Rotel RB-1070 Amplifier Review

[Deleted member 48726]

Nice retro review, but even used price, I would not recommend it nowadays. Just not competitive anymore. Sure maybe 20 years ago it was, but not now IMO.

Which similar performance can be had to this but new?

 

[TonyJZX]

i would imagine stuff like emotiva and schitt have reasonably priced 100-150w stereo power amps out there?

 

[Tangband]

The main problem with these toroidal transformers amps is the hum pickup, which can be seen in the poor thd+n readings in every test. Is there a way to shield it?

I guess its not easy . One way is to put the toroidal transformer in another box far away from other electronics. A better way is to use a modern switched power supply . Read this from the audio company Benchmark, 2016.

Audio Myth - "Switching Power Supplies are Noisy"

This Myth Goes Something Like This: "Switching supplies are noisy." "Linear power supplies are best for audio." We disagree!

benchmarkmedia.com

 

[Marc v E]

I've always liked the look of rotel gear. That pop on noise would be a dealbreaker for me though. It might seems trivial, but I had an amp that did that and over time it made me dislike it more and more.

Ime there's something to great usabilty and smooth operation that makes me value devices more.

 

[pma]

You cant . One way is to put the toroidal transformer in another box far away from other electronics. A better way is to use a modern switched power supply . Read this from the audio company Benchmark, 2016.

Audio Myth - "Switching Power Supplies are Noisy"

This Myth Goes Something Like This: "Switching supplies are noisy." "Linear power supplies are best for audio." We disagree!

benchmarkmedia.com

It is more about PCB design than about toroidal transformer shielding. Shared 1cm of ground track from PCB supply bypass electrolytic capacitors (like 100uF) with the signal worsens mains residuals of 20dB. Been there, I know what I speak about.

Do not believe company papers. The only thing that is worth believing is own experience. Thus, you must go through the path.

 

[Deleted member 48726]

i would imagine stuff like emotiva and schitt have reasonably priced 100-150w stereo power amps out there?

Yeah it seems like you are right. Looks like nostalgia keeps the Rotel AB prices up.

 

[symphara]

Nice review! I share your feelings about Rotel amps. I recently got a RMB-1555 and it’s very, very quiet. No pop noise on startup either.

 

[Waxx]

You cant . One way is to put the toroidal transformer in another box far away from other electronics. A better way is to use a modern switched power supply . Read this from the audio company Benchmark, 2016.

Audio Myth - "Switching Power Supplies are Noisy"

This Myth Goes Something Like This: "Switching supplies are noisy." "Linear power supplies are best for audio." We disagree!

benchmarkmedia.com

It's like so often, in the early days they were very noisy as it was not mature technology yet. But today even mediocore cheap smps's are well shielded and the noise is not an issue anymore, and that already a few decades like that i think... The only place where i think a linear psu is better, is with high voltage circuits like in tube amps (but even there the smps is getting better).

But it's also not that linear psu's can be very low noise, it's just that it has to be done right. Here they could done it better, but also much worse.

 

[Gorgonzola]

When you can snag an Hypex NC252MP amp (with 12v trigger), for US$625 the Rotel for $500 looks lackluster for sure -- much higher noise and distortion.

For those that admit the sonic differences can exist between amplifiers, the distortion + noise spectrum for Rotel suggests that won't sound "harsh" but that it won't sound as detail or transparent as, say, a Hypex, and that it might sound a bit "grainy" -- granted, that will only be evident of one's associated equipment is very good quality.

 

[TonyJZX]

as shown in other threads here the Aiyima A07 can do 120w @ 8 ohm with the appropriate psu and I would guess the stats would tend to favor the Aiyima over the Rotel but these two wont be cross shopped and I think any comparison is HIGHLY academic...

its sort of like how a Tesla can do 300hp.... and so can a Chevy 350 V8... the Aiyima is a curio imo... a curio that admittedly even I'm interested in getting now but the Rotel I feel is like my old Parasound 1200 series.... I kinda cant get rid of it for some reason, not for want of no buyers.

