TX-RZ70 | Onkyo
The Onkyo TX-RZ70 11.2 Channel AV Receiver delivers remarkably pure sound, stellar visuals and the latest technologies to power the heart of your home…
-
Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
Onkyo Tx-RZ70
- Thread starter Five24287
- Start date
soerenssen
Addicted to Fun and Learning
- Joined
- Jul 25, 2023
- Messages
- 562
- Likes
- 132
AV just measured the RZ70:
- stereo 264W 4 Ohm 1kHz Sinus
- 5.1 159W 6 Ohm 1kHz Sinus
- 7.1 88W 6 Ohm 1kHz Sinus
These are just slightly worse numbers than the A1H measurements, at least in stereo and 5.1.
- stereo 264W 4 Ohm 1kHz Sinus
- 5.1 159W 6 Ohm 1kHz Sinus
- 7.1 88W 6 Ohm 1kHz Sinus
These are just slightly worse numbers than the A1H measurements, at least in stereo and 5.1.
Last edited:
Why no measurements at 8 ohms?
Robert-Hifi
Active Member
If I remember correctly their reason was most speakers nowadays are true 4 or 6 ohm load.
Full measurements are:
2 channels:
205 Watt (35,1V) / 6 Ohm / 1 kHz Sinus
264 Watt (32,5V) / 4 Ohm / 1 kHz Sinus
5 channels:
159 Watt (30,9V) / 6 Ohm / 1 kHz Sinus
147 Watt (24,3V) / 4 Ohm / 1 kHz Sinus
7 channels:
88 Watt (23V) / 6 Ohm / 1 kHz Sinus
If this is true, I'd like AVR manufacturers to get w/the program and report these numbers as well!
AV? do you have a link?
techsamurai
Addicted to Fun and Learning
- Joined
- May 26, 2022
- Messages
- 816
- Likes
- 290
All the new AVRs seem to have a high drop from 5 to 7 channels. But that's really not that important for anyone who has a sub.
I ran full range bi-amped fronts (7ch) for 13+ years so I was doubling my LR consumption and pushing low-end frequencies and it never complained or felt compressed.
The moment I got a sub even with my lower crossovers, it barely heats up. It's those 2 octaves at the bottom that seem to demand the most power.
In fact, given the fact that people will run at least 1 sub with these, I'd rather see smaller transformers capable of higher 3 channel wattage (3x150 watts or 4x120), more capacitance (60k-100k), smaller toroidals, copper chassis for better isolation and other things to improve sound. Put the money where it matters most.
If someone needs more power, they can always get a small external amp for a few channels but they can't increase the quality of the main unit although these do seem really well built but it's sad to see the omission of a toroidal even if it cost $100 more.
I ran full range bi-amped fronts (7ch) for 13+ years so I was doubling my LR consumption and pushing low-end frequencies and it never complained or felt compressed.
The moment I got a sub even with my lower crossovers, it barely heats up. It's those 2 octaves at the bottom that seem to demand the most power.
In fact, given the fact that people will run at least 1 sub with these, I'd rather see smaller transformers capable of higher 3 channel wattage (3x150 watts or 4x120), more capacitance (60k-100k), smaller toroidals, copper chassis for better isolation and other things to improve sound. Put the money where it matters most.
If someone needs more power, they can always get a small external amp for a few channels but they can't increase the quality of the main unit although these do seem really well built but it's sad to see the omission of a toroidal even if it cost $100 more.
The big weakness with most AVR's is that they have a single power supply - shared across everything - and that means once you start to drive more channels, you start to run out of current... and the power drops off.....
If your main load is the lower frequencies (often the case with many speakers where the impedance is lower in the bass) - and you cut it off at the knees with a crossover - transfering that load to the powered sub - you are left with more oomph for the rest!
Occasionally you see a usually very expensive AVR with enough grunt to really drive many channels to the max - but it is unusual.
soerenssen
Addicted to Fun and Learning
- Joined
- Jul 25, 2023
- Messages
- 562
- Likes
- 132
Onkyo TX-RZ70 (audiovision 11-2023)
audiovision.de
Sounds logical.
