Too much bass

Just got up after a good nights sleep and thought about the power tube issue. If the KT88's could cause this then that is likely my problem. The Rogues are the original 120's with the internal dip switches. I bought them several years ago as they were demo models. About 6-12 months ago the 88's were starting one by one to go. They are EH KT88's. The 4 remaining tubes that haven't gone yet are in one amp. And the other amp has a mismatch of 2 different types of tubes. And they are not EH tubes. JJ maybe or something like that. 2 of those and 2 of some other brand. If that could be it I guess it's time to stop cheaping out and get 2 quads of fresh tubes.

I have used this combo in 2 different rooms. I just recently moved to another house. My other house was my dream home that I built myself near a major Ski resort here in upstate NY. Well, good old NY state taxed me out of the house. Anyways, that room was 20'X 22'. This room now is much smaller. I think 11'X14'. the speakers are along the longer 14' wall because of doorway issues. I did have them along the shorter wall at first. In both rooms this has been an issue.
I have wondered from day one if they were the correct 8" drivers. I bought them here at AG last year and the seller said the 8" and midrange were replaced by Vandersteen.
The midrange is almost a clear or opaque color with what seems like standard silicone smeared on the foam surrounds. The 8" is a poly type cone. I tried to email Vandersteen to see if these were stock drivers but trying to get them to respond is impossible.
I have tried several positions from the rear wall. It does help some but the issue never goes away.
I kick myself for ever selling my Proac's. I just got board and had the itch to try other speakers. None I tried ever came close to them. They were the cheaper Studio 250's but the sure did sound good.
I am glas my audiophile OCD is all better now.
This is the first time I have been back to this site in many months.
I have tried both positions and I am currently running in ultralinear to get the most power thinking maybe the amps were clipping.

Viridian,

Thanks for the link and addtional info. Very interesting.

Thanks,

Burton

For what it's worth, I had a similar setup (Cary SLM-100 monos, ARC LS1, Von Schweikert VR4JR) and a similar problem. I solved 80% of the boomy bass problem through room adjustments (I have a dinky room and needed to absorbe bass waves) and Mapleshade brass footers.

Viridian,

Thanks for the info from Stereophile. Very interesting that the Richard's spec's are quite different than what Stereophile found.

Thanks,

Burton

I would say it is the room or mismatched amps. The vanderteeen 2 bass is a bit mushey I think. Play around I would sugest a 2wq though it would tighen the bass and give you more control over it. Also you can place it where it performs the best. I was never happy with my bass because of where the speakers had to be till I got a 2w.

What are your room dimensions, speaker placement, and listening position?

Sub-optimal placement could easily get you a 10X increase in bass power. Everything else is negligible compared to this.

I have a buddy that had the M120's(upgraded to the 150's) and Vandy 2Sigs and he never had any issues other than his room. He treated the room to tame too much bass. The Vandy's are 86dB @ 7 nomial ohms. Middle of the road load. I would call Rogue and question them about the issue.

Good Luck,

Burton

Scott, I was going to bring up the point Gunbei did, about amp/preamp mismatch, but you indicated that you didn't have this problem with several other speakers.

I suppose it could be the output tubes, as Gunbei suggests, but it seems unlikely they'd all go bad on both amps at the same time.

When I first read your thread title before popping in here I would have either said that your speakers were too close to the rear wall or you're sitting to far from them.

But after reading your post I think it has more to do with the amp and/or its synergy with your speakers and preamp. Does the Rogue have an ultra low input impedance? A bad set of tubes? Or maybe as Nsgarch suggests, that you try switching modes on the Magnum 120s or using different taps.

I had problem once with overwhelming bass after I had a component modified, so of course I attributed it to the equipment mod. However, it was easily corrected by pulling the speakers just a few inches further from the back wall.

How far is your listening position from a room boundary? I had a similar problem in my room if I was <4.5 feet from the rear wall. When I moved my chair out into the room the problem went away. Also how close to a room boundary are the speakers? One thing that helped me tune all of this in my system was to get a Radio Shack SPL meter and a Stereophile test CD with test tones. I had booms at 40-50 and 125 and suckouts at 70-80 and 160Hz.

My $0.02

Aaron

If the M 120's are in Triode mode, try switching them to Ultra-Linear mode. Also (I assume you are, but....) use the 8 ohm tap for the 2c's. Other than that, your amps should have plenty of power.

The other possible issue might be speaker wire. Not the kind, let's not get into that, but the length. IMO, if they're over 8 ft. long, then the (tube) amps might be having trouble controlling (damping) the woofers. Also, as you may know, Vandersteen recommends bi-wiring these speakers for tightest bass.

Are you sure it's not the room? You have all solid equipment, and your amp should be able to handle those speakers I would guess.