[cab]

That's why I've preferred batteries. I'm sure people will be trying this soon with their ncore kits.

I know someone who plans to give it a go when he receives his modules. Perhaps I can persuade him to publish his results here....I believe Bruno has already given his opinion on the matter but undoubtedly there will be those that have to try it for themselves.

[Don_S]

Me too Big Red.  So spill. That is the ony reason I keep visiting this pissing contest thread.

As I recall you have heard an amp or two in your system. 

I'll be interested to hear how well the Ncore's drives your SoundScapes.

[JohnR]

OK, in the interests of making some progress here, some people have been temporarily removed from posting. If this thread gets back on track in the next day or two, we will see if the SS Facilitator cares to be bothered to deal with it again and if so, I'll clean it up again and put it back.

Or, perhaps an NCore owners will propose an Owner's Circle with the standard procedure.

[ChrisPa]

1st post, so here goes
I joined audiocircle because there seemed to be an interesting set of conversations about the ncores (I now own a pair and I've watched the design process from the beginning)

So to start with a comment on one of the questions/comments raised in the thread (it is a questions and answers thread after all)

Re. batteries

The ncores have an extremely good PSRR (power supply rejection ratio) across a very wide frequency range, hence (among other things) they contain high quality discrete voltage regulators on-board (that's what all the leds are doing on the amp). So as a result they are highly immune to psu variations, mains variations and mains cable variations. That's the way they've been designed.

One of the reasons (the prime reason) why batteries have such a positive effect on other designs is because they don't have the same level of supply immunity.

Batteries are unlikely to have a major effect (if any) on the ncores. But i'm sure someone can readily try it out if they want, or if they think they need something more than they get from the stock amp and psu combination

[ChrisPa]

Batteries and low power:

Oh yes, and one of the comments from the designer was that dropping the supply voltage doesn't improve the low power performance. I can't remember exactly but I think it was that the linearity at low power benefits from a higher supply voltage (on a scale of being extremely linear under any conditions), so you get a better '1st watt' with the stock smps than you would if you dropped the supply voltage.

You can always substitute a lower voltage supply if you want (as long as you don't drop below the absolute minimum specified voltage)

[JohnR]

You can always substitute a lower voltage supply if you want (as long as you don't drop below the absolute minimum specified voltage)

Which, in case anyone is wondering, is (+/-) 35 V. (Per the spec sheet.)

[OzarkTom]

Which, in case anyone is wondering, is (+/-) 35 V. (Per the spec sheet.)

So if you go with a 36 volt battery, would that just lower the wattage? Or would you still get 200 watts, which I will never need.

I always hear an electronic glare with any SS amp I listen too, Class A, Class B. Class D, or Class xyz. Some tube amps give me the same problem. Blame my local electric company, that is what I do.

I can listen to the same amp after midnight and most of the glare, not all, disappears. Without the glare, I hear more presence in the air and detail by quite a bit. The vocals floats more magically.

A battery completely eliminates the glare. But if I do leave the charger on the battery while listening, some of the glare appears. Maybe I am just a little too fussy, but that glare is too fatiguing for me after about 10 minutes. I have to shut the system down

[*Scotty*]

OzarkTom, you might be able to do away with the batteries if you built yourself a felix power filter.
I live in a 16 story high rise with over 300 condo units in it and this simple power filter design pretty much eliminated glare and masking of information in my system.
 I have zero listening fatigue, YMMV.
Scotty

[OzarkTom]

OzarkTom, you might be able to do away with the batteries if you built yourself a felix power filter.
I live in a 16 story high rise with over 300 condo units in it and this simple power filter design pretty much eliminated glare and masking of information in my system.
 I have zero listening fatigue, YMMV.
Scotty

I have tried numerous power filters over the years. The glare is masked, but I always have lost some detail and imaging. The battery gives me everything plus more. Battery has always out-imaged the AC line.

