RB-1090 injured... :(

[PewterTA]

Ohhh today is a rough day...

Last night I went to turn off my Rotel RB-1090 amp and when I pressed the button.... well the light stayed on... which I thought was odd. SO my thinking was, I missed pushing in the button all the way and it didn't turn off, so I bent over again and pushed the power button. However, when I pushed it, it went to the "ON" position... Thinking this was a little bit odd I pushed it a third time and no luck. The amp would NOT turn off!

Due to the lateness of the evening and the fact that work comes very early in the morning, I reached back and pulled my brand new power cable (Blacksand Audio Violet Z1 MKII - and yes this cable is making a very nice difference with this amp) and waited till today to look at the amp.

Unfortunately (which I think Rotel should reconsider), I bought this second hand off of Audiogon about 2 1/2 years ago, so no warranty for me. So with that thought, I looked around on line (and with talking to Tyler at Rotel) about getting a service manual and opening the thing up and trying to fix/see if the power button got damaged some how.

Now I take IMPECABLE care of my equipment and since I got it, I've only added one minor scratch to it, otherwise, I think there were about 3 almost unseeable scratches when I got it... so this thing has not been abused. So I was thinking the switch might have gone bad...but had no clue.

I started opening up the amp trying to get the face plate off and was very successful at doing this however one set of wires that ran into the front heatsink was not quite long enough. So in my attempts to free the piece I needed, I broke one set of wires. :evil:

Knowing that I would have to get it back on, I decided to try to follow the wires deeper into the amp and realized there was a board right on the bottom left (looking at the front of the amp) that they ran to. Well it looked easy to get out so I started undoing more of the amp and well I found this...



I'm guessing this is most likely the problem and I'm guessing not the switch... After seeing this and knowing I definitely will be without the amp for a week or so... it's already killing me! Luckily I had both a 1080 and 2 channels on the 1095 that I could use so I'm not completely without music and the HT... however after sitting here listening to music while I type this and do a few other things... the 1090 is definitely in a another league compared to the 1080.

The 1080 is very similar, but doesn't have the smoothness and power of the 1090. Low end has definitely suffered the most. But also the realism of instruments is not quite there with the 1080 (course that could be due to non-use for almost 2 1/2 years.... :/

So knowing I would be without the amp for a week or two.... I decided to take the rest of the amp apart. I'm thinking that I might replace some of the wiring with some better quality wire, most of the internal wiring is 14 to 18guage and looks like possibly 12 going to the binding posts...

The only thing I know for certain is I'm going to put some Deoxit Gold on all the connection points to help (might as well as everything is this accessible) :B

Anyways, I figured everyone would like to see the thing disassembled! :E

This is what's left of the chasis, I'm going to take the back off (4 or 5 screws on the bottom) and then decide what I'm going to do with the power connections and speaker connection cables.


Right channel heatsink.


Left channel heatsink.


Caps.


Faceplate.

[Industrial]

Poor thing...

[PewterTA]

Got the service manual and it's the Thermistor on the Surge Absorber board.

I think I had a surge here in the last week or two because my FiOS router died on me right after I was watching TV and the cable box rebooted itself. So I'm thinking something happened in the house.

Now I just have to find the Thermistor (or order it from Rotel) and I think it'll be back in business!

[hurin]

A new thermistor and a soldering iron should do the trick, much cheaper than sending it for repairs.

On a different topic. I'm not trying to insult you, but your talk about expensive power cables and the 1090 making a world of difference over the 1080 sounds awfully familiar. I'm sure if you owned a set of Dynaudio Consequence, the 1090 would make a huge difference. But I'm guessing you don't have speakers quite that big.

Long story short, you got a problem with acoustics, I'm guessing big speakers vs. small room. And you're trying to fix it with powerful amps and gimmicks like expensive cables.

Putting some bass traps on the walls and replacing that polyester carpet with a thick wool carpet really would make a world of difference.

[PewterTA]

I guess that's my fault on not saying things correctly.

I'm using the cables on my 1080 as well. It's not the cables that are making the differences between the two amps... it's the amps themselves that are different. The low end extension on the 1090 is the biggest thing you can notice, it doesn't seem to get the deep low sounds that the 1090 does. The mid range is very much the same on both amps. The high end is just a slight bit better on the 1090...it's tough to explain, but horns have a difference on the 1090 were they seem to come out at you more. It's sort of tough to explain, but there is a difference. It's not like I'm saying the 1080 is a POS and barely can drive my speakers at all... not in a long shot. After almost 3 years, I'm just used to the 1090.

