RSL iA255.1 Class D integrated amplifier discussion

[SMc]

Key items - 90 Hz bypass switch, toggle between 3 inputs, true sub / pre out, good tone controls & power and sound quality. A full review here would be great. From what I've read, most reviewers say this has more real world power than the Fosi amps, even though they may be rated at higher power outputs. A very interesting product from an American company.

How much of that "real world power" is attributable to volume knob position due to choice of taper?

 

[gafortiby]

How much of that "real world power" is attributable to volume knob position due to choice of taper?

in my case, none -- I turned the FOSI V3 (32V power supply) knob to 100% max. Then I was able to match the decibels with my RSL iA255.1 by turning the RSL to 60% of volume knob. I could not actually turn the RSL knob beyond ~80% because it would have blown out my speakers and my eardrums.

Yes the taper does make a difference, the RSL pushes move decibels earlier in the knob. But it also has a much higher max decibel.

 

[Opus_003]

I did a side by side comparison of FOSI V3 and RSL iA255.1. Sample of things I tried:

• John Williams conducting Jurassic Park.
• Happy by Pharrell Williams
• Come Together by The Beatles

The only conclusion I reached was, my ears are not audiophile enough.

Seriously though, I have no idea how the ASR community judges sound quality in human subject terms. I could use the Cheapaudioman method and say things like "the soundstage and instrument separation is fantastic" but I don't have the prerequisite number of social media followers to make such claims myself. (I actually do like watching Cheapaudioman.) I can tell when an MP3 is overly compressed or if there is some interference hiss, but between these two amps I can't tell any difference in sound quality. My guess is that the RSL iA255.1 sounds as good as other good MA12070 amps, and the FOSI V3 sounds as good as other good TPA3255 amps.

One thing I did notice is that there is audible static (not high pitch just regular background noise) only the iA255.1 when a source is attached and the volume is turned to the max. However I think this is actually an amplification of my audio source's noise, because there is zero noise at max volume if the RCA input cables are disconnected.

Thank you! No worries. I appreciate the information. I like Cheapaudioman too. I like having both ASR and CAM's input on a product. If they both like it, I'm inclined to try it out, though I didn't like the SMSL SU-1 DAC and they both liked it. Nor the V3. Mmm. Maybe I need to rethink my position, lol.

 

[MStan]

I just bought one of these today (RSL is local to me). I am impressed. I intended it for a garage system but garage only system my a$$! This thing sounds seriously good.

Don’t judge this amp until you feed it a pristine signal. Turn off the digital volume control from the cheap streamer box, bypass the sub filter and tone controls and feed it a lossless source and you’ll hear how good this thing is. I am using a WiiM box streaming lossless on its digital out to a Benchmark Dac and Infinity P363 monitors. Sounds transparent to me as a competent amp should. No fatigue after half a day listening. I can find no fault with the sound. And no heat whatsoever - stone cold. What a bargain these $100 class D amos are!

 

[OC350z]

I just bought one of these today (RSL is local to me). I am impressed. I intended it for a garage system but garage only system my a$$! This thing sounds seriously good.

Don’t judge this amp until you feed it a pristine signal. Turn off the digital volume control from the cheap streamer box, bypass the sub filter and tone controls and feed it a lossless source and you’ll hear how good this thing is. I am using a WiiM box streaming lossless on its digital out to a Benchmark Dac and Infinity P363 monitors. Sounds transparent to me as a competent amp should. No fatigue after half a day listening. I can find no fault with the sound. And no heat whatsoever - stone cold. What a bargain these $100 class D amos are!

Just ordered one myself, what exactly do you mean bypass the sub filter and tone controls?

 

[Gaden Phoenix]

When is the next USA sale? Want to get me one of this with some speakers? Not sure USA holidays sales. Is the next big one in October? Their 3 months break till Jan season right? Turkey day, Halloween and Christmas or something I guess.

 

[ampguy]

I like the toggle switches for input and filter bypass, but too limited for me. While the sub out is nice, it's still a single input unit for my uses, as I would not use that built-in DAC. Also, no balanced inputs, no tone defeat. Not sure this is really better than the $90 SMSL A100 (measured on this site) with same chip and built-in power supply, and normal RCA jack for sub. That unit does about 18W @ 8 ohms, and ~40W at 4 ohms but may have a smaller power supply, though it is built in, which is nice for many desk applications. Also, the SMSL has a remote, for those that want one.

 

[TonyJZX]

i think really everything at this price level is kind of a compromise on some level... its just whether you can live with the downsides.

To me this does everything quite well but its for someone who wants that 'bag of deplorables' (such as it is)

eg. the wonky digital in, no remote etc.

A like amp is the Arylic B50... I would rather it do less but.. better like a V3.

I too would love to see a Fosi V3 with 80w+ and XLR... you can lose everything else.

There's a lot of people who love those $100 boxes that have everything in them like BT and phono etc. etc. - that's probably not a type person here but it is a customer out there.

 

[Reydepancakes]

I'm curious how this reviews and may purchase.

Is the USB DAC perfect? No but 16 bit is fine. Leaves a nice path to upgradeability with a new DAC and eventually, because it has some basic features without going overboard, can be used as a side stereo system in the dining room or something.

