to do a few different buffers with at least one tube based to see how this affects the sound.
I put a couple thousand hours on the Sonic Imagery op amps and noticed incremental improvements (mostly to the imaging and smoothness in the upper few octaves) until 800 to 1000 hours, but they still sounded a bit sterile to me.
The Sparkos op amps took a few hundred hours to settle in, but the rest of the amp was already well burned in. So I'm not sure how much is the input buffers or other parts of the amp. The Sparkos op ams were a bit smoother sounding, but a bit less detailed. The difference was fairly subtle, but I preferred the Sparkos.
I sold tthe NCore amps last year and bought a class A-A/B amp (Parasound JC5) which I preferred over the NCores for it's richer, more involving sound. I've since gotten much more into DIY and replaced the speakers I had (GoldenEar T2+) with open baffle speakers. I've also built two pair of monoblocks - a class A F5 Turbo and a chip amp based on the Neurochrome Modulus-286.
I'm planning to give class D another try since my system has completely changed since I had the NCores. I have a pair of 1ET400As sitting on my workbench and am working on a buffer design. I'm probably going to do a few different buffers with at least one tube based to see how this affects the sound.
Thanks Jaytor & Diomedian for your suggestions. Now after 250/260 hours I think Sound is getting better. Earlier bass was boomy and images were a bit hazy. Now bass has tightened and images are well defined with very big sound stage. But still I feel the sound is bit too much on smoother side and that could be because of sparkos and my system being already smooth. I use McIntosh C-52 Pre amplifier and Cardas Clear cables.
VTV Warren prefers Sparkos and many other on various forums prefer Sparkos. But no harm trying Sonic Imagery if I don’t get satisfactory results. May be another 100 hours should be ok before I decide to try another one.
Would you advice to try Hypex stock buffer that comes with Purifi module. Or is it not worth trying.
VTV Warren prefers Sparkos and many other on various forums prefer Sparkos. But no harm trying Sonic Imagery if I don’t get satisfactory results. May be another 100 hours should be ok before I decide to try another one.
Would you advice to try Hypex stock buffer that comes with Purifi module. Or is it not worth trying.
The stock buffer uses good quality op amps so may be slightly purer sounding than the Sparkos, but the quality of the 12v regulators is probably not as good as the buffer you are using, so it's difficult to predict. I haven't personally heard either.
I am designing my own buffers because I'm building monoblocks and I want to experiment with tube based front ends.
I am designing my own buffers because I'm building monoblocks and I want to experiment with tube based front ends.
How to properly wire a SMPS600N400 to the FE-02 control board included in EVAL-1?
This is my attempt with my limited understanding of the mechanics.
One thing that is confusing me, is that 600N400 specifies no VDR- output like in the SMPS1200A400. But since pins 4 and 5 are anyway connected in the FE-02, can I survive without the VDR- output from 600N400 and using the HV- for both pins 4 and 5...?
(My ambition is to build a monoblock amplifier using a SPMS600N400 and a single FE-02)
This is my attempt with my limited understanding of the mechanics.
One thing that is confusing me, is that 600N400 specifies no VDR- output like in the SMPS1200A400. But since pins 4 and 5 are anyway connected in the FE-02, can I survive without the VDR- output from 600N400 and using the HV- for both pins 4 and 5...?
(My ambition is to build a monoblock amplifier using a SPMS600N400 and a single FE-02)
Actually the main problem for using SMPS600N400 seems to be that the VDR output of the SMPS600N400 is specified as between 17 and 17.5 VDC. The specifications for FE-02 say it would accept a maximum of 16.5 VDC input on the VDR pin.
Could I somehow reasonably drop the VDR output voltage by 1V ��
Could I somehow reasonably drop the VDR output voltage by 1V ��
Get some really god regulators - this will also probably increase the SQ of the whole unit.
