JBL SA750: Dirac, Class G, Roon Ready, Phono, and REAL KNOBS

[watchnerd]

Well that sounds and looks interesting...

https://www.whathifi.com/us/news/jbl-sa750-is-a-modern-retro-class-g-amplifier-with-streaming

But I don't even know what Class G is.

But it says it's Roon Ready and has a lot of other inputs, including phono:

"There’s MQA and Roon Ready support on that front, and on the physical side of connectivity is a range of analogue and digital inputs – two opticals and coaxials apiece, six pairs of analog RCAs, and single MC/MM phono, 3.5mm and USB sockets. Completing the spec sheet are 3.5mm and RCA preamp headphones outputs, plus Dirac Live room calibration. "

And Dirac!

For $3000.

Might be a better buy than the NAD M33.

Although I don't know why they named it after a Jelco tonearm....

 

[watchnerd]

Press release:

https://news.harman.com/releases/releases-20210105

 

[Neddy]

Pretty, but still a bit of a stretch compared to the (my) SA-660
Probably better specs, tho....

 

[levimax]

Multiple knobs and a retro aesthetic but no tone controls seems like a miss.

 

[watchnerd]

Multiple knobs and a retro aesthetic but no tone controls seems like a miss.

No VUs.

 

[Depoxy]

Multiple knobs and a retro aesthetic but no tone controls seems like a miss.

Isn't that what Dirac is for? Dialing in a custom house curve seems like the modern version of tone controls.

 

[watchnerd]

Isn't that what Dirac is for? Dialing in a custom house curve seems like the modern version of tone controls.

There are uses for tone controls other than altering a house curve.

Maybe a particular album you like is marred by a bright top end and you just want to temporarily take the edge off, not permanently adjust your room EQ.

Who wants to re-run Dirac just to do that for a one-off?

 

[levimax]

Isn't that what Dirac is for? Dialing in a custom house curve seems like the modern version of tone controls.

I use DSP for "room correction" and tone controls to adjust for either a "flawed" recording or for very low listening levels.

 

[ElNino]

It's a shame this isn't a 2.1 device with the Dirac bass control module.

 

[MakeMineVinyl]

Didn't we already have a discussion about class G in another thread on JBL?

BTW, if JBL designed this thing in its entirety in their Northridge, CA facility, I'll eat my computer monitor.

 

[watchnerd]

Didn't we already have a discussion about class G in another thread on JBL?

BTW, if JBL designed this thing in its entirety in their Northridge, CA facility, I'll eat my computer monitor.

Northridge, Korea, maybe.

 

[mhardy6647]

https://www.audiosciencereview.com/...50-integrated-amplifier-for-us-3000-00.19170/

 

[Steve Dallas]

There are uses for tone controls other than altering a house curve.

Maybe a particular album you like is marred by a bright top end and you just want to temporarily take the edge off, not permanently adjust your room EQ.

Who wants to re-run Dirac just to do that for a one-off?

If the device has more than 1 slot, you can save different EQ profiles to different slots and switch between them, and you can do it from the same project file. No need to re-run the measurements.

I have "Brighter," "Neutral," "Warmer" presets in my media room and the same with and without desk in my office. The Windows Dirac Live Processor has 8 slots.

 

[watchnerd]

If the device has more than 1 slot, you can save different EQ profiles to different slots and switch between them, and you can do it from the same project file. No need to re-run the measurements.

I have "Brighter," "Neutral," "Warmer" presets in my media room and the same with and without desk in my office. The Windows Dirac Live Processor has 8 slots.

I usually don't know what the necessary EQ I want is ahead of time.

A tilt control works perfectly for this.

It's trivial to implement -- my studio monitors have it built in.

Even the Puffin phono DSP has a tilt control with, if I recall, like 8 levels.

A tilt control lets me tune it by ear.

 

[levimax]

If the device has more than 1 slot, you can save different EQ profiles to different slots and switch between them, and you can do it from the same project file. No need to re-run the measurements.

I have "Brighter," "Neutral," "Warmer" presets in my media room and the same with and without desk in my office. The Windows Dirac Live Processor has 8 slots.

Of all the crazy things in the "Hi-Fi" world one of the craziest is the dropping of tone controls from high end gear and calling it "better". Yes you can more or less accomplish the same thing switching DSP software "profiles" but that is far from the very intuitive turning of a knob while listening. For me the main use of tone controls is for low level listening.... either a loudness button or turning up the bass makes big positive difference. I guess the fact that good tone controls are relatively expensive to implement and don't really work well in the digital domain is going to prevent any tone control come back which is a shame. Tone controls can add a lot more to a system than an extra 10 or 20 dB of SINAD in most cases.

 

[watchnerd]

don't really work well in the digital domain.

I'm not sure what you mean by this.

I think they work fine in the digital domain.

Here is the tilt control graph for the Parks Audio Puffin, all implemented in digital domain.

 

[levimax]

I'm not sure what you mean by this.

I think they work fine in the digital domain.

Here is the tilt control graph for the Parks Audio Puffin, all implemented in digital domain.

If you have DSP room correction that reduces headroom by lets say 10 dB and then try to add another 10 dB of digital tone control bass boost you can run out of head room in a hurry and need some analog gain at which point it kind of gets expensive and complicated

 

[watchnerd]

If you have DSP room correction that reduces headroom by lets say 10 dB and then try to add another 10 dB of digital tone control bass boost you can run out of head room in a hurry and need some analog gain at which point it kind of gets expensive and complicated

10 dB is a heck of a tone control.

I don't know any that are that exteme.

 

[levimax]

10 dB is a heck of a tone control.

I don't know any that are that exteme.

I believe that a lot of tone controls in the past had +/- 20 dB of range... Which is why turning the controls all the way up or down sounded so extreme. Besides fashion I am not sure why tone controls are not more popular but expensive and dodgy analog pots and digital headroom issues dont help.

 

[watchnerd]

I believe that a lot of tone controls in the past had +/- 20 dB of range... Which is why turning the controls all the way up or down sounded so extreme. Besides fashion I am not sure why tone controls are not more popular but expensive and dodgy analog pots and digital headroom issues dont help.

If correct, that's pretty nuts.

But I suspect that +/- 20dB is not correct.

In comparison, a modern analog tone control in the Luxman L-509X:

Tone control Max. amount of change BASS : ±8 dB at 100 Hz
TREBLE : ±8 dB at 10 kHz
Loudness control 100 Hz : +7 dB 10 kHz : +5 dB