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Phono Input or new Phono preamp?

Some of you may have been following my recent post regarding my foray into Analog. After much consideration and loads of helpful advice, I have decided to purchase my first Turntable setup.

The turntable is going to be a VPI Classic I and I am seriously considering the Dynavector 20XH Cartridge. My current Amp/Pre is a Musical Fidelity KW-500 Integrated and a pair of Focal/JMLab 1027be speakers.

The Phono input on the KW-500 is MM (2.5mV - can't seem to find the gain figure published anywhere). From what people have advised so far, this input should be able to handle either a MM or a MCHO cartridge. With the Dynavector 20XH rated at 2.8mV, it seems like a good match but again, I'm completely new to this.

Because the KW-500 was such a limited production piece (500 units), there is very little mention of it's performance as a phono preamp anywhere else on the net. My concern is that I don't want my existing phono input on the KW to be the weakest link in the analog chain right out of the gate. If this is the case, I'd really like to consider the possibility of a dedicated Phono preamp.

I'm looking for opinions on whether you all think I could get a better preamp for somewhere in the $500-$800 range than what I can currently get out of my KW-500 phono input. If I WAS to go with a dedicated phono pre, I would likely also then have the option of going with a MCLO cartridge (ie. Dynavector 20X 1mv Special). Does the 20x 1mV tend to fare more favorably than the 20XH (2.8mV)? In what ways does it's sound vary (for anyone with first hand knowledge of the two)?

Any advice is greatly appreciated!

-gh0st
fatgh0st
maineiac
649 posts
 
Sounds like you are getting down the road with vinyl. I started out using the MM section of my integrated first with a HOMC benz glider then a clearaudio maestro MM. This was certainly excellent for getting going, getting used to my turntable, and learning again about vinyl. I cannot speak to the kW's phono but we all know that MF makes some great gear. I am sure it will be very good to get going with and then you can figure out the landscape better and make a move. I did end up with a good stand alone phono and a MC cart which I love but I am glad that I took my time along the way. At this point, spend as much as you can on VINYL LPs!!
fatgh0st OP
43 posts
 
For what it's worth, here is the product detail (PDF format) for the KW-500. Page 10 has the specs for the phono input. No gain mentioned, but it does have the 'Overload Margin'. Not sure what that is...

http://www.musicalfidelity.com/downloads/archived-manuals/English/kW500.pdf

-gh0st
inna
7,141 posts
 
This is none of my business but I am starting to be concerned about your expenses. It can get out of hand very fast. Careful.
raquel
841 posts
 
The overload margin is the amount of voltage the phono input can take from the cartridge before it overloads (saturates). The 29 db. reported in the owner's manual is an excellent figure - 20 db. is common with high-end phono stages (the higher, the better).

However, it does not appear that the phono stage in your integrated allows you to vary the load to accommodate the varying electrical parameters of different cartridges (it's set for 47 kOhms, which usually works with MM cartridges, but not always). This is a serious handicap and reason alone for you to look at stand-alone phono stages.

The Dynavector 20X 1mv Special is not a low-output MC. Low output is typically defined as less than 0.5 mv., with 0.3 mv. being considered a typical low-output MC. It's easy to understand why low-output is in theory better - the lower the mass of the coils or magnets, the lower it's output, and the more easily the stylus can move and track the grooves - it's got less mass to move. So, ironically, the lower the output of the cartridge, the more dynamic and "fast" it is. The problem is that the lower the output, the better the phono stage needs to be to prevent noise from contaminating the very low-voltage, delicate signal coming from the cartridge.

A judiciously chosen stand-alone phono stage will almost certainly improve the performance of your analog rig. My advice to you (and to anyone going down this path) is to avoid phono stages that use tubes in the INPUT STAGE. This is the place where the phono stage amplifies and processes the signal from the phono cartridge - even carefully chosen tubes tend to be too noisy for use as the amplification device of a very low-level signal. For this reason, a lot of phono stages (most Audio Research designs, for example) use a hybrid circuit, with transistors (MOS-FET's, typically) on the input and tubes in the output stage.
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