Formula for good speaker size for room ?

[Fivetide]

Is there a good formula for speaker size in relation to the room’s size?
I want to build some speakers that fit the room my hi-fi is in.
At the moment I have a choice of speakers :

RTL TDL2’s mk1’s
B&W 602’s

These are hooked upto a
AC Azur 650 A
AC Azur DacMAgi
Sony SACD.

I find the B&W’s are to powerful, hard to explain the room somehow makes them sound muddy at medium volume, but this get less as I lower the volume, it’s as if the sound bouncing back at the speakers , I can’t explain it I’m no audiophile, I just like what I hear.
The rooms about 20 ft by 16 ft, and I listen between the 16ft walls. So sat in my chair I’m probably 12 feet from the speakers.
Anyone recommend a speaker size for those dimensions I could easily build?
I’d like just a all-round listening speaker, I don’t mind spending money on good parts and the case I can make at my friends joinery shop.

[Fivetide]

Sorry I forgot to mention the TDL's , I had a Pair 20 years ago and loved them, I bought this pair , because I wanted to see if I could create another set with better parts.. they are tired, old and scratched .. bit like me , but somebody has to love them.. I will be taking them apart soon

[sreten]

Hi,

Move the B&W's away from the back wall and side wall, until they sound right.

Its not rocket science, and done properly bass extension will sound better.

They must be on correct height stands, to work well.

Moving your chair away from the back wall will smooth bass.

rgds, sreten.

[Fivetide]

Originally Posted by sreten

Hi,

Move the B&W's away from the back wall and side wall, until they sound right.

They must be on correct height stands, to work well.

Moving your chair away from the back wall will smooth bass.

rgds, sreten.

This is the problem, space I dont really have that much room around the speakers, one of the reasons I was thinking of going to a smaller speakers.
Smaller speaker with higher specs I think may help the room accustics?
After reading other threads its seems the amp you are hooking up to makes a difference in speaker part choice.

The AC 650a :-

Power Output: 75 Watts (into 8 Ohms)

THD (unweighted): <0.002% @ 1kHz, 80% of rated power
<0.03% 20Hz - 20kHz, 80% of rated power
<0.02% 20Hz - 20kHz @ 10W

Frequency Response: 5Hz - 50kHz (-1dB)

Signal to Noise Ratio (No weighting): >92dB

Input Impedance: 47kohms

Power amp damping factor: >100

Max. Power Consumption: 600W

[sreten]

Hi,

I basically completely disagree. Your room is big for the speakers.
Try lining the ports with 1/4" open cell foam, length x 3xdiameter
to tighten up bass, And typically make rear wall distance ~ half
stand height and typically side wall distance ~ double, or more.

rgds, sreten.

Your other options are to go with a large rear wall distance, greater
than effective stand height. This gives the best lower bass boost.

[Fivetide]

Originally Posted by sreten

Hi,

I basically completely disagree. Your room is big for the speakers.
Try lining the ports with 1/4" open cell foam, length x 3xdiameter
to tighten up bass, And typically make rear wall distance ~ half
stand height and typically side wall distance ~ double, or more.

rgds, sreten.

Thanks I'll try that, I'll move the furniture around I will try it length ways as the longer walls have a door in the middle on both sides .. I'll set it up and take a picture..

[AllenB]

There is a lot to be said for putting them (and yourself) in the right location. Upper bass and midrange will benefit from this. Bass is different, subs can help, but I'm speaking here in the interest of placement not bass extension. Small changes can be worth trying. Subtle, but not...

[Fivetide]

Once I have made the space I will retry my RTL Transmissions because they do suffer from cramped surroundings.. but like I said they need upgrades they have had "Bad previous owners"

[Fivetide]

Originally Posted by sreten

Hi,

Try lining the ports with 1/4" open cell foam, length x 3xdiameter
to tighten up bass,

Sorry to sound dum but does that mean stuffing them from the front or opening the Case and lining around them ?

[sreten]

Originally Posted by Fivetide

Sorry to sound dum but does that mean stuffing them from the front or opening the Case and lining around them ?

Hi,

A piece of foam port length x 3xdia can be folded into a tube
and inserted into the port, where it will be self supporting,
this will detune the port, tightening the bass somewhat.

rgds, sreten.