TU-8500 phono stage upgrades

I've really gotten the vinyl bug again after finding several large boxes of LPs that I forgot I had, mostly from the 70's. I really am enjoying my 8500 with 8200, always looking for possible improvements. What phono stage upgrades can I make to get even more from the 8500, I love to tweak...Thanks
The 8500 is stock except for the tubes, I'm running Sylvania 12AT7 JAN
 
Another op-amp to roll is the LM4562NA which is an 'ultra low-noise' audio model from TI (think they may inherited when they purchased National Semi). Don't recall what I paid for my pair, but think it was $11. Much cheaper than rolling tubes.

Rolled in a pair of matched JAN Sylvania 12AU7 tubes and am very pleased. Have a pair of Gold Lions to try next, but the Sylvania are excellent. The stock Chinese tubes are really quite bad.

The TU-8500 is a great little preamp.
 
Another op-amp to roll is the LM4562NA which is an 'ultra low-noise' audio model from TI (think they may inherited when they purchased National Semi). Don't recall what I paid for my pair, but think it was $11. Much cheaper than rolling tubes.

Rolled in a pair of matched JAN Sylvania 12AU7 tubes and am very pleased. Have a pair of Gold Lions to try next, but the Sylvania are excellent. The stock Chinese tubes are really quite bad.

The TU-8500 is a great little preamp.


So, I've got some ti-2227 on the way, not sure why, because I like it the way it is, always trying to get the most and the best...LOL...
 
Another op-amp to roll is the LM4562NA which is an 'ultra low-noise' audio model from TI (think they may inherited when they purchased National Semi). Don't recall what I paid for my pair, but think it was $11. Much cheaper than rolling tubes.

Rolled in a pair of matched JAN Sylvania 12AU7 tubes and am very pleased. Have a pair of Gold Lions to try next, but the Sylvania are excellent. The stock Chinese tubes are really quite bad.

The TU-8500 is a great little preamp.


So I'm glad you didn't recommend audiophile capacitor upgrades because I don't believe they have tonal qualities in the signal path. I use WIMA from all my upgrades/builds...
 
Ooops.......... forgot to mention that I went with Victor's top Mundorf EVO SilverGold upgrade caps. Same as in my amp and glad I did. Would have thought that going with the best caps were a given, so not mentioned. Always go with the best coupling caps you can afford. They make as big a difference as tube rolling. As with cables, if you are not able to hear the difference you have my sympathy on one side and my regret on the other (if you can't hear the difference, its free - any cap or cable will do. if you can hear the difference...... it costs).

Also, neglected to mention that I hear some low level of hiss between tracks when listening at loud levels on the MC input when I stand near the speakers with the 2227P opamps. Like you, I like the sound TU-8500 enough, and 99% of my listening is at moderate levels (<75db), that I've not rolled in the LM4562s to see if it might be the tubes or the opamps. Will eventually get there.
 
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So I'm glad you didn't recommend audiophile capacitor upgrades because I don't believe they have tonal qualities in the signal path. I use WIMA from all my upgrades/builds...

After having used my (heavily modified) TU-8200DX with the Amtrans AMCO caps for a couple of years, I thought I would give it a try and ordered a set of Mundorf Supreme EVO SilverGold caps. I was always sceptical about sonic advantages of more expensive caps, and this was the maximum I was willing to spend in order to test my assumptions.

My suspicions were right as I could hardly convince myself that there was any sonic difference. (At the same time, I could hear noticeable differences between different tube brands.)
 
Another op-amp to roll is the LM4562NA which is an 'ultra low-noise' audio model from TI (think they may inherited when they purchased National Semi). Don't recall what I paid for my pair, but think it was $11. Much cheaper than rolling tubes.

Their noise current is a bit on the high side for moving-magnet cartridges, although it will probably still be less than record surface noise. (Ultra low-noise usually means ultra low noise voltage and ultra high noise current.) If you want to support both moving-magnet and moving-coil cartridges, they are a good compromise.
 
good capacitors are soundless. WIMA are excellent.
if they have a sound, it would be in a change of capacitance relative to voltage across it.
old ceramics were poor ( microphonic).
Someone could run tests of various caps for pf vs V. This effect is huge in Mosfet gates as VDS approaches zero.


