NAD C 298 Power Amplifier With Purifi Eigentakt Amplification

[decooney]

Hi, new member here. Found this C298 thread. Registered today. Reading pages of posts about auto-sense issues, firmware updates, and spec measurement posts, would love to learn more about how it "sounds" in comparison to other good Class A/AB amps anyone has compared to in some serious listening sessions [in your systems]. I'm kinda looking for a 2nd amp to rotate in once in a while to give my mono tube amps a rest. Most interested in the C298 for its expansive sound stage, depth, smoothness, and revealing midrange presence this amp seems to present. Found the C298 reading about the Purifi modules, and what NAD has done so far. Nice. This thread here seems to go more in-depth than what I've found on any other forum site, credit to all of the helpful forum members here. Thanks!

Maybe a leap to ask, has anyone here tried running the NAD C298 amp paired with a great tube preamplifier on the front end yet? Sound?

 

[muslhead]

uh oh

 

[Aventador_SVJ]

Hi, new member here. Found this C298 thread. Registered today. Reading pages of posts about auto-sense issues, firmware updates, and spec measurement posts, would love to learn more about how it "sounds" in comparison to other good Class A/AB amps anyone has compared to in some serious listening sessions [in your systems]. I'm kinda looking for a 2nd amp to rotate in once in a while to give my mono tube amps a rest. Most interested in the C298 for its expansive sound stage, depth, smoothness, and revealing midrange presence this amp seems to present. Found the C298 reading about the Purifi modules, and what NAD has done so far. Nice. This thread here seems to go more in-depth than what I've found on any other forum site, credit to all of the helpful forum members here. Thanks!

Maybe a leap to ask, has anyone here tried running the NAD C298 amp paired with a great tube preamplifier on the front end yet? Sound?

The C298 is a very good power amplifier and has high sound quality, backed up by very good objective measurements.

It is unlikely that anybody on audio science review will recommend a tube preamplifier as all this will do is add distortion to the sound.

 

[Kal Rubinson]

Maybe a leap to ask, has anyone here tried running the NAD C298 amp paired with a great tube preamplifier on the front end yet?

I must admit that it never occurred to me.

 

[decooney]

...It is unlikely that anybody on audio science review will recommend a tube preamplifier as all this will do is add distortion to the sound.

Oops wrong forum I guess. And, Exactly. I like a little bit of distortion design in the right places. That's the whole point, and what really good tubes can do. If done well it can offer nice second-order harmonics, which can be quite musical.

Coming from Class-A/AB solid state and Tube amps past 40+ years, some of the best measuring pure solid state amps in my own systems can tend to be very boring and un-engaging to listen to for my ears; .i.e. "gets all of the notes perfect, but none of the music". Just returned another one of those in fact. I'm probably in the other camp, a musical 6SN7 dual triode tube preamp will always sit in front of my tube or SS amplifiers.

Thanks for the heads up, I won't expect any takers here on my ask, heading back over to the DIY forum, with tail tucked between legs. Hehehe

 

[Tedzap]

Have read this thread with great interest. I’m a newbie but wanted to put together a streaming 2 channel system for a new addition to the house. I ended up getting the c658 and c298, and am very pleased with the sound. Using Roon with Tidal for music.

It appears that some folks run the subwoofer off of the c298 instead of from the c658? Does this defeat the Dirac eq? I’m wondering if there are other setup things I have missed.

As the system is temporarily set up (addition is still months from completion) I’ve only done a tightly focused equalization. It made a nice difference.

My speakers are b&w matrix 805s with a b&w asw800 sub (also matrix vintage). I am using red river xlr interconnects and some rocket 33 cables.

 

[LarsV]

Oops wrong forum I guess. And, Exactly. I like a little bit of distortion design in the right places. That's the whole point, and what really good tubes can do. If done well it can offer nice second-order harmonics, which can be quite musical.

Coming from Class-A/AB solid state and Tube amps past 40+ years, some of the best measuring pure solid state amps in my own systems can tend to be very boring and un-engaging to listen to for my ears; .i.e. "gets all of the notes perfect, but none of the music". Just returned another one of those in fact. I'm probably in the other camp, a musical 6SN7 dual triode tube preamp will always sit in front of my tube or SS amplifiers.