Big draw for me is RSL and that it has the sub out so I can get a rythmik L12 to pair with my HiVI 3.1a I'm building. Big con for me is I simply don't know if the 55w 4ohm rating is enough (granted I'll be basically listening near field..).

 

[Gaden Phoenix]

Is this a good 2.1 Amplifier? Comparable to the Fosi v3?

 

[yepeekai]

I'm having problem with my current setup. I initially thought it was the speakers but now I'm really thinking it is the DAC part of this amp... I recently bought this amp with CG3Ms and Speedwoofer 10.

My ears were hurting even at low volume. I plugged the ia255.1 via USB to the computer. I tried lowering stuff in the equalizer (in foobar) and lowering the treble on the amp, the sound wasn't as good but it was still hurting... I never had this problem with music before. (for example I have Schiit Fulla with HD598 using USB)

Today, I plugged the amp with the line in to the cheap realtek output of the computer and the problem is, I think, mostly gone. I'll wait a couple of days to be sure.

I will do some other tries but if someone experience something similar, I think it would be a good place to start...

The computer might be the problem (conversion from 44.1 to 48) but for what I read, this shouldn't be noticeable.

FYI, I am nowhere near being an audiophile, so take all this with a grain of salt.

 

[yepeekai]

Ok... I am back at not being sure what's going on... I listened to a video from the cheapaudioman "7 Free Hifi Hacks that will change your Life" and some stuff cause me to question a couple of things. I tried the tone thing and when I slowly increase the frequency of the tone, sound loudness shift from left to right and right to left very often... So I suspect there is a problem with my room acoustics. I improved things by turning the speakers outward. I have a weird very low loudness at 125Hz. I tried the decibel X app and without being precise, gave an idea and I am planning on running an analysis with REW.

So, at this point I don't want to blame any equipment I have.

 

[gafortiby]

Ok... I am back at not being sure what's going on... I listened to a video from the cheapaudioman "7 Free Hifi Hacks that will change your Life" and some stuff cause me to question a couple of things. I tried the tone thing and when I slowly increase the frequency of the tone, sound loudness shift from left to right and right to left very often... So I suspect there is a problem with my room acoustics. I improved things by turning the speakers outward. I have a weird very low loudness at 125Hz. I tried the decibel X app and without being precise, gave an idea and I am planning on running an analysis with REW.

So, at this point I don't want to blame any equipment I have.

You could have a ground loop issue if the USB (laptop?) is grounded differently.

 

[Don927]

How much of that "real world power" is attributable to volume knob position due to choice of taper?

Unknown on that. What I have read is that the RSL seems to drive speakers better than most of the usual Fosi And Aiyima amps.

 

[Reydepancakes]

Purchased.

First impressions are good. Powers hivi 3.1a and Polk lsi 25 to non listenable levels. Clean sounds. Build quality is about what I'd expect from a $100 China amp. It's small, few plastic bits, center detent isn't perfectly centered. All very minor initial qualms with otherwise great first impressions.

 

[Leethompson]

So, everyone can tell me. This amp( rsl ia255) is good or not with 110usd. And it's chipset is good? Thank so much.

 

[yepeekai]

One bad thing I can say about this amp is the USB input. I was getting noise when a usb cable is plugged in even if I select the "line" input. So in my case I won't ever plug a usb input in that amp. That was a feature I was looking for so I am a little less enthusiast that I was. I bought a SU-1 from SMSL to feed the line input and I am happy. Considering the Fosi V3 will get the volume adjusted preamp (for subwoofer) soon, making that choice now, I would probably go with the SU-1 and Fosi V3 instead of this amp. I will probably buy the Fosi V3 anyway to compare. The SU-1 definitely improved things (not only noise free, but the sound is better than the included DAC in the ia255.1). I think I was expecting too much from this amp. It is good, but not perfect (for me).

 

[JeffB1961]

it has a 2 year warranty .
did you contact RSL about it to see if they can offer advice to correct it or if they offer to fix it under warranty ?

https://rslspeakers.com/rogersound-labs-ia255-1-integrated-amplifier/

they have a 800# in the top right corner of their site .

 

[Reydepancakes]

One bad thing I can say about this amp is the USB input. I was getting noise when a usb cable is plugged in even if I select the "line" input. So in my case I won't ever plug a usb input in that amp. That was a feature I was looking for so I am a little less enthusiast that I was. I bought a SU-1 from SMSL to feed the line input and I am happy. Considering the Fosi V3 will get the volume adjusted preamp (for subwoofer) soon, making that choice now, I would probably go with the SU-1 and Fosi V3 instead of this amp. I will probably buy the Fosi V3 anyway to compare. The SU-1 definitely improved things (not only noise free, but the sound is better than the included DAC in the ia255.1). I think I was expecting too much from this amp. It is good, but not perfect (for me).

I get noise for maybe 3 seconds as it starts with the USB c input.

1 month update. It works fine and I think probably a great unit at its price point from my limited knowledge.

 

[ZINHAR]

Got mine last week. It's been a decent upgrade over my old TPA3116 which couldn't even get loud enough for nearfields. There is a slight hiss, though not nearly as bad as what you'd get on powered speakers. Overall, a great little amp for the price. The RSL iA255.1 is essentially an improved version of the SMSL A12.

Also worth mentioning, I saw a plastic 3.5mm to RCA cable included in the box on The Frugal Audiophile's channel, but my unit actually came with a really nice braided cable.