 

[JayGilb]

The main problem with these toroidal transformers amps is the hum pickup, which can be seen in the poor thd+n readings in every test. Is there a way to shield it?

I have found that by rotating the toroidal transformer on certain electronics, it can help reduce the hum pickup.

 

[Deleted member 48726]

I have found that by rotating the toroidal transformer on certain electronics, it can help reduce the hum pickup.

How fast?

 

[TonyJZX]

you only have to rotate it until it faces mecca... alledgely binghampton, new york, home of the blue meters

 

[Thomas_A]

This is however very good compared to many amps tested on ASR:

 

[Thomas_A]

Hmm not very impressed. Compared with the topping pa5 with tpa 3251 chip inside ( same chip as my Aiyima a04 ) , the Topping pa5 outperform* the Rotel below clipping point. Lots of power with the Rotel though.

*In my experience, such differences is something that you can hear, to. The tpa3251 based amplifier will sound clearer.

View attachment 258707View attachment 258708

But will you hear the difference, blindly?

 

[DSJR]

To show how we were 'conditioned' against measurements, all the 'reference' amps which Martin Colloms tested and subjectively raved about (many/most were valved confections from the US with a couple from the UK) had sinad estimated in the 40's to 60's and his excuse was 'So much for measurements telling us how good a product sounds!' - or words to that effect! Most of the poorly reviewed amps, which all sounded thin toned and 'flat' in perspectives if you read the comments, had sinad estimated in the 80's and even approaching 90 back then and many of these latter amps had good current output as well into four ohm loads... We fell for it intertnationally and well, you know the rest.

 

[pma]

To show how we were 'conditioned' against measurements, all the 'reference' amps which Martin Colloms tested and subjectively raved about (many/most were valved confections from the US with a couple from the UK) had sinad estimated in the 40's to 60's and his excuse was 'So much for measurements telling us how good a product sounds!' - or words to that effect! Most of the poorly reviewed amps, which all sounded thin toned and 'flat' in perspectives if you read the comments, had sinad estimated in the 80's and even approaching 90 back then and many of these latter amps had good current output as well into four ohm loads... We fell for it intertnationally and well, you know the rest.

Hmm .. would you kindly be specific? How about this, for example

SoundStage! Measurements - Bryston 4B SST Stereo Amplifier (10/2004)

SoundStageNetwork.com | SoundStage.com - BHK Labs Measurements: Bryston 4B3 Stereo/Mono Amplifier

www.soundstagenetwork.com

Bryston 7B SST2 monoblock power amplifier Measurements

Sidebar 3: Measurements I examined the Bryston 7B SST2's measured behavior using mainly Stereophile's loaner sample of the top-of-the-line Audio Precision SYS2722 system (see the January 2008 "As We See It" and www.ap.com); for some tests, I also used my vintage Audio Precision System One Dual...

www.stereophile.com

 

[TonyJZX]

but this is the same argument we've always had in that we've owned poor measuring "shitboxes" like the NAD 3020 that subjective sound "good" but objectively measure bad.

 

[Klirren]

Maybe someday a Rotel class-D amplifier will find the way to Amir.

 

[Dmitri]

Brings me a lot of pleasure to read this review. I own an RMB 1095 5 channel amp and it has worked flawlessly for years. With that in mind, and though far from apples to apples comparison…I‘ve never had any significant pop on noise, and am wondering if that might be a defect in the current review amp.

Past subjective reviews…for what they may be worth…tend to describe the 1095…and I believe other Rotels, as having a slightly “veiled“ or “dark“ presentation. I doubt seriously I could tell one amp with similar power ratings from another, but my 1095…all 75 lbs. of it, certainly pulls at my old school strings.…huge power supply…capacitors like soda cans…gobs of output transistors and a basic feel of just plain solid mass and quality that I find tough to give up for the relatively featherweight class D offerings. The Rotel dominates the rack and still looks good doing it….and I like that!

Yeah, I know. Probably trying to make up for some personal insufficiency. But then again…it’s 15 plus years old and going strong…and the one piece of equipment I own that has never been subject to upgradeditis. I wouldn’t be surprised if it outlives me…and I plan on sticking around for awhile longer. ; )