Could the output of my 2M Blue be clipping my Dino Ml2 phono stage?

[m10]

I suppose my question is there in a nutshell, but of course there's a story behind it.

I've been mostly really pleased with my Technics/2M Blue/Dino 2 combo since getting back into vinyl and (what seems sometimes) like saving HMV from the liquidators single-handedly. That said, on a couple of albums I noticed a little distortion on climaxes. One good example was Stacey Kent's The Changing Lights (Pure Pleasure) which, I observed, seemed to have been cut at a very high level - volume setting 8 or 10dB down on a 'normal' LP. That said, the effect was slight and the LP gave such pleasure (even compared to the already wonderful CD) that I put it to the back of my mind.

So -- I have a splurge on Amazon and buy myself the box-set of The Complete Tony Bennett-Bill Evans recordings. Wonderful music, but the sound is hideous - cut high like the Stacey Kent but almost every Bennett climax (and this is Tony Bennett so there's a lot of them) with significant, sometimes hideous distortion. The bundled Amazon MP3s showing the vinyl a clean pair of heels in the SQ stakes - surely the wrong way round!

So, I was ready to send the LPs back and swap them for the CD set (at a saving of £84) when I wondered if there was a system-related cause of the problem. Mind working overtime, and with a little googling and limited knowledge I thought - what if these 'loud' LPs are clipping the phono stage? I conceived an experiment - plug straight into the MM stage on my Yamaha amp.

I had used the Yammie phono stage before, as a 'try-out' before the upgrade to the Dino. Comparisons found it flat (dynamically) compared to the Dino back at the time, and I'd never (of course) looked back. However, connections made and levels matched by ear (with a volume setting 12dB higher than before) and, while there are still some 'issues' on climaxes, I find the LPs suddenly listenable with distortions much improved.

So... (and congratulations if you've read this whole meandering post) I think I need to check the settings on The Dino. But, what of my original question? Have I hit the nail on the head here?

I've been thinking about an upgrade, and my mostly positive feelings about the 2M Blue have led me to think of the 2M Black - with a properly matched phono stage (perhaps) or is it time to go the MC route. What's the experience here? Are there better cartridges in the MC world to trace these type of 'difficult' records?

Thanks in advance for the advice and wisdom. I'm a bit of a noob when it comes to vinyl (on the technicalities at least).

[Arkless Electronics]

It should be fine so long as you are using one of the two lowest gain settings (48 or 52dB), which are the correct ones for a MM cartridge.

[Andrei]

Malcolm
Friends. TT owners. If there is an intersection in the Venn Diagram you could ask to play your LPs on a friend's system to see if the problem is reproduced. If not then you can eliminate the LP from the potential diagnosis.

[Arkless Electronics]

So long as MM gain settings are being used there is no possibility of the phono stage clipping. It's probably mistracking distortion from a few very "hot" recordings....

[lurcher]

So long as MM gain settings are being used there is no possibility of the phono stage clipping. It's probably mistracking distortion from a few very "hot" recordings....

I agree its unlikely, however the output might be causing the input to your amplifier to clip though.

The 2M is spec's at 5.5mv at 1khz 5cm/sec, +10dB is possible off the record, thats 15mv, the lowest gain on the dino is 48dB, so thats 3.7v out. I could imagine that clipping a line level input on the preamp side, especially if there is a gain stage before the volume control.

[Barry]

The Yamaho RX - V1067 has a line-level sensitivity of 200mV. If we assume an overload figure of 30dB, then this input will suffer overload at 6.3V.

Taking your figures:


The 2M is spec's at 5.5mv at 1khz 5cm/sec, +10dB is possible off the record, thats 15mv, the lowest gain on the dino is 48dB, so thats 3.7v out. I could imagine that clipping a line level input on the preamp side, especially if there is a gain stage before the volume control.

the input is unlikely to be overloaded. The same applies if we use the correct figures of 17.4mV and 4.37V.

[lurcher]

The Yamaho RX - V1067 has a line-level sensitivity of 200mV. If we assume an overload figure of 30dB, then this input will suffer overload at 6.3V.

Taking your figures:

the input is unlikely to be overloaded. The same applies if we use the correct figures of 17.4mV and 4.37V.

OK, it was just a suggestion. But I do find it amusing that you seem to be criticising my rough figures, while basing your much more precise ones, on a pulled out of "the air" overload figure.

[Firebottle]

Ahh, the benefit of valve phono stages - loads of headroom :)

[Barry]

OK, it was just a suggestion. But I do find it amusing that you seem to be criticising my rough figures, while basing your much more precise ones, on a pulled out of "the air" overload figure.

My "pulled out of the air" overload figures are quite typical for line-level inputs; in fact 40dB is more usual, but I thought I would 'err' on the side of caution. Unfortuately Yamaha do not quote the overload figure pertinent to their RX-V1067.

My apologies - no criticism was intended.

[Arkless Electronics]

Ahh, the benefit of valve phono stages - loads of headroom :)

Most of which will be lost by passive EQ :D Still plenty left with valves though ;) I have a prototype valve hybrid phono stage with passive EQ here that's WIP myself!
It seems the Dino uses passive EQ though which does mean much more chance of clipping than I first thought. As long as it's set to 48dB though it should be fine.
Mistracking is still my number 1 suspect for the OP's problem.

[They call me Ron]

I have been running a 2M Bronze through a Dino mk1 for several months now. I think it's a really good phono stage. But I nearly sent it back to the seller so alarming was the distortion I initially heard. But I contacted Trichord, who told me the phone stage was overloading the line input of my Cyrus amp. They adjusted the Dino for free (reduced its output via MM) and even upgraded the output chip to the latest version for a modest fee. The service was excellent and it has been perfect since. Try talking with Trichord (I forget the chap's name) as your issue may be similar.

[lurcher]

My "pulled out of the air" overload figures are quite typical for line-level inputs; in fact 40dB is more usual

40dB on 200mv is 56.5v peak to peak. that is not a trivial requirement.

[m10]

Thanks all for the thoughts and advice. All the settings on the Dino check out. I may get in touch with Trichord, but I'm happy to accept the aberration is down to the LPs in question (the Tony Bennett set is going back to Amazon today).