Rogue 88 problems


I bought an used Rogue 88(not magnum). I met couple of problems, hope somebody could help me out.
1. The fan gives rather big noise. My listening room is small (13X12), and it's really annoying. The seller told me the amp is about a year old. Is it about time to change the fan?
2. I hear sparks from the speaker in the first 20 mins when I turn 88 on. What could be the cause of this?
3. This one is not really a problem. When I switch from UL to triode, the volume of sound dosen't change. I am expecting the sound to go down, because the output is half of UL.

Thanks in advance.
pren
Hello? does anyone still have a Rogue 88? I’ve just got one which was ‘tuned’ and I need help from someone to get the original values of the capacitors because mine were changes to different values :(
Thank you!
Sounds great. Thanks for the feedback. I have seen other posts on this site that rave about the M120s.
Without question the 120's will provide those qualities and more over the 88. I had the Magnum 88, and now the Magnum M120's. Just leaps and bounds above the 88. I also use the Magnum 99 preamp. I wasn't thrilled with the 99 matched up with the 88. I knew I spent a lot of money. I new I was running tubes. I knew I was running in triode. I just wasn't wowed. I was also going to sell my 99. After I hooked up the M120's, the 99 sings. I love the combination. I traded my 88 and $900 for the demo pair of 120's. No looking back or any regrets.
Thanks for the feedback folks. I am looking for more "presence" in the low mids, more bass slam and for a bit more separation. In your opinions will the 120s do this compared to the 88 ? I have Meadowlark Shearwater Hot Rods with the 99 pre amp, CAL 10 CD player, DH labs Q-10 cables. Thanks
Th 120 have double the power of the 88. 120 Watts vs 60 Watts I belive. Did you listen in Ultralinear or Triode. Triode on the 88 is 30 Watts, I used them on a pair of 92dB speakers with great succes, then got 120 and Know the 150.
Last amp I will need.
Everything !! First of all, I am using a pair of Proac Studio 250 speakers. They aren't the most efficient in the world. 89db I believe. The M120's have gobs of power compared to the 88. Every note seems presented effortlessly as compared to the 88. The 88 ( after looking back at the sound as compared to the 120's) seemed strained and maybe a little congested compared to the 120's. I felt happy with the 88 for a little while. Maybey 7 or 8 months. But then I grew tired of the presentation. I am not the most electricaly technical person here so I can't explain the theory of operation but, there are 4 KT88 output tubes per channel as opposed to 2 with the 88. That has to count for something right? Not only that but, the 120's are great heat source for a cold room :-)
I felt that I couldn't go wrong. I traded my Magnum 88 and $900 for the pair of 120's and I haven't been happier.
Scottht,
What differences did you note with the M120 vs the 88 ?
I am considering upgrading to the M120s. Thanks Len
A Bob Crump DIY is all you need to get this thing sounding great.
Any more spent and its a waste.

no more that 5% of your budget should be spent on cables.
I use an Audio Magic Illusion power cord on the 88 with great results. The sound is more expansive, for lack of a better word.
on a side note
has anyone had any good/bad experiences with different power cords and the 88?
Well. I have to add this. I had my Magnum 88 for 9 months like I said earlier. I tried everything to make it sound the way I expected it to. Cables, tubes, power cords.
Well I just got my M-120 Magnums. There is an amazing difference between these 2 amps. Finaly my system sounds the way I thought it should after spending many thousands of dollars. Unbelievable, It is like I replaced the whole system. If you ever get tired of the 88, give the M-120's a try. You won't be disappointed.
Pren,
I have the 88 for about 2 yrs now. When I first bought it (new) the fan was audible from 8-10 feet away. I sent it back to Rogue who swapped it out and now I cannot hear it.
I have found Mark O'Brien to be very responsive to customer inquiries so you might contact him directly at Rogue. Len
Why make comments thaat are not true. I ran a Rogue 88 for over a year with the fAN DISCONECTED.
Thank you all guys. Scottht and Precbsed, you are right about the power cord. I'd found the original dosen't connect securely, but didn't realize that gives the arc. I changed the power cord, no problem now. Also, Scottht, besides the characteristic of sound, did you observe volume change when you shift from triode to UL?
The performance, reliability and responsiveness of Rogue Audio is well documented in this and other forums across the internet. Let the reputation they've earned speak for them.

