New naim AMP for custom build speaker

[Mike-B]

@Mark84

Double check your driver wiring too, sometimes the crossover requires a driver wired in reverse polarity. Troels wrote a piece about this.

I believe it normal in most cases to wire a driver in ‘reverse’ (+/-) when its in series with a single capacitor.
I’ve always use a SPL meter & freq tone to check all my self built speakers or serviced speakers,
and would not be happy to not do this.

I checked the Faital3WC-10 circuit diagrams & see the tweeter is show as wired +/+
I don’t doubt Troels expertise, but I do question this. Then when looking at the frequency response graph, there is no sign of a suck-out the the crossover region, so it must be right.

[Mark84]

The midrange however, is inverted polarity on this design.

There’s a page written about why it’s required with certain crossover topologies. Not far down the updates section. Although I’m sure you already know about why it’s done. Bringing the drivers back into phase if I understand correctly.

I do hope @Retm gets this sorted out. Something sounds fishy.

[Retm]

Hi Mike

It‘s exactly the same. If I put the balance to 10 on right or left doesnt matter.
It sounds way better (it‘s noticeably more „open up“ than when I put it on 0 (both). Off course I listen on setting 0 as I have 2 speakers…

[Retm]

@Mark84

irstly, I think you need to check your crossover very very carefully and make sure you haven’t made a mistake. A channel imbalance tells me you may have something wired wrong. It’s easy to do.

Congratulations on the purchase of the Atom.

Your speakers still need to break in but by the sounds of it, you definitely need to change the tweeter resistor. They should not sound harsh.

Double check your driver wiring too, sometimes the crossover requires a driver wired in reverse polarity. Troels wrote a piece about this. It is a common error to miss this.

Thank you Mark!
I checked the crossover real quick and everything looks alright. Will check in more detailed again in an hour or two and report back.

Yes, you are right. We have an inverted polarity on the midrange driver

I will double check that later, but i think I did it right… will report back!

Thanks guys!

[Retm]

@Mark84

The midrange however, is inverted polarity on this design.

There’s a page written about why it’s required with certain crossover topologies. Not far down the updates section. Although I’m sure you already know about why it’s done. Bringing the drivers back into phase if I understand correctly.

I do hope @Retm gets this sorted out. Something sounds fishy.

I see! I‘ll check everything and report back guys! Interesting topic… i learnd quit a bit from you two now! (@Mark84 @Mike-B)

[Mike-B]

Oh OK it looks like I misunderstood what you were saying with … “The sound dramatically improves again, if I put the balance (in the audio settings) to 10 on one speaker”

[Retm]

No i think you didnt
Let me make it clear:

It sounds good if I have it on setting 0 with 2 speakers playing music. But it sounds less open up.

If I put it on setting 10 (left or right doesnt matter) it sounds way better. The sound is more open up… and more lively but oc just one speaker produces sound.

So if i would only have 1 speaker:

Setting 0 would sound inferior to setting 10.

[Retm]

Update:
driver-cables are all connected correctly on the driver itself and also the crossover are exactly made as shown on the plan from Troels. …

Hmmm what could that be ? Any other ideas?

[davidhendon]

Bottom line is that two speakers sound worse than one, which is unusual. So it’s likely a speaker problem.

I would try reversing the polarity on one whole loudspeaker. What does that do? It should make things much worse with both connected.

[Retm]

Guys its ALL GOOD !

I found the „wrongdoer“…

After checking the drivers and crossover,
I connected just the right speaker on the right channel and tested the balance settings again.

Here is what I found out:

• balance Settings to 0 = speaker is playing as usual
• balance Settings to +10 = speaker is playing but louder! (Just a slightly increase in volume which I interpreted in „more open up“…
• balance setting to -10 = speaker is still playing!!! But only in the deeps… no highs…

Conclusions

The balance Wheel does not behave like an analog balance wheel (for example the an old amp I had first (yamaha))
Even with setting -10 the speaker is playing but only in the lower frequencies… on + 10 the volume just increases… thats what I interpreted as „cleared up…“

Sorry for the confusion!!!

@Mark84 I will mount the R1 alternative as soon as I can and test it out again
Did you change the R1 back to one with lower Ohm, after burning in?
I think I should glue the front panel with the drivers to the cabinet oneday… sure that is even better for the sound isnt it? But than I can’t make anymore changes to the crossoverboards…
I‘ll do this task when I‘m happy with the sound.

• cheers
  Reto

[davidhendon]

Yes I suggest gluing is not something to do this weekend at all. It will make almost no difference to the sound quality anyway, but stop you from fixing any problems.