I like the Wima MKP-10 capacitors in my tube amp builds, solid performers, durable, fit circuit boards perfectly, and best of all they have a pretty red color, :)
 
Whew............. thought I was the only one who purchased caps based on looks. Doesn't matter how it sounds as long as it looks good. That's why I prefer tubes. That lovely filament glow with some occasional blue and even more rarely seen red plate (hopefully, seen no more often then the northern lights here near the south end of NJ). ;) Don't get all that with solid-state.
 
Been listening to a range of cartridges (5x MC & 1x MM) with the 2227P opamps and to my ears, at least to this point-in-time, it makes all the MCs sound about the same. Has a pleasant, linear sound, but......... am guessing is about what one would expect at this $$-level. I'm going to listen for another week to see if the fancy caps need more time (or need to be dipped in epoxy, etc. ;)), then roll-in the next set of opamps to see if that makes a difference. In the meantime, I'm giving some serious thought to a SUT with the capability to adjust the resistive load setting. More in another month when I've heard more.
 
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Been listening to a range of cartridges (5x MC & 1x MM) with the 2227P opamps and to my ears, at least to this point-in-time, it makes all the MCs sound about the same. Has a pleasant, linear sound, but......... am guessing is about what one would expect at this $$-level. I'm going to listen for another week to see if the fancy caps need more time (or need to be dipped in epoxy, etc. ;)), then roll-in the next set of opamps to see if that makes a difference. In the meantime, I'm giving some serious thought to a SUT with the capability to adjust the resistive load setting. More in another month when I've heard more.

Thanks for the feedback. I've rolled in the 2227p's but haven't listened yet, hooked up my Akitika PR-102 while I worked on the 8500 (have left the stock caps in place). Really enjoyng both of these pre-amps. I've been rolling cartridges (MM only) as well. My Orbit came with an Ortofon Red, then tried the ATVM95e, and now the AT3600L ($13). So far, to my ears the AT3600L wins hands down. I'll post again when I try the 8500.
 
My MMs over the past few years have been a V15VxMR, Ortofon 2m Blk & the current AT150Ti. The At150Ti the best of the bunch. However, to my ears, a comparably priced MC is superior to a MM and I'll be selling the AT150Ti in the not too distant future.
I do find a bit of 'noise' between tracks when my ears are next to the speaker. Certainly nothing audible when music is playing at any level.
 
I absolutely love this Pre-amp. For the price and performance It's unbeatable. I bought mine with all the upgrades offered by Victor, like the Mundorf caps, Amtrans AMRT resistors. I decided to with bought a pair of NOS Mullard Backburn 12AT7's in the tube section.

As for Opamp. Hybrid Opamp give the best performance when it comes to a Phonostage. And the best combination ssddi far had been OPA1641 JFET For the input, and OPA1611 Bipolar for the second stage. By far the best sounding out of all the combinations I had tried. It has great noise performance and it has brought my records alive.

I recently posted on here about upgrading the Voltage regulators with great results in my 8500 here. TU-8500 with Sparkos Labs Discreet Voltages Regulators

Im going to try a new set pig hybrids. OPA827 Jfet for the inputs, and Sparkos labs SS3601 discreet opamp for the second stage, should be coming in the mail any day now.

I did try Sparkos SS3602 for both stages and it sounded pretty bad. Very loud hum, hopefully Hybrid does better. The SS3602 are better left in my headphone amp.

By the way! if your going to try hybrid opamp the 8500, The opamp inputs are mixed up. Left channel uses Pins 1 through 4 for the first stage, while the right channel uses pins 5 through 8 for the for the first stage. This picture was taken from the back of the amp, Left channel opamp is on the right, and Right channel opamp is on the left.
 

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Interesting. After a couple of hundred hours of play the noise between tracks on LPs on my 'full house' (all VK options) has gone, which is nice. I do find with the Ortofon Cadenza Black I need the volume up to 11-12 o'clock for what I consider to be the loud side of normal listening. No problem with noise between tracks, so am good. I keep thinking I'll roll in the new TI opamps, but am enjoying so much 2227s that I've not bothered.
 
Same here, It took about sixty to a hundred hours for my 8500 to break in after being built with the 2227s. You can never go wrong with the 2227s.

I have always read that opamp burn in is a myth, But after rolling quite a few, noise is the first thing I notice that changes with time, sound not so much. I even came across a thread of people literally baking them to accelerate break in. I couldn't tell if they were being sarcastic or serious.

Are you using the 8500 in MC or MM gain?