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In Reply to: RE: Quicksilver mc step up posted by sk on July 31, 2024 at 16:19:04
I've had them all. In fact I have all the versions. The very early ones had great highs but was a little rolled in the bass. The next to the last version was the best but I'm having a hard time picking between the new one and the last one. I also have a Cotter which is in the same league. His new one is all silver wired. Most of the current ones available are terrible. I tried a lundahl and sent it back
Follow Ups:
Maybe it's time to try an active head amp instead of a SUT (so you can get optimum cart loading - instead of just what the SUT gives you)??
Or switch to optical cart and then none of this matters.
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Why would I try anything if I am already achieving great sound. Active head amps I don't like. The transformers are set to fixed impedances. I only use cartridges that don't require loading to compensate for peaked highs. Also the cotter has jumpers that impedances can be set.loading down a cartridge almost always sounds worse except if it is of poor design
Not quite sure what you mean by that AJ ... as a SUT delivers a loading to the cart which is plugged into it.
And as for " loading down a cartridge almost always sounds worse " - I totes agree with you.
Loading " UP " is what I am talking about. When I had a Benz LP, if I had been using a 1:15 SUT ... it would've provided a load of 47k / 15^2 = 209R.
With a coil impedance of 33 ohms - that load is less than the minimum 10x; I actually found it needed 3300 ohms (ie. 100x coil impedance) to sound its best.
You need a head amp - where gain is independent of loading - to be able to do this! :-o
The transformers I use are well matched with internal impedance of coil. Never heard a head amp that I liked except one. However they are much better than jfet to increase voltage of moving coils. Klimo made a head amp called the Argo. I liked that but it broke a lot.
Many/most head amps are solid state. Among solid state gain devices, it is common to use a JFET in this application. So it's likely that if you used a solid state head amp that you liked, you experienced JFET amplification that was at least acceptable. Not that there's anything wrong with that.
Counterpoint used to make an all-tube head amp (model SA-2, I think), even including tube rectification. It was very good but had a reputation for becoming noisy. I owned one for a while, and I did like it. I don't know of any other examples using tubes only. Some high gain phono stages use tubes in conjunction with transistors, usually a JFET. Manley Steelhead is one example.
I just stick to a Hana ml. Tube phono preamp and a cotter stepup
The Hana ML is just about the perfect cart to use with a SUT into a tube MM phono stage.
A 1:10 SUT delivers 470 ohms to the Hana - which, with a 7 ohm coil, represents 70x coil impedance!
I know. That's why I always use Hana. I have a unami blue on order for a Kuzma Stabi r with Stogi ref 313 vta. Sweet...
Well, any cartridge with an internal impedance of 40 or less ohms would be suitable for use with a 1:10 SUT, assuming the phono stage presents the standard 47K ohm resistor as input impedance. That leaves a wide choice of LOMC cartridges, not just the Hana candidates. This is provided your MM phono stage can supply the requisite additional gain to properly drive your linestage/amplifier/speaker. And lots of folks break the "10X rule" with aplomb.
Not so.When I had a Benz LP (coil impedance 33 ohms), its output meant that a 1:15 SUT would be ideal. This would deliver a load of 209 ohms - which, given Benz's loading recommendation of 470 to 47k ... would be totally unsuitable.
Using a ss head amp into an MM phono stage - with the head amp having infinite loading options (using plug-in 'load plugs') - I found 3300R gave the best sound (higher and the bass lost its firmness; lower and the soundstage closed in). IE. 100x coil impedance.
Edits: 08/07/24 08/07/24
It depends on the phono preamp input sensitivity as well as the topology of the phono EQ/amplifier circuit as to what pre stage gain is required.
The Benz LP has a specified output of 0.35mV so 1:10 would have been fine with the Benz LP for most MM phono stages unless you are using one with a lower input sensitivity greater than 5mV to get a higher input overload margin such as with passive EQ designs. The difference is only about 4dB from a phono stage with a 3mV input sensitivity which is common for many outboard and onboard phono stages of the past; Musical Fidelity notably being one example with their X-LP and other derivatives.
Regards Anthony
"Beauty is Truth, Truth Beauty.." Keats
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Have Fun and Enjoy the Music
"Still Working the Problem"
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Sorry, that's simply nonsense.
You made the claim that the cartridge would have needed a 1:15 step up in reply to Lew's post quoting 1:10 as being generally fine for cartridges up to 40 ohms DCR.
You can't talk about the step up gain/ratio for loading without considering the input sensitivity of the main phono amplifier i.e gain. The norm is for a 3mV to 5mV input sensitivity and Benz clearly anticipated a 1:10 transformer with their recommended min load of 470 ohms.
Regards Anthony
"Beauty is Truth, Truth Beauty.." Keats
Sorry, Anthony - but we seem to be talking at cross-purposes.
To me:
* the gain that a cart requires
* is a completely different issue to the loading which delivers the cart's optimal sound.
But that is because I use an active head amp with an MM phono stage - rather than a SUT. Or I use an ss MC phono stage which has the required gain for the LOMC cart.
When I said that a 1:15 SUT would be needed ... it's simple maths. An MM phono stage typically has a 40dB gain (100x) so that a typical 5mV-output MM cart delivers 500mV from the phono stage.
Therefore, a 0.35mV LOMC through a 1:10 SUT will only deliver 3.5mV - so the output from the 40dB MM phono stage will only be 350mV.
To increase the output to 500mV (actually a bit more), you need:
* either a 1:15 SUT (so 0.35 x 15 = 5.25mV ==> 525mV output from the 40dB MM phono stage)
* or a 1:10 SUT with a 43dB gain MM phono stage.
Or of course, an MC phono stage with no SUT/head amp ... and a gain of 63dB.
And re. " Benz clearly anticipated a 1:10 transformer with their recommended min load of 470 ohms " - methinks you have misinterpreted the spec.
It clearly says on the spec sheet that came with my Benz LP " min load 470R ". IOW - minimum !
They don't specify a maximum - but it is interesting to note that Herr Lucaschek ("Mr Benz") produces an MC phono stage which only offers 47k - as that's what he thinks the Benz wood-bodies sound best at.
My own experiments (because I was able to change loading independently of gain) was that 47k gave too loose a bass on my Bob Marley records. 470 ohms was too 'closed in' - but 3300 ohms gave the optimum balance between 'soundstage air' ... and tight bass.
For sure. I just started this thread to inform people of the reissue of the QS mc step up. There aren't many decent ones out there anymore.
I have a 1990s vintage Quicksilver preamp w built in MM phono. I keep it for back up and because it's so great sounding. Especially after I upgraded some capacitors. I am happy to know Saunders (sp?) is still active.
Edits: 08/04/24
I presume you mean this?
A tube head amp!
A brilliant designer named Trevor Lees (here in Melbourne) designed a tube head amp back in the 80s. I owned one for a short time - but could never get past the background noise it produced (of course - being tube !)
You need jfets for a head amp. :-))
Yes that's it. It was nice but unreliable. Still not as pure sounding as a passive sut. Can't do jfets. I like their silence but that see through holographic texture is not there. I occasionally switch off to solid state but shortly return to tubes.
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