[Jonathon Janusz]

ChrisPa, thank you for your posts!  I asked a question in one of the other threads, and your information indirectly got me to an answer with some insight as to why it works.  I had asked about power conditioning ahead of the amps and how this related to the perceived noise floor.  Your information regarding the regulation on the power supply was insightful.

Thanks again!

[JohnR]

So if you go with a 36 volt battery, would that just lower the wattage?

Per the spec sheet, yes - "Available output power depends on supply voltage"

You would need two of those batteries though.

[OzarkTom]

Per the spec sheet, yes - "Available output power depends on supply voltage"

You would need two of those batteries though.

Oops, I overlooked that detail. But now maybe I will order without the switching power supplies. I can always order the HSPS at a later date if I ever need to.

If I was building the Ncores with the HSPS for myself, I would put put the power supplies in a separate box in case a better after-market one came available.

[OzarkTom]

Per the spec sheet, yes - "Available output power depends on supply voltage"

You would need two of those batteries though.

JohnR, I wish I knew more about batteries. Would these 36V Dewalts work? You can get two plus the battery charger for $315.


http://www.ebay.com/itm/2-Dewalt-36-Volt-Lithium-Ion-Batteries-With-Charger-DC9360-DC9000-/251048166781?pt=US_Power_Tools_Batteries_Chargers&hash=item3a73a3057d

[JohnR]

Honestly, I don't know. I'd assume they would work but whether it's a good choice or not... 

[OzarkTom]

Thanks John. I will search for more alternatives.

[Russell Dawkins]

You might also consider the noise factor. Different batteries have their own noise signature. I used to put small caps across the outputs of the NiCads powering my microphone preamps after reading that they also create a HF noise along with their DC. It rides on the DC, that is, it's not perfectly smooth.

You might want to look into that as well.

[analogsa]

Fwiw these guys http://www.veloceaudio.us/lev2/c_prod_v8.html use lithium batteries with the UCD modules and will continue doing so with the Ncores. They wouldn't touch the smps.

[ChrisPa]

Jonathon

Thank you


OzarkTom

It's (more than) well worth giving the stock supply a go. An smps is effectively a class D amp with the objective of only providing DC. An amp (any amp) takes it's power from the power supply (DC) any converts it into an alternating output voltage which matches the alternating input voltage. A power supply (any mains-in dc-out psu) takes an alternating supply voltage and converts it to a DC output voltage that matches it's DC input reference. If the job can be done on an audio signal then it can also be done on a DC reference to create a DC supply. If the amps are that good on AC, then why can't an smps be that good creating DC?

Power vs. supply voltage - yes the output power of any amp is limited by the maximum voltage swing it can drive on its output terminals, and the maximum voltage it can drive is when it reaches the supply voltage. So the higher the supply voltage the higher the power and vice versa

If you want to try batteries then be aware:

- below the absolute minimum on the spec sheet the amps are likely to go into protection mode (shut down). The voltage on a battery drops as the charge goes down it may not be discharged but it may not have enough voltage to keep the amp alive

- Russell is right about different batteries having different noise characteristics, because of having different frequency response characteristics. Batteries are designed/intended to provide DC/low frequency power; the class d amp is asking for (very) high frequency power, at the switching frequency of the amp, probably 0.5 MHz or higher.  So caps in parallel seem an obvious requirement.

- class d amps have/cause an effect known as 'pump up' where they push power back into the power supply. So any supply has to be capable of absorbing/accommodating this power. A battery should inherently be capable of absorbing energy - that's what charging it does - but just be aware that the characteristics of a good supply for class d are slightly different to conventional amps

[Big Red Machine]

  Now we're gettin' somewhere.

Some quick notes from our very fast, and totally unscientific, listening of the Ncores versus the Samsons last night.  There were 6 of us there, Maxcast, Jim, Roscoe, TomS (his amps), me, and Dave from Iowa who came for the show.  JD3 and Mrs. JD3 did hear them, but with zilch for time on the Samsons before they left.

