IcePower ASP1000 - Tweaking/Mods/Upgrades

[noniaster]

I have been trying to investigate what the purpose of the adjustment screw is. After looking on other ac-dc PFC i found out that they have an adjustment screw for changing the voltage.

Can anyone confirm if this is an voltage adjustment screw? If so what will the optimal setting be? high or low?

Just another piece of info about the PFC. I bought 3 used PFC from agreetao.com for 22 usd/pfc + shipping. Nice cheap price compared with buying them new?

 

[john65b]

Damn, I paid $80...what was your shipping cost?

 

[noniaster]

I paid 3 x 22 + 40 in shipping. So 106 usd in total for 3 PFCs. shippng for china was expensive because of the weight (3 x 0.6 kg)

 

[rafikgd]

Output voltage

Modules and case just arrived. Have put them together and checked - both modules working with about 375 volts output, without load. Now thinking how to deal with output connectors: have to be fool-proof hence Neutrick proprietary round powercons make sense, rather than just usual IEC outlet.

Dear Arky,

Did you connected OPS output directly into ICE board power input?

Regards,

 

[arky]

Dear Arky,

Did you connected OPS output directly into ICE board power input?

Regards,

I am using Jeff Rowland 201 monos. However, it is just ICEPOWER ASP500 modules with some JRDG proprietary transformer at signal input, fitted into sexiest aluminium polished enclosures. So I mean - yes, it's just connected the following way: OPS output (385DC) goes directly to 500ASP AC power input. IMPORTANT: DON'T FORGET TO CHECK YOUR FUSE: it should be set up for 240V operations! Polarity does not matter.

 

[arky]

Using PFC with ICEPOWER 1000ASP modules is almost useless.

No idea how PFC will help the audio performance while the SMPS is regulated.

This is the same to argue that any copper wire should sound absolutely similar, which (in real life) is not. We hear the difference and really do not care what is the actual reason. Psychoacoustics is something different to electricity, however sharing the same roots. We only trust our ears.

 

[Julf]

Psychoacoustics is something different to electricity, however sharing the same roots. We only trust our ears.

if you study psychoacoustics, you usually realize that only trusting your ears is not a very good idea...

 

[arky]

if you study psychoacoustics, you usually realize that only trusting your ears is not a very good idea...

You right, brain is also very important.

 

[Julf]

You right, brain is also very important.

And that is the problem. Our brain is far too clever for its own good...

 

[arky]

Nevertheless, people here do confirm they hear difference with PFC modules and their perception all likewise - sound seems more clear and focused. I would assume PFC is working like additional mains filter, which is moreover located distantly from the chassis.

 

[engelheimer]

Altec ring of three circuit

Look for the classic, and elusive Altec ring of three circuit, Neve and others use it.
Built a tube version years ago. No need for a xfrmr...

On your 1000's, do C235/236 run warm @idle?

I've just got my hands on a pair of ASP1000, and I would like to know what could I do to take the most of it.

I already know all the limitations these modules, and I'm also going to give a try with Hypex's UcD with SMPS and HxR, and maybe Coldfire.

Anyway for now I want to take the most of them.

I've read that Bel Canto uses this module in a straight forward implementation, that is, looks like they simply put the ASP100O on a case, add some ferrite chokes, add a small Led that's connected to the connector P3 with maybe some kind of resistor on the pins:
1 PGND Power supply Ground GND
2 Vp2 (80V) Power supply 80V Output

And that they fit a RCA socket and a XLR socket and the only thing they do is to put a switch (supposedly to switch between inputs) that I haven't figured out what exactly is it doing... And that's it!?!?

Wired4 Sound for example as a different approach, looks like they do some kind of component modding (superior grade caps and resistors, and add a input buffer board to solve the low impedance problems of this amps.

JRDG, is the one that I'm most curious about what mods to they do. I've been unable to found out what they do.

Looks like they add a lundahl Line Input and Repeat Coil Transformers and that's all I know..

So all n all, I would like to know your opinions on what could I do to improve this amp (maybe except for components upgrade since this is a 4 layer board full of smd's and I don't think it should be easy to change stuff on it. But if anyone as a good proposition I'm an open minded person, so....)?

One thing I tough to apply on my case was an input transformer, like a Jensen or a lundahl Line Input and Repeat Coil Transformers for galvanic isolation a RF protection on the input signal, and I was also thinking on putting some ferrite chokes, on output to speakers and power supply, also to avoid RF interference.