If 15V is enough and 0,5A, this will take even 20V:
LT3045-M Ultralow-noise (0.8mVrms) LDO linear regulator 0V-15V - 500mA (1V Step) | eBay
//
If 15V is enough and 0,5A, this will take even 20V:
LT3045-M Ultralow-noise (0.8mVrms) LDO linear regulator 0V-15V - 500mA (1V Step) | eBay
//
The output from your tube power amp will be much too high so as a minimum you need an attenuator with 2 resistors per channel.
Also note that the tube power amp will be much less linear than the Purifi is, so you will feed a very clean amp (the Purifi) with an already distorted signal, which seems not a sensible way to proceed.
If you really want unadultered sound, don't use the tube thing, but go directly from your preamp or DAC to the Purifi with as little in between as possible.
Jan
I just heard that Purifi is coming out very soon with EVAL2 for mono application with their own Input buffer. That may be much better than these third party buffers. But I am not sure till evaluated. Some how I am not very satisfied with the results from my Input buffer and Sparkos.
You might also consider the Neurochrome buffers.
Purifi 1ET400A / Hypex NC500 Input Buffer – Neurochrome
These provide a good opamp solution but also allow for higher performance voltage regulators. They are a bit more expensive than the Purifi mono buffers are likely too be, but are currently available.
I wonder if Purifi will offer this new EVAL2 as a standalone board or if you will have to buy with the amp modules.
Purifi 1ET400A / Hypex NC500 Input Buffer – Neurochrome
These provide a good opamp solution but also allow for higher performance voltage regulators. They are a bit more expensive than the Purifi mono buffers are likely too be, but are currently available.
I wonder if Purifi will offer this new EVAL2 as a standalone board or if you will have to buy with the amp modules.
That would be very cool. Any ETAs ???
Someone else posted that they would be coming out with their own SMPS, but haven't read anything since that post.
Ghent Audio indicated they would be coming out with cases within a month but I don't see anything on their website yet.
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Ghent Audio Purifi EVAL1 Cases
Just got an email from Ghent Audio.
Their EVAL1 cases and harnesses will be available Oct. 27th.
There is enough space in the case to use the Hypex SMPS1200 or the SMPS3K.
ghentaudio --- Purifi EVAL1 Stereo case-kit
ghentaudio --- Purifi EVAL1 Stereo Harness
Just got an email from Ghent Audio.
Their EVAL1 cases and harnesses will be available Oct. 27th.
There is enough space in the case to use the Hypex SMPS1200 or the SMPS3K.
ghentaudio --- Purifi EVAL1 Stereo case-kit
ghentaudio --- Purifi EVAL1 Stereo Harness
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I was trying to simulate the discrete OPAMP voltage regulator outlined in the EVAL1 manual to understand it better:
https://tinyurl.com/y4r5t7hf
However I ended up with a problem: in the simulation with a supply voltage of 18.6V the output voltage is 17.85V (this is now just the +VUNREG side).
According to the EVAL1 specs we should get the 11.4V to 12.6V that 1ET400A requires with a +UNREG input between 16.4V to 25V.
Any idea what I might be doing wrong in the simulation? (Here is the original schematic
https://tinyurl.com/y4r5t7hf
However I ended up with a problem: in the simulation with a supply voltage of 18.6V the output voltage is 17.85V (this is now just the +VUNREG side).
According to the EVAL1 specs we should get the 11.4V to 12.6V that 1ET400A requires with a +UNREG input between 16.4V to 25V.
Any idea what I might be doing wrong in the simulation? (Here is the original schematic
Since last 4 months Ghent is saying next month. In his last mail he said Next week which is the current week. Not sure if they have posted on their website as yet.
Purifi should offer these EVAL2 buffers boards for those who already own Purifi amplifier modules. They shouldn’t be deprived of this option.
See Post #693. They updated their website a few days ago.
https://www.diyaudio.com/forums/class-d/347137-brainstorming-purifi-1et400a-amps-70.html#post6382730
You can ask them. Kim Nordtorp Madsen told me that the SMPS is real, it has a mosfet bridge, it will be also regulated on the main power, and that it is still under development and thus no ETA can be given. And because of this anything could change even though I do not see how they would give up features that would put their product above the competition.
