Musical Fidelity Tubalog

[jean-paul]

Does anyone know more about the Musical Fidelity Tubalog DAC ?
I have one since a week and after some basic mods it sounds better than my PCM1710U DAC but not really very good.
I called the dutch importer and to my surprise he said that there isn't a service manual for this model !?!
He obviously was embarassed to tell me this. He made an attempt by calling MF England but they gave the same answer. No schematic, no manual. The DAC is made in 1994.

DAC chip and digital receiver are Sanyo types. Unfortunately MF has cut off the typenumbers but I could still see the Sanyo brandname. Apparently they were ashamed using Sanyo or something like that. DAC chip is a Sanyo 24 pin DIL chip and probably it has the 4Fs digital filter in it. The receiver is a 42 pin narrow DIL. Opamps after the DAC were NE5534AN's ( now OPA627BP ).Output stage has Russian 6H23Pi tubes in it.

Any info is welcome, I tried to find datasheets of Sanyo audiochips but Sanyo simply deletes old datasheets.
There seems to be a Mk 2 version of this DAC ( I have a Mk 1 ) and I am curious what MF has changed in it. As usual with old MF gear there are some cost cutting design flaws in it ( like feeding the tubes filaments with the same voltage the opamps use ) that I want to change. In good tradition it also gets hot like the A1's and A100's


I thank you in advance,

Jean-Paul

[ktigerb]

Hi Jean-Paul
Did you ever get any reply on the Tubelog ???
I now have one also but needs repair , no audio out .
regards
keith birss

[SteB]

Hi Jean-Paul,
how do your Burr Brown op-amps sound, i was thinking of Analogue Devices ad825 more appripriate
which as far as i gather are not as dark sounding as the opa627bp and olso good bit cheaper.

Aslo has anyone done any worthwhile mods apart from the op amps? can't find much mod info on this lovely 16 bit tube dac.
site below has some mention of tubalog with cd950(clock mod)
I use phillips cd950 for transport which sounds average with tubalog imho no great bass definition,less so with discmagic i had, but this gave it more musicality and hooked me like my parents early 80's PYE Audio music centre (made to look like seperates on black ash rack) with turntable,my reference in fact for all audio components-eminently listenable and addictive, rich musical sound ,imageing not bad the headphones seemed to dissappeared,not much detail though but enough to fool me into looking around the room for the extraneous noises made in the recording studio- oh the memories.


http://www.1388.com/doctor/jonopinio...1/pg2/pg2.html
http://www.1388.com/doctor/jonopinion/23042001/
http://www.1388.com/doctor/jonopinio...1/pg2/pg2.html

all opinions are IMHO

[jean-paul]

Hi SteB, I use OPA627BP because when bypassed correctly it is a hard one to beat. I would not use a dual opamp in a DAC where the designers were so carefully to choose single opamps

I sold the DAC in the meanwhile, it was finished and then the fun is over.

[tone arm]

hi keith,congratulate for owning 1 of the world best dac,tubalog.
if no sound is the problem,ceck with the tube,it may hav worn,juz swap it to ecc88 or 6dj8. if still no sound,ceck its continuity analog domain,after the ops amp,the output before tube buffer. see if theres signal. good luck.

[tone arm]

Hi guys,
anyone out there own tubalog and wanna get rid of it,pls get me inform,i love this dac,nothing close to it.
hp no 93848943. S'pore.

[ash_dac]

Hi,

Not mine but for those interested!


http://cgi.ebay.co.uk/MUSICAL-FIDELI...QQcmdZViewItem

Kind regards,


Ashley.

[onechance]

Originally posted by tone arm
Hi guys,
anyone out there own tubalog and wanna get rid of it,pls get me inform,i love this dac,nothing close to it.
hp no 93848943. S'pore.

Hi Tone Arm, did you ever get your Tubalog? I have a 1997 model with very low hours, full documentation as well. Are you interested? I'm in Adelaide Australia so transport should be easy and fairly cheap. Cheers, IAn

[tone arm]

Hi onechance......sorry for the late late late reply.....i was out of action for quite awhile, juz making a comeback with audio recently... anyway, juz checking with u again...do i stand a chance with that MF Tubalog? Or have u come across with any MF Digilog? I am still keen with both. Thank u.

[hew128]

Hi ToneARM,

I sold my Digiloc recently as it seem to lose control when the material gets complex. Prefer the Marantz CDA94 after it was recapped and the Deltec PDM1S1 to the Digiloc.

There is someone selling a Tubalog in Kedah Malaysia for RM600 but pickup only.