Celestion Ditton 44 Speakers - Any good?

[Tony L]

I had 66s for a while and they were not very good at all. No deep bass and no treble impact.

Wow, how on earth did you manage that?! I’d not have thought it possible not to get bass impact from the 66! They are designed for wall proximity though. Very good chance the tweeter was broken if you had no treble, they are fragile and cross quite high from the mid-dome so a fault could be missed.

 

[chartz]

No the tweeters were fine, crossovers restored and all. I was disappointed because of everything I had read on them. They were against a brick wall. Still I couldn’t hear anything below 60 Hz or so.
I have a drum set in my music room I compare my hi-fi to.
My Arcam Ones were much, much better to tell the truth.
They are now at my son's flat and they are more at ease than they were in my large room – and certainly better than their TV sound system!

 

[ToTo Man]

No the tweeters were fine, crossovers restored and all. I was disappointed because of everything I had read on them. They were against a brick wall. Still I couldn’t hear anything below 60 Hz or so.
I have a drum set in my music room I compare my hi-fi to.
My Arcam Ones were much, much better to tell the truth.
They are now at my son's flat and they are more at ease than they were in my large room – and certainly better than their TV sound system!

Not all HF2000 units are performing to spec after 40+ yrs (trust me, I've measured around 25 units! ).

The original 66 grille absorbs a significant amount of HF energy and does so in a non-linear way (it reduces HF output by as much as -2.5dB at certain frequencies). I prefer to listen to mine with 10mm or 15mm acoustic foam fitted instead of the original grilles. Running them naked is great too but produces slightly too much HF compared to something like a JR149, but it's very smooth and airy and not at all fatiguing. I guess if you're used to hot top end you might find the 66 too polite with the grille on, but if you remove the grille or replace it with acoustically transparent foam I think it's pretty much on the money.

FWIW the smoothest balance MF/HF output is achieved when the listening position is on-axis with MF, if this is not possible then the speaker should be tilted backward to compensate. If listening position is higher than HF axis, you get a broad cancellation between 5kHz-10kHz due to the wide frequency overlap between the two drivers and the relatively large distance between them (this becomes less of an issue the further away you sit from the speakers).

Regarding bass, I have no lack of bass from any of the 3 pairs of 66 I've owned. It's not a "bass monster" like some people say, but it easily gets down to 40Hz in a typical UK listening room without any trouble. In a bigger room I'd expect it to roll off higher, probably around 50Hz as per the anechoic FR.

EDIT - @chartz, I'll upload a graph later today showing the difference in treble response when the grille is on vs off.

 

[ToTo Man]

Sorry for the delay in posting these measurements, but better late than never!

Last time I measured the effect of the Ditton 66 grilles was in 2019. It was my other pair of 66, and the measurement was taken when the speakers were on 200mm high plinths and at a distance of 2 metres from my listening seat.

I repeated the measurement on my current pair of 66 today. These 66 are sitting directly on the floor but are tilted backwards using 30mm rubber feet placed under the front edge of the cabinets, and are at a longer distance of 2.65 metres from my listening seat.

I have included both the 2019 and 2021 measurements in the graph. As you can see, the grill caused stronger attenuation of the HF response in the 2019 measurements. It still absorbs an audible amount of HF energy in the 2021 measurement (approx -1dB), but evidently not as much as the 2019 measurement. Therefore, if you find the 66 too dull in the top end, removing the grille probably won't increase the treble by the amount you need.

 

[richardg]

I had a pair of 66s for about a month. Great bass but honky mids was the problem, so they went.

 

[ToTo Man]

I had a pair of 66s for about a month. Great bass but honky mids was the problem, so they went.

They do have too much midrange relative to treble. The MF500/MD500's raw response itself isn't linear (it's shelved up towards the low mids and shelved down towards the presence region), and AFAICT the crossover makes no attempt to correct for this. However, if working to spec the MF500/MD500 driver is low distortion, and a simple notch EQ filter to lower the 500Hz-2kHz by -2 or -3dB works wonders to smooth out the response. Of course not everybody has the facility to EQ.

If the midrange is 'honky' in the sense that there is audible resonance or harmonic distortion then this would point to a fault with the driver. Apparently the glue securing the dome can fail over time and cause buzzing, and this process can be expedited by driving the speakers too hard especially if the MF capacitor has gone out of spec and is passing too low a frequency to the mid.

 

[richardg]

They do have too much midrange relative to treble. The MF500/MD500's raw response itself isn't linear (it's shelved up towards the low mids and shelved down towards the presence region), and AFAICT the crossover makes no attempt to correct for this. However, if working to spec the MF500/MD500 driver is low distortion, and a simple notch EQ filter to lower the 500Hz-2kHz by 2-3dB works wonders to smooth out the response. Of course not everybody has the facility to EQ.

If the midrange is 'honky' in the sense that there is audible resonance or harmonic distortion then this would point to a fault with the driver. Apparently the glue securing the dome can fail over time and cause buzzing, and this process can be expedited by driving the speakers too hard especially if the MF capacitor has gone out of spec and is passing too low a frequency to the mid.

not buzzing...just too much mid for me.