We had mixed reactions to the amps.  We did try to play a few tunes and then switch amps and play the same tunes but the gains were different and memory faded during that switchover.  The amps did get lukewarm as compared to my very cool Samsons which have been on constantly for a month now.  Neither here nor there, just an observation.

The amps were dead quiet as advertised.  I used my cables except for the SC's cuz Tom had the funky Cardas posts which needed spades and I use bananas.  No clicking, no popping, only slight preamp buzz, even less than I get with the Samsons through the speakers.

Most everyone had something positive to say about the amps and felt they were very good in the midrange and perhaps meatier there.  They have tons of bass so no issues there whatsoever.  I felt there was a sheet over the mid to top end as compared to my Samsons but if you had just dropped these in and listened to them for an extended period I can see where folks would fall in love with them.  Really a nice amplifier but I won't be selling my Samsons as a result.  I would like to use them in a second system if I wanted the fun of building them over using tubes in a 2nd system.  Those modules in there are really small.  Way smaller than the photos indicate. 

I'd say more folks liked them than didn't last night.  Very promising and to me about 90% of what I am used to and perhaps some more of some good things in certain areas that only an extended time could tell me.  They certainly would grow on you and you can do waaaayyyy worse than these over-performing little, and I mean little, devils.  Tom snapped an iPhone shot of them lying on their backs on top of the Samsons.  They had about 1/8 the footprint.

[TomS]

Here are those grainy phone glamor shots Pete mentioned, on top of upside down NCores so the right angle AC plugs would fit, and complete with sandbags on them so the cables didn't lift them up to the sky. I'd say not so much Samson, but rather David and Goliath! No one could believe those little things were actually amps. I think Pete has some connectors bigger than them 




Just a few thoughts:
- Thanks so much to Pete and Brenda for having us crazy's over late into the evening of an already long day at the show. This was really a lot of fun and they were all great people to spend time with. This is what the hobby is about for me, as well as others' perspectives and advice on how to make your system sound better.
- I've been to Pete's place a few times over the years, and while it always sounds good, last night his room, the TRL gear, and especially the SS8's sounded (and looked) fantastic! A must hear for sure.
- Pete (and others) gave honest thoughts of the comparison. No hiding behind keyboards here. It was refreshing and as it should be so we learn. Respectful but candid.
- This was VERY informal, as Pete said, maybe half a dozen tracks switched without level matching, a little different cabling, out of practical necessity, etc.
- The Ncores arrived Thursday morning and I assembled them Thursday afternoon while on conference calls. No voodoo parts or funny dust inside them. So, not much play time, but for them I don't think it matters. They sound good cold out of the box at my house and in Pete's system.
- For me, this actually said as much about how very, very good the Samsons are. I had not heard them before (I do own a Dude), but had been trying to find a pair to listen to and/or buy while I had the NCores on order. Any one who snags a pair is in for a treat.
- The amps are probably much more similar than different and both in a special league. Both have great clarity, transparency, and naturalness, and with the SS8's in that room, great bass, though different from each other which Pete knew right away as he knows his system inside and out. It was the first time I'd heard the NCores truly full range as my Abbeys start a natural roll off at 100hz. I'm not sure which I preferred but they were both excellent on their own.
- Ultimately, I think there were some preferences both ways, not absolute, but it was sort of splitting hairs on 2 really great sets of amps.
- Lastly, Jim and Pete shared some insight about these sort of "shootouts" (with speakers) and how little they really mean if you're not in the room and how things can go wrong (with amps, drivers, cables, etc), giving people the wrong impressions even to those who were there. Yet, the forum posters (there or not) still post away and infer things that didn't really happen. Just take it for what it is, nothing more.

This wasn't a shootout to me, rather friends having a good time listening to music and  trying to learn something about their gear. Both the Samsons and Ncores can show it all to you for fairly reasonable money compared to some of the big boys that don't, and are also as quiet and reliable as can be.

Listen for yourself, in your own space, and enjoy.