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Best Valve pre-amp match for ME 550 amp

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Its unfortunate that our friend Zaphod is getting somewhat anxious by this whole affair, which in fact is a pioneering spirit destined to be initiated 'outside the square' of convention..., and was not forseen in its inception of having the potential to create what appears to be severe 'angst' to our friend Zaphod. :confused:

I did rather enjoy the valve preamp sound from that very 'budget' buffer amp tho, however I do suspect that the ME25 will sound better. I will just have to audition it and hear for myself...The ME550 is rather good I must say, and I have not played it, only once or twice, since I had it refurbished and modified to be more like an upgraded model by Peter Stein. :)

The valve buffer does its magic in the NAD T773 rather well though, transparancy and soundstage is quite good and clear, the ME550 just does it better...:sax:
 
Just tried using the NAD T773 (front-main stereo channel) pre-amp connected to Guanzo Valve Buffer and ME550. LP disc sounds crisp, clear and detailed - very CD like - in fact it sounds more like a CD - than a CD - in terms of detail and dynamic crisp presence etc... like a boron, ruby or diamond cantelever feel to it...

I did modify a few things tho on the first valve buffer which is what I used this time :)

Be interesting to compare with ME25 ..., I imagine it would reveal a more airy soundstage with dynamic realism and inky black background silence ... hmmmmm
 
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...must be the recordings...; or because of the variation in impedance, could some sounds/frequencies be more dominant than others?

...well, I have to be honest with my observations --- and they were two effects when combining the NAD T773 pre-amp with valve buffer with different LP's.

...anyway, just very loose experimentation while awaiting the ME25, and valve pre-amp kits to arrive and be put together and auditioned with transformer coupling to lower impedance and compare. The valve buffer on its own was still a very interesting result. Its early days yet for a defined conclusion.
 
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ahhhh, thats better --- it was just an adjustment consideration I didnt make --- sounds quite good now :)

...doing an A/B with the NAD main amp and ME550 : in that setup with NAD preamp/valve buffer, the ME clearly is more dynamic, crisp and meatier sounding...

Goes to show that the ME 550 will still sound better even when not optimally matched impedance wise...I quite like the ME --- I must say --- worth having !!
 
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OK, I also did an A/B with-and-without the valve buffer connected to the preamp out, and the difference was like chalk and cheese. Clearly, the valve buffer improved the sound considerably; there was much more presence, realism, transparancy, detail and sense of natural timbre in the sound. The midrange and top-end extended - with greater realism in vocals, while the boomy bass tightened. This is why I am so keen on incorporating valves....
 
I have to ask those that respond; that this is NOT a 'valve-bashing' thread, but one where I am looking for practical valve pre-amp solutions.

If you dont have any practical ideas that are of value in keeping with the theme, then please do not comment with any negative insinuations

I only wish those who have some genuine practical input to a solution to respond. I will not bend to the personal wills of those who are opposed to my idea/goal.

I encourage those who have given practical input and suggestions to continue to do so - its about progress and moving forward & also benefits others in turn.

I am grateful for the genuine input and ideas others have presented since the beginning of the threads inception, and will begin to implement them, I have been busy to date with other concerns, but am now in the process of putting one together. I will begin with the Jadis inspired copy first..., and then Aikido most likely.
 
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Hey ... this looks rather good: Tube Phono Line Pre Amplifier Fully Complete Kit incl Enclosure and Tubes | eBay

German designed/produced : 100% good feedback : very nice looking design : low impedance 330ohm : hmmmm

This one is even lower impedance: it seems only 32 ohm : http://www.ebay.com/itm/Mini-Dual-T...pt=Vintage_Electronics_R2&hash=item4165b3542a

Found the german source on this site: Tube Preamp

Take note, that the 'Matisse buffer' I tested is mentioned on this site a number of times, as well as the Quad 22 and other preamp I looked at on ebay from chinese sources...

...interesting....

For those that have some know-how of tube amps; which ones look the most promising on the vintage-tube site for what I am looking for??
 
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Peter Stein - the designer/producer of ME amps - never tried to talk me out of any idea I had - and if anything, came up with a better variation of the idea; in fact he was always in some way helpful, co-operative and a gentleman - giving of his time; volunteering & sending information etc...I have a lot of time for that man.

He knew I was going to build a valve pre-amp when I contacted him, and was very helpful with any information I wanted. He was not opposed to the idea at all.

Its probably important that others know that - he is very helpful and open-minded to whatever innovative idea one might have; and if anything will give a better understanding of what you are attempting and a better variation to your plan and will try to increase your knowledge of what you are doing for best results.

He even modified my ME550, so that it was easier to put silver strips in there : in addition to what needed fixing - when I mentioned it to him. He was not against the idea - and even gave me further information on placement for best results. He did an excellent job at refurbishing/modifying my ME550 to a plus version.
 
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I am at a loss to understand how much electronic gear is connected in tandem in order to feed the ME 550 amplifier via your turntable.The NAD is a home theatre item and would require a phono pre-amp,then the (unspecified gain and input or even o/p impedances)valve buffer stage.Douglas Self has discussed the effects of source resistance in ''Electronics World" of May 2003 and that article provides useful information on the subject.Peter Stein may have other ideas as the topology of the ME amplifiers could be quite different from the 'Blameless' configuration,developed by Self.Of course there are techniques that allow valve stages to provide a very low source impedance ,but even with a cathode follower,the usual complete preamplifier design would not appear to be well suited to the ME 550.It is good practice to keep things as simple as possible and the matching ME 25 appears to be an ideal choice,rather than what appears to be a valve based product requiring additional circuits.
 
I have just been experimenting. At one stage I connected the preamp section of the NAD just to see what it sounds like. At present, I am auditioning only the NAD565BEE CD player via the Mattise valve pre-amp and ME550. Sounds fairly good. I imagine it might sound better with proper configuration, but nothing stands out as being 'wrong', one probably might consider it 'not ideal' if a better sound was auditioned, ....as the impedance is not matched.

I like the valve sound, so I wish to pursue it. I think simply using transformers or cathode follower, or in fact the german hybrid design I listed in a post recently ... may be the go ... I understand what you and others are saying, and I am waiting on Zaph to get back to me regarding audtioning the ME25 as per his offer. I will still however, regardless of whether I own or don't own a ME25 - pursue building a valve pre-amp to suit. Also, its a challenge, which I will not turn from. The more that state its impossibility, the more I feel motivated to find a solution.

Just being in the possession of an ME25 will not stop me from pursuing this, as I like the valve/SS amp sound.

As it stands, I like the sound from the valve Matisse buffer, but I also know it can be improved on a fair bit.
 
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...am I reading correctly? Did he say below 1 ohm?

"The frequency response is nearly flat, it doesn't matter if the load is 150 or 32 ohm, the internal resistance is below 1 ohm, the THD are typically for a tube with a lot of second harmonics (K2). They only rise over 5 % even at the output's limit, and below this threshold they decrease linear below 0.1 %."

If that is correct, then surely this would be perfectly matched to the ME550...with regards to impedance.

...but then again, he does say min output impedance = 32 ohms. Still, its pretty low...

Mini Dual Tube Headphone Amp "Blue Velvet" Edition from Mr Nixie | eBay
 
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