I've read that the ASPs have very low input impedance, 7kOhms, so that could be a problem when hooking it up with a pre-amplifier.

Especially if you are using a tube pre-amp.

I think, and I'm really not an expert on electronics, that it should have at least a 100kOmh input. No?

One way to solve this problem, at least that is what I've heard, is to use a direct-coupled, balanced, dual FET input stage (input buffer).

The problem is that my electronic knowledge is limited since the stuff that I studied a few years ago (7+ Years) at the university when i was tanking my masters in electrical engineering (Electrical Power systems field) was minimum.

Maybe if I go into my books I might be able to find some kind of literature on input buffers, but I think I would have to study again and remind stuff that I don't usually work with.

I saw a post once @ DIYAudio regarding a project for a balanced dual FET input stage... Do you have any knowledge on the subject? Would anybody recommend the use of such a input stage on ASP 1000?

At the moment I will be using my pre-amp that as the following specs (It's a Electrocompaniet EC 4.5):

Preamplifier section
Single ended operation (gain)0 dB
Balanced operation (gain)6 dB
Input impedance50 kOhm
THD single ended (1.5 V output)< 0.003 %
THD balanced (1.5 V output)< 0.0015 %
Max. input> 10 V RMS
Channel separation (1 V output, 1 kHz)> 90 dB
Output impedance100 Ohm
Max. output Single ended8 V RMS
Max output Balanced16 V RMS
Output noise400 Hz - 30 kHz input shorted
Single ended : 6 µV
Balanced :11 µV

I'll have to check whether it's a good option or not for this power amp...

But I would like to upgrade my pre-amp for, one (DIY or Not) let's say, in the league of a JRDG Capri or Concerto... or let's say a passive pre-amp (like Pass labs B1).... Preferably balanced and with bypass possibility... But for now I'm stuck with my EC4.5 (And I could get easily a CJ PV12)..

By the way, does anybody know where does Krell get from those speaker binding posts? On "low end" krell models they use WBT but on top levels they use binding posts that you usually see on soldering machines!

If only I could find out who makes those Hi-Tech connectors like for example on those evolution 900 series...

Also an other thing, Where could I get good looking cases in rugged aluminum? Like Alcoa Alloy 6061-T6? Preferably In Europe

Cheers,

 

[Boneman73]

Hi! I'm resurrecting this (older) thread. I am interested in the PFC modules - I, like user arky, have Jeff Rowland amps. Mine are the Model 501, using the ICEpower1000asp modules. I believe this thread has answered most of my questions, but I cannot see the pictures that were posted of Arky's PFC's. So - a couple of questions: (1) can someone (arky?) post pictures of the completed PFC unit, and (2) does the PFC module need any fusing or auxilliary electronics for protection? Thank you!!

 

[Zoef]

I have 2 500asp.... was wondering how to configure the lundahl 7902 .....

 

[ddeacon]

Zoef,

Please send me your private email address and I will send you the electrical schematic for the Lundahl/ICEpower interface. I also have some PCBs already made.

Dennis

 

[Zoef]

Just did .

 

[gervit]

Hi, This is my first post but I read and learn from you since long time.
I like audio gear but I am not technical guy.
However, I'd like upgrade my monoblocks MURANO P500II Plus (ASP500/Lundahl 7092 220v input Voltage ) with PFC 500 385, like JRowland PC1. It will be my first little proyect but I need some help.
Can someone show me How do I must do to connect cables from sockets to binding screws of AC/DC module?
Sorry , I know it is so primitive , but...
Maybe I can upload some pics from Murano's if you think will be better.
Sorry if this post hungry to someone and for my poor english.
Thanks to understand.
Gerardo

 

[powderclear]

I have 1000ASP modules, interested to getting case, and LL7902 PCB to get a working amp.

Please send me photos and pricing of the abovementioned components, and whatever else you think I would need.

Thanks!

 

[powderclear]

myoung@polymers-ppi.org

I would like to have the electrical schematic for the Lundahl/ICEpower interface. And please let me know about the pricing of LL7902 PCB's.

Thanks!

 

[hickert]

Help with 1000asp

I can't disclose more in this forum.
Nor can I sell the kits because these are other people's IP
I ve already disclosed too much...............

Artur can you send me schematic to khickert @ gmail

Pls

I have some of these 1000asp and need input buffer to increment gain

 

[gazza49]

input buffer

try the neurochrome universal buffer