The cables weren't all that expensive (compared to what's out there)...but they are making a difference. The differences I've heard (both on the 1090 and it seems very similar on the 1080) are LESS bass, but much tighter sounding with more detail. I really hear the strings vibrate off the neck board more than I've ever heard before and the plucking of strings are quicker and done with more power to it (as in it sounds more powerful vs not really hearing it). The mid range has changed over to a smoother sound. It almost sounds like female vocals (and even male) are an octive higher (I know not really, but that's the best way I can explain it) and clearer with more detail yet still has a more musical, smoother, and "silkier" sound to it. The highs are not as bright, and tinny but have more detail and cymbals ring and sound more realistic along with a longer noticeable decay. These are all things I've never heard before on my system. And the only thing that's changed is those cables on my Pre, Amps, and CDP. So I don't know what else I didn't do that would've changed the sound like this.

Now everything I've noticed I say seems to be the same with switching over to the 1080, so again I'm not saying the 1080 is weak or the quality is like using a cheap POS. I'm saying it's close to the 1090, but it's not the 1090.

And for the record, I've ALWAYS been one that did NOT think cables did anything. So the fact that I'm hearing a difference with using these power cables (and I've had 3 other people verify the changes without me saying one word or them knowing things had changed. So I can't complain about that... at least it's not just me hearing things and no one else is.

My room is decent with everything in it for sound treatment but I would like bass traps and to do a ton of other work to it, but in the long run it probably won't happen (bass traps might). My room is 15ft x 30... so I think the room fits well the B&W DM604s3s that I'm using. Well that is until I build the Ardents.

[PewterTA]

Well I just thought I'd let people know that I got the 1090 fixed. I replaced the part that was broken and was having an issue with the right channel shorting out. I couldn't figure out what the problem was so I went back an forth with Rotel and was going to send it to them, but at the cost, I found VintageAudioPGH.com and the owner Tom. I took the amp to him to have him look at it and he found two parts that failed on the right channel and replaced all my fuses. The cost was just under the price for me to ship the amp to one of Rotel's service centers. So you can't beat that!

The amp is in great working condition now!!!

I also took the time to WBT silver solder all ring terminals that were just crimped on all the connections. As well as use the Deoxit Gold on all connections I didn't solder.

OMG, it's almost a night and day difference!!! I'm temped to put together a manual on how to do this for anyone that wants to REALLY change the sound of their system. Every aspect of the sound seems like it's a brand new amp!!!

I initially did this on my 1080 that I fixed and was absolutely blown away by the change. It was SOOOO good in fact that I contemplated not getting the 1090 repaired. The mid and high range of the 1080 rivaled the 1090 in EVERY single way. It was just like comparing McIntosh or Classe to Rotel. It got "that" much better!!!

Now I'm not saying that my 1090 now competes with McIntosh or Classe, I'm saying that it has a similarly sounding type of an improvement as replacing it with one of those.

Anyone that has a 900 or 10xx series amp should do these "mods" as it makes a VERY noticeable improvement. The sound is still the Rotel sound, it just has much more life and clarity and smoothness across the sound. It's almost an effortless sound!!!

It's soo good, that I took apart my 1090, 1080, 1095 and 1098 and did it to all connections to all of the units and it has blown me a a couple of others away. Enough to have been asked if I was using some other type of equipment in my laundry room that they couldn't see.

Anyone interested in trying this out, I'll give people the full breakdown on any of the above listed equipment to take it apart and put it back together.

This is how Rotel SHOULD have sold these amps/pre... because it would've really pushed Rotel above any status they would have in the quality of their gear.

As always, anyone that is in the Pittsburgh, PA area, if wanting, I will gladly do this mod for a couple bucks (or a beer or two), would only take me an hour or two to take it apart, solder everything and re-assemble.

WKHanna... Yours is next as I "mod" your 1090 and we see how much better it sounds!!!! I'll let you borrow my 1080 while I do it if we can't get it done during one of my stops over. hee hee.

[PiDD]

Wow great write-up.

I also have the 1090, 1080, 1095 and 1098... so take the cover off and solder all the crimp connections and de-oxit all the connectors?

[PewterTA]

Yep that's all I did... made a very nice difference!

[PiDD]

Great! I ordered the WBT silver solder. I just need a rainy/snowy weekend!

Thanks for posting your info.

[PewterTA]

No problem, if you get stuck on anything just let me know and I'll answer any questions you might have on disassembling and reassembling.

Let me know what you think on the differences (if any)!

[gp4Jesus]

Two of you have...

...1098s

Is that the RSP 1098? Or a Rotel amp?

Either way, I see PE sells the solder. Where to buy Deoxit? I'd like to do my recently acquired RB-98, my Hafler XL-280s, and, if you think its worth it, my RSP-1068.

Thnx tony

[wkhanna]

Dan's re-work / upgrade is applicable to any audio electronics.
Deoxit at PE