On that, I would caution that there are many internet hearsay/audio myths and the toroidal story is one of them, though in general, all else being equal, toroidal power transformers tend to do more good than bad in AVR/amps applications. You will certainly find someone who specializes in manufacturing or marketing toroids that tell people toroids are the best choice for audios, that's marketing 101.
You just can't generalize too much, as EI core, R core and other designs also have advantages that may make them the preferred choice in some applications. Many cost no object kind of amps also use non Toroids, such as Luxman, McIntosh (some models). Back to AVR, Denon has been using their custom designed E-I core for their flagships in recent years, including the $6,500 A1H, but they also use toroids in their older models. There are also many low cost amps (I have a couple) that uses toroids, it is not always a case of "$100 more". The fact is, some toroids are better, some are not, it depends on how they are designed and made, and the specifics of the applications such as the layout, and yes cost could, and often be a factor too.
Robert-Hifi
Active Member
AV is the German magazine Audiovision.
Soerenssen links to the PDF review of the Onkyo TX-RZ70 which you have to pay for.
Personally, I have bought the paper magazine version of Audiovision 11/2023.
In this issue the Onkyo TX-RZ70 is reviewed.
techsamurai
Addicted to Fun and Learning
- Joined
- May 26, 2022
- Messages
- 816
- Likes
- 290
We've had that conversation a few times and I agree mostly because I grew up with the Sansui 8080 and that didn't use a toroidal.
But Sansui did use dual toroidals in their best receiver the G33000. It's a tough one because you have the 8080/9090 and then you have the G33000.
Speaking of the AH1, the 5803-06 had toroidals so in Denon's case they are probably saving money. It's a bit cheesy to buy a $6,500 70lb top-of-the-line AVR with an EI when Monolith has dual toroidals for 1/3rd-1/4th the price and weighs 93lbs. Also how is the AH1 isolating the AVR from external interference? I know Marantz uses copper chassis on the 8000 series and PM series and Yamaha does similar stuff on the power supply so what does Denon do?
We should be calling them out for that.
We have had many more conversations too, but I've got the impression that you tend to believe what you wanted to believe in general based on things you read/heard prior, and I wish you could be more open minded to consider the objective side of things, so I haven't given up completely yet
. In the case of the A1H Gene said (in his review, more like a preview) Denon uses E-I likely because of the layout that would make it difficult to fit a toroid that provides the same VA rating. I have quite a few power amps, the cheapest ones (not including my class D amps) happen to have toroids. My vintage Marantz power amp has EI. I can't imagine Denon picked an E-I for the A1H, A110 and 8500 just to save a few dollars, but it is of course possible. Keep in mind, a custom designed E-I with meticulous shielding to control leakage flux, and tightly wound, wouldn't be cheap, could potentially cost more than an equivalent toroid.Here's one example of why toroid is not used, and not because of cost:
It's another $6,000 Denon flagship amp, a 50 W, 8 ohm, 100 W, 4 ohm, 2 channel stereo analog only integrated amp:
Hard to tell it is E-I, R-core, but it's unlikely a toroid, externally it obvious look like an ovoid lol..
Last edited:
techsamurai
Addicted to Fun and Learning
- Joined
- May 26, 2022
- Messages
- 816
- Likes
- 290
That's funny - I have no clue what it is. They chiseled the top plastic cover to fit the cables. It's clearly fairly modern given its heatsink (black - is it painted or an alloy) and I see lots of copper on the sides and on the screws. The capacitors are in some sort of enclosure too - interesting.Gene thought Denon uses E-I likely because of the layout that would make it difficult to fit a toroid that provides the same VA rating. I have quite a few power amps, the cheapest ones (not including my class D amps) happen to have toroids. My vintage Marantz power amp has EI. I can't imagine Denon picked an E-I for the A1H, A110 and 8500 just to save a few dollars, but it is of course possible.
Here's one example of why toroid is not used, and not because of cost:
It's another $6,000 Denon flagship amp, a 50 W, 8 ohm, 100 W, 4 ohm, 2 channel stereo analog only integrated amp:
Hard to tell it is E-I, R-core, but it's unlikely a toroid, externally it obvious look like an ovoid lol..