Thanks for the heads up, I won't expect any takers here on my ask, heading back over to the DIY forum, with tail tucked between legs. Hehehe

For me goes the same. I have the XTZ Edge (Ice module) and when I added the Schiit Saga+ to it, it sounded more "musical" to my ears, and the soundstage got wider and deeper. Sold the Saga+ (kept the Edge) and got the Musical Fidelity M5si, which sounded a little better in every way. Now I am trying the C298 (through the pre amp of the M5si and straight connected to the Topping E30 dac) but although there are much more details, the sound to me is a little to digital. I am aware that I need to "burn in" the C298 much longer. Rest of my set up is Bluesound Node 2i, IFI power station, Silent Angel Bonn N8, Quad Z2 and of course good cables of various brands such as Audioquest, Supra Ply 3.4/S, Inakustik, etc.) Now I am thinking of getting a better DAC (Topping D70s) and streamer (Project Stream Box S2 Ultra) or an DAC/Streamer/preamp combo (Atoll ST 200 Signature). And of course I am playing with the thought of adding a tube pre amp again like I did with the Edge. Thinking of Musical Paradise MP 701. Too much options...... (oh and yes, I had to replace the C298 once, due to the well know auto shut off during playing. Replaced model had new firmware and no problems)

 

[decooney]

For me goes the same. I have the XTZ Edge (Ice module) and when I added the Schiit Saga+ to it, it sounded more "musical" to my ears, and the soundstage got wider and deeper. Sold the Saga+ (kept the Edge) and got the Musical Fidelity M5si, which sounded a little better in every way. Now I am trying the C298 (through the pre amp of the M5si and straight connected to the Topping E30 dac) but although there are much more details, the sound to me is a little to digital. I am aware that I need to "burn in" the C298 much longer. Rest of my set up is Bluesound Node 2i, IFI power station, Silent Angel Bonn N8, Quad Z2 and of course good cables of various brands such as Audioquest, Supra Ply 3.4/S, Inakustik, etc.) Now I am thinking of getting a better DAC (Topping D70s) and streamer (Project Stream Box S2 Ultra) or an DAC/Streamer/preamp combo (Atoll ST 200 Signature). And of course I am playing with the thought of adding a tube pre amp again like I did with the Edge. Thinking of Musical Paradise MP 701. Too much options...... (oh and yes, I had to replace the C298 once, due to the well know auto shut off during playing. Replaced model had new firmware and no problems)

@LarsV, very cool. As to your comment, re: "to me is a little too digital"... Fwiw, I was stuck there 2 years ago retrying and rotating all sorts of different preamps, amps back into the system - and DACs too. Focus then turned back to my DAC. Had a high-end ultra quiet and clean Benchmark DAC3 B DAC sitting here, 125db signal to noise ratio SNR and .00022% Total Harmonic Distortion (THD). Was nice, super duper clean sounding, amazing piece and super high build quality. Know of them from recording studios. Huge soundstage, large, forward some, and not my cup of tea. Was less musical sounding to my ears for my system, even paired with my best SS amps -or- tube preamps and tube mono block amps. What? Yes. For my digital side went back and started demoing Non-oversampling NOS R-2R Ladder DACs again w/wo tubes. Stopped here and have never looked back. Now it sounds very analog-like. No etch. No grain. Pure music. The vinyl rig sits now. I want to try this same front end setup with all tube, R2R Ladder DAC, tube preamp, with a nice Purify Class-D amp on the back end to blend the best of the two worlds to see what happens. Has potential. Similar approach to what ZOTL is doing with their amps, but I'm considering trying with full separates. Maybe restart with the source/DAC on your end, see if that helps. Can be a fun rediscovery too. Good Luck.

 

[ebslo]

Don't know how it amp's yet, but it's a great bongo drum. Seriously, does it bother anybody else that the C298 is a big resonant chamber? My other equipment chassis produce a dull thud when I tap them, but the C298 rings out.

 

[MJR]

Have read this thread with great interest. I’m a newbie but wanted to put together a streaming 2 channel system for a new addition to the house. I ended up getting the c658 and c298, and am very pleased with the sound. Using Roon with Tidal for music.

It appears that some folks run the subwoofer off of the c298 instead of from the c658? Does this defeat the Dirac eq? I’m wondering if there are other setup things I have missed.

As the system is temporarily set up (addition is still months from completion) I’ve only done a tightly focused equalization. It made a nice difference.