[davidhendon]

@Retm

The balance Wheel does not behave like an analog balance wheel (for example the an old amp I had first (yamaha))
Even with setting -10 the speaker is playing but only in de deeps… on + 10 the volume just increases… thats what I interpreted as „cleared up…“

This doesn’t sound right to me at all…

[Retm]

you are absolutely right!

Do you think it doesnt effect the SQ? So I could just leave it like that?? Than I wont have to brake the cabinet if I would like to change anything in the future.

[Retm]

I found that very strange to! Just tried it out with my left speaker! Exactly the same behavior…

Even on -10 the speaker is playing very quitley and without highs…

On +10 just increased in volume…

I’d like to get in contact with Naim Support to make this clear! I dont want to spread wrong informations… do we have a person which I can tag here in this topic? If not I‘ll us the contact form from Naims website.

Reto

[Suedkiez]

Maybe @NeilS can give some insight?

[NeilS]

I’m not too sure on the Atom/Nova etc. But the balance control arrangement on the green screen range doesn’t work quite the way you’d expect, so it’s likely the Atom is similar.

I’ll check out next week.

Regards
Neil.

[Mike-B]

This post from Steve Harris might help …

Atom balance incrememts

Hi @CrystalGipsey, On the Uniti range of products the balance feature uses a constant power system. Primarily, as the stereo position is offset, the acoustical energy in the room stays near enough the same. This is different to a traditional ‘pot’ balance control where the acoustical output changes depending on position of balance control. As for steps it’s a mix of .5, 1dB and even larger steps which is programmed into the analogue volume control and any fractional part for the constan…

[davidhendon]

I totally missed that post first time round.

[Mark84]

@Retm i think it best if you just keep it simple and get back to basics. Stop playing with the balance control.
Does it sound normal?
Do you get a stereo image and a soundstage?
Does it sound like the sound is in phase?

Everything might just need some time to settle in.

In response to your earlier question, I adjust my tweeter a few times over the first 6 months. I try time with all the options at first, and usually choose the highest resistance as they tend to sound bright when new. Then once broken in this may need to be changed again depending on how much everything changes.

You need to make sure you always have access to the crossover. You never know when you might need to or want to change something.

Keep us posted.

[Retm]

Hello Everyone

let me quickly update you guys.

Since I received the Atom and the NAC A5 cables (4m btw) I have listend to music for many hours… (currently half of the week in homeoffice= 7h music during the daytime.)
And during the evenings a few hours almost every day. So quite a few hours of music on the Atom, NAC A5 an the speakers (the speakers have way more since I have them sind the mid of December).

I tried a lot with speaker placement, speaker height, the old speaker cables again, tried many settings on the SVS Subwoofer, bought isolation feet for the subwoofer, and so on.
I haven’t tried the higher R1 resistor yet! Will do that tomorrow.

I have to say: I am just not really happy with the system… (yet)

In the beginning I though I noticed a difference from the Vincent SV500 to the Naim Atom. Maybe that was just imagination or there really is a small difference… But the sound is still not really where I would like it to be…
Today I switched the amps again to my ears the Vincent sounds warmer and has way better bass.

The Atom on the other hand has the ability to stream and is just so convenient! The lacking of bass can be compensated to a certain level with the subwoofer though.

• What i noticed If there is no music playing I can hear a the speakers very good! There is a background “buzz”, “sum” Idk how to say this in english.

What am I missing:

I don’t really get a sound stage… it doesn’t excite me…it sounds restrained.
It’s just listening to music… not really special.
I can exactly tell you where the music is coming from (even which speaker is playing). I don’t get that 3d (sounds stupid) effect at all when listening…
The sound is not “in the room” its at the speakers (hope you understand what I mean).

My room is not very good for acoustics… here is a picture (i don’t have any room treatments. My better half does not want them in the living room )
Do you think thats the only reason the sound is so “borring”?

I also have a big mess with wires and every powercord goes to the same powerstrip.
Do you think this has something to do with my situation?

My powerstrip goes around half of the room (I don’t have power where the speakers, amp, TT are). So the cord on the powerstrip is 10m long. The powerstrip was maybe 10dollars or less…

I saw some dedicated power strips for hifi system but they can go up to thousands of dollars…

Also my subwoofer cable is 20m long… the subwoofer is 1.5m away from the atom. (I just had this cable left…)

Also the vincent powercord for the Phono Preamp is making noises very loud. If I tap it it stopps for a few minutes.

I don’t want to sound disappointed but maybe I am a bit… maybe I’ve just expected too much for my budget.

I would just love to have music wich floats in the room, makes fun while listening to and envolves me so that I automaticly move my feet to the sound

What would you do? Any ideas what else I can try?
Wait longer for more “burn in”. Buy power strip and other cables?

I’ve already written half a novel… sorry for that!

Many thanks guys!