Hi everyone! My first time posting here. I believe no one has ever posted about the difference between the stock output transformer of the TU-8900 and the Lundahl LL2785B, so I thought posting a thread about it could help someone in the market looking to get his first 300B amp and having a dilemma.
About a month ago, I was about to order the TU-8900 with Lundahls already from Victor and we've been exchanging emails about it. I know, most of you won't believe this, but the next day, a package arrived on my porch. It was a TU-8900! My wife just started her new job about two months ago and she asked me what do I want her to get me when she receives her first pay check. I said, a 300B would be nice! She wasn't kidding! I was so excited, but she didn't know about the Lundahl output transformers. And that's fine.
I proceeded and built the amp. It was my first Elekit, but I'm not new to diy stuff. It came with EH 300B tubes and Clear Top 12AU7s. Also ordered VCaps for it as well. I knew it requires a lot of time to burn in before I can really judge it, but I had to get the Cossor WE300B from Victor. They came in quick and replaced the EH. Right off the bat, the sound is more pleasing to me.
I gave it about 80 hours and I just couldn't stop thinking about the Lundahls. I emailed Victor and ordered the Lundahl LL2785B. Oh boy, it came so fast! He shipped it Monday and I received it Tuesday at 3:30 PM. Installed them and I was speechless, literally, on what I heard. The LL2785Bs are just next level in performance. And yes, I know it's too early to judge them still (I have only about 20 hours on them), but it's very good sounding. I'm not saying that the stock transformers are bad, especially if this is your first 300B amp (the case for me), but the Lundahls are more musical than the stock. Almost more of everything. The three biggest differences for me are wider soundstage, more 3D sounding (I can hear some instruments like they were coming from the back of my seat), more detailed, and the bass is so much better!
I will continue to burn them in as the Vcaps requires about 300-400 hours (based on what I've read) and I will post my impressions here later.
About a month ago, I was about to order the TU-8900 with Lundahls already from Victor and we've been exchanging emails about it. I know, most of you won't believe this, but the next day, a package arrived on my porch. It was a TU-8900! My wife just started her new job about two months ago and she asked me what do I want her to get me when she receives her first pay check. I said, a 300B would be nice! She wasn't kidding! I was so excited, but she didn't know about the Lundahl output transformers. And that's fine.
I proceeded and built the amp. It was my first Elekit, but I'm not new to diy stuff. It came with EH 300B tubes and Clear Top 12AU7s. Also ordered VCaps for it as well. I knew it requires a lot of time to burn in before I can really judge it, but I had to get the Cossor WE300B from Victor. They came in quick and replaced the EH. Right off the bat, the sound is more pleasing to me.
I gave it about 80 hours and I just couldn't stop thinking about the Lundahls. I emailed Victor and ordered the Lundahl LL2785B. Oh boy, it came so fast! He shipped it Monday and I received it Tuesday at 3:30 PM. Installed them and I was speechless, literally, on what I heard. The LL2785Bs are just next level in performance. And yes, I know it's too early to judge them still (I have only about 20 hours on them), but it's very good sounding. I'm not saying that the stock transformers are bad, especially if this is your first 300B amp (the case for me), but the Lundahls are more musical than the