My speakers are b&w matrix 805s with a b&w asw800 sub (also matrix vintage). I am using red river xlr interconnects and some rocket 33 cables.

I am only using mine for 2-channel, so I can't say from experience, but should be very simple to set-up.
Dirac comes from the preamp, so should only work as long as Dirac can "see" your sub.
From the C658 manual:

• SUBW (SUBWOOFER) 1, 2 • Connect SUBW 1 and/or 2 to the low level input of corresponding powered subwoofer. • Low frequency information up to 80 Hz is sent to the connected subwoofer.

If you are connecting from the C298 amp using the sub's crossover manually, then you are going to be using the speaker wire inputs and would not be able to use Dirac for a separate sub AFAIK.

 

[Canth]

Don't know how it amp's yet, but it's a great bongo drum. Seriously, does it bother anybody else that the C298 is a big resonant chamber? My other equipment chassis produce a dull thud when I tap them, but the C298 rings out.

No problems for me. I do have an Oppp 105D on top of it, so there's no real room for a drum session.
However, I found the NAD to have a much more solid build than the appollon 1200AS that I had before. That had a generic case I could press and mould almost any way I wanted. Still sounded more than decent though!

 

[nothingman]

It’s pretty empty inside the chassis, but I don’t see how it matters at all. The chassis itself is rock solid and it’s a Class D amp. The lack of weight (and heat, etc) compared to a Class AB with a huge block of transformer copper isn’t a bug, it’s a feature.

 

[ebslo]

No problems for me. I do have an Oppp 105D on top of it, so there's no real room for a drum session.

However, I found the NAD to have a much more solid build than the appollon 1200AS that I had before. That had a generic case I could press and mould almost any way I wanted. Still sounded more than decent though!

Thanks, I'll find something to put on top. I wouldn't describe the build as solid though. The case is sturdy but the gain knob and bridge mode switch feel like a stiff breeze might blow them right off. Of course none of that matters if I can't stop it whining when the trigger is connected.

It’s pretty empty inside the chassis, but I don’t see how it matters at all. The chassis itself is rock solid and it’s a Class D amp. The lack of weight (and heat, etc) compared to a Class AB with a huge block of transformer copper isn’t a bug, it’s a feature.

Yeah, it's probably not a problem, I just feel funny about putting something with such strong resonance 18" from a speaker. I agree there's no reason it should be heavier.

 

[ebslo]

First acoustic noise measurements with this unit show 120Hz hum 10dB above the noise floor measured from 12 feet back coming directly from the C298 chassis. The tone is absent with the unit in standby, and present with the unit operational and everything but power disconnected.

 

[nothingman]

First acoustic noise measurements with this unit show 120Hz hum 10dB above the noise floor measured from 12 feet back coming directly from the C298 chassis. The tone is absent with the unit in standby, and present with the unit operational and everything but power disconnected.

What do you mean? Your unit is making an audible buzz just sitting there on the shelf, and you can hear it from 12 feet back? Something’s not right.

 

[MJR]

First acoustic noise measurements with this unit show 120Hz hum 10dB above the noise floor measured from 12 feet back coming directly from the C298 chassis. The tone is absent with the unit in standby, and present with the unit operational and everything but power disconnected.

Sounds like you have a defective unit. Return for a new one ASAP.
Mine is dead silent.

 

[ebslo]

What do you mean? Your unit is making an audible buzz just sitting there on the shelf, and you can hear it from 12 feet back? Something’s not right.

I can't hear it until I get prettty close due to other low frequency ambient noise (from nearby highway, etc.), but the REW RTA with UMIK-1 measurement mic puts it 10dB above the noise floor around 120Hz measured from 12 feet back.

 

[ebslo]

Sounds like you have a defective unit. Return for a new one ASAP.
Mine is dead silent.

Good to know, thanks. I thought it may be a design issue as it sounds like the kind of transformer hum that's very common in power supplies. In anything other than high-end audio equipment I wouldn't have given it a second thought.

 

[MJR]

Good to know, thanks. I thought it may be a design issue as it sounds like the kind of transformer hum that's very common in power supplies. In anything other than high-end audio equipment I wouldn't have given it a second thought.

The only other thing i can think of is some interaction with an interconnect, preamp or possibly a bad power supply.

 

[crbdrb]

Anyone know if this amp is rack mountable. Seems it should be but there is no mention of it on NADs site that I can find.