The internet is a big place and bad news travels fast. If their were reliability issues , you would have heard of them by now.

I've never had reliability issues with my Rogue stuff and I've always had emails answered promptly when I asked questions. Many companies do not treat their customer like this and we have to give fair praise to the few that do.

Email Rogue.
My information comes from not once heard complains about performance(not meaning a sound) of Rogue amps and preamps. I've never looked inside these units but I can assume that they're using high bias circuitry that makes a tube life short so freequent retubing may be neccessary.

I happen to see that in listening room with magnum M120 having a same described hiss and noise.

I guess that some models are built good and some of them aren't.

I'd perform overall look onto the solder joints but after one year it realy shouldn't be an issue in any electronic device.
Scottht makes a good point. Cleaning the tube sockets did not eliminate the arcing right away but it did stop sometime thereafter so that may have had nothing to do with the problem. After reading Scottht's post however it did occur to me that at the time of the arcing I was using a fairly high-end power cord that was somewhat inflexible and didn't seem to connect as securely as the stock cord. I believe it may have been after going back to stock power cord that I no longer noticed the arcing.
Well I can tell you that I spent about 1 month trying to get rid of the arc issue. I tried everything from switching out tubes to moving my components around. I finaly took the approach of cleaning up the mess of power wires in the rear. I made an effort to isolate every power cable and make sure they were all quite a distance from each other. Problem gone. I was giving up but it worked. The sound is better now also. I have since ordered a naw power cord.
I have no problem with my fan. I can only hear it if I get right down next to it.
I have had mine for 9 months and for the first time last night I put it in UL mode. Definate difference in sound. A little lean for my taste but it is there. Maybe because I have been listening it triode mode for 9 months that now I prefer that sound. Sometimes if you haven't spent time with the sound and you switch back and fourth you might not catch the difference right away. Give it some time in one mode or the other.
Next, don't listen to this guy about reliability. He appears to be one of these wannabe experts that needs to spread his opinion around. You have a very good amp, and there is not another builder around that is as nice a guy and as helpful as Mark at Rogue.
Pren,
Regarding Marakanetz's post, do yourself a favor and try the simple procedures I recommended before you despair. Oxidation and debris build-up have nothing to do with design or build quality. If that doesn't work I would contact Mark O'Brian at Rogue. Mark and his staff are extremely helpful and very responsive. FYI I have used my 88 Magnum and a Rogue 66 Magnum preamp almost daily for over three years without any issues other than the aforementioned which were easily rectified.
Marakanetz-where does your information come from regarding poor reliability or performance issues regarding Rogue?
You are the first person I have ever encountered making a statement to this effect.

What Rogue component have you had you had a problem with?

If you know of some who have had problems please direct them to this thread.
Anyone have a complaint regarding Rogue??
FWIW my old 99 always perfomed perfectly and does so to this day for the new owner.It must be 5 years old by now.
Pren,

You're in the bad situation because

a) you can't get away without fan(due to high-biased tubes in amplifier)
b) fan is always noisy especially DC motor ones.
c) Rogue is known for its "innovative" designs that either have reliability or performance issues biting a consumer thereafter or even soon after the purchase is made.

Solutions:

a) Assuming that there is a DC motor try to use AC motor fan that is substantially less noisy. It's easy to reconnect the leads before the rectifying bridge if this is the case.

b) Don't use expencive speakers or make sure that the warranty of your speakers covers the poor amps' perfomance(s).
I had what sounded like arcing on start up as well with my 88 Magnum. I cleaned all the tube sockets and it eventually stopped happening. To quiet the noisy fan I simply removed the cover and thoroughly dusted the fan and its housing with a soft make-up brush. It worked. I have only used the ultralinear mode so I can't help with your last question.