I do like the clean symmetrical design of the RZ70 (and the siblings from Integra and Pioneer) which I think Yamaha is also using in their high-end stereo receivers like the 3200 and 2200 and Denon in the AH1. That seems to be the new norm.
My question is what happens if you plug in speakers with 3.2 Ohms DC resistance and drive them at reasonable power.TX-RZ70 | Onkyo
The Onkyo TX-RZ70 11.2 Channel AV Receiver delivers remarkably pure sound, stellar visuals and the latest technologies to power the heart of your home…onkyousa.com
I seem to recall Amir giving up on the Onkyo TX-RZ50 when it instantly went into protection mode when a 4 ohm load was applied.
Has anything changed with new ownership, or can we expect the TX-RZ70 to choke on "real" 4 Ohm loads?
ban25
Major Contributor
- Joined
- Nov 5, 2022
- Messages
- 1,214
- Likes
- 1,257
Feel free to look at my signature for the answer to your question.
I would say just knowing the dc resistance is not enough,. To answer your question, I would like to know the impedance and phase angle vs frequency curve. Also, it is more useful to look at the voltage and current requirements than power, though if the amp is really powerful then it will usually do well in both.
Edit: The RZ50
Last edited:
Agreed, but it's not regulated, so it is unlikely that they would do it on their own. In practice, it is not that bad either because if the spec says 100 W 8 ohms, the amp will do more for 4 ohms for speaker loads and for real world use, at least in most cases. For use with truly 4 ohm nominal speakers that can handle a lot of current, then it will be a good idea to use external amps rated adequately for the load.
I didn't say it shut down, I said it went into protection mode, meaning the power output is drastically reduced.
Onkyo tech support recently recommended against using 4 Ohm speakers with their AV receivers.
As to your comment, the DC resistance is the minimum possible impedance, obviously. The speaker manufacturer no longer quotes nominal AC impedance but I expect it's 4 to 6 ohms given their previous products. So you're talking a fairly low impedance load. Their recent conversion to Purifi midbass drivers has led to a very low nominal impedance, so they just quote the DC resistance.
On the other hand if you've heard Purifi drivers, you'll understand.
My issue is that previous Onkyo products have had serious issues driving a 4 ohm load, likely due to overly conservative protection circuitry.
Their MBAs and attorneys are obviously more concerned about warranty claims than performance.
I suspect that if you disabled the protection circuitry an Onkyo TX-RZ50 could easily drive 4 Ohm speakers to reference levels. I think the nanny mode was probably overdone, but it is what it is.
Based on reviews I would never buy a TX-RZ50. But I was hoping that perhaps the industry trend toward 4 Ohm speakers and perhaps the new owners have altered things.
But I want confirmation from the community before considering buying this receiver over a processor and some serious high current amplifiers.
Right now the Monoprice processor and their low impedance amplifiers seem a better bet.
Onkyo tech support recently recommended against using 4 Ohm speakers with their AV receivers.
As to your comment, the DC resistance is the minimum possible impedance, obviously. The speaker manufacturer no longer quotes nominal AC impedance but I expect it's 4 to 6 ohms given their previous products. So you're talking a fairly low impedance load. Their recent conversion to Purifi midbass drivers has led to a very low nominal impedance, so they just quote the DC resistance.
On the other hand if you've heard Purifi drivers, you'll understand.
My issue is that previous Onkyo products have had serious issues driving a 4 ohm load, likely due to overly conservative protection circuitry.
Their MBAs and attorneys are obviously more concerned about warranty claims than performance.
I suspect that if you disabled the protection circuitry an Onkyo TX-RZ50 could easily drive 4 Ohm speakers to reference levels. I think the nanny mode was probably overdone, but it is what it is.
Based on reviews I would never buy a TX-RZ50. But I was hoping that perhaps the industry trend toward 4 Ohm speakers and perhaps the new owners have altered things.
But I want confirmation from the community before considering buying this receiver over a processor and some serious high current amplifiers.
Right now the Monoprice processor and their low impedance amplifiers seem a better bet.
