Vinyl trouble Part 3: Boomy sound

Here is Part 3 of my never-ending series of vinyl trouble: boomy sound. I also recommend Parts 1 and 2: "Excessive brightness" and "Distorted cymbals" - they are a great read.

Lately I have noticed an increasingly boomy (=bassy) sound when playing LP records. Tone controls are set to flat (=neutral, zero, 12'o'clock position). I have not made any changes to my listening room; no new furniture has been moved, added or removed.
I have not moved my speakers. They are still standing where they have always been. The rack is the same. The position of my turntable on the rack is the same. Everything is still the same. But now, even records that in the past needed a gentle bass boost, seem to have too much bass. I don't experience the same phenomenon with CDs, so I don't think the problem is my listening room.
This problem of excessive bass only started occurring in the past two or three months.

What can have happened?
Is it possible that my cartridge has suffered some kind of "damage" after riding at a higher than average tracking force for a year?

Once I tried setting the tracking force to the highest allowable value, 1.75 grams, but the sound became too boomy, so I put it back to 1.65 grams, which balanced the sound again, but now lately I am hearing too much bass, even though the tracking force is the same.

Any suggestions?



Edited by Analog Kid - 23 Nov 2009 at 8:07pm

I completely forgot about this. Will upload some pictures soon.

Is it not possible that the cause of the boomy sound (excessive bass)
is a result of the rack and turntable being poorly isolated, causing
bass vibrations from the speakers reaching the record/needle interface
through the floor and rack, thereby disturbing the stylus motion?

It seems like the most probable theory, because I don't have
this problem of excessive bass when listening to cassettes and CDs.






Edited by Analog Kid - 29 Mar 2010 at 12:30am

Graham Slee wrote: @AK: there seems to be something wrong in your system, doesn't there? First it's excessively bright, then distorted, now boomy. Whatever item it is, it seems to have a big fault. We would be happy to check out if it's our preamp. Would the other makers do also?

I highly doubt my problems have anything to with my phono stage.
The Reflex has been a big improvement for me, over the built-in
phono stage of my Technics amplifier.

The brightness I hear is most likely caused by my Audio-Technica AT150MLX cartridge.
Looking at the included frequency graph, a +2.5 db rise is noticed between 15 kHz
and 20 kHz. Even my dealer who installed the cartridge admitted that Audio-Technica
cartridges tend to sound bright. Besides, the excessive brightness is mostly on
hard rock and metal records, a genre that is naturally mastered bright. I also
have many records that don't sound bright.

The sound of my vinyl playback was not always boomy, so it can't have anything
to do with the Reflex. My turntable, Pro-Ject RPM4, is a low-end 400 euro model.
The turntable base and platter are only 2.5 cm (1 inch) thick each and are made of
cheapish MDF (Medium Density Fibre). Back in February 2008, a few months before
I purchased my Reflex, I had the original rubber turntable feet replaced with special
spikes that are a sandwich construction of wood and rubber rings. Also got a new
rack around the same time, which has the rack columns filled with sand, to reduce
vibrations, apparently to no avail.

I tried to move my speakers further back towards the wall, which helped a tiny bit.

Maybe you can provide me with further suggestions based on the pictures of my
system and listening room.


Edited by Analog Kid - 29 Mar 2010 at 6:21pm

Hi AK, to start with I would get the turntable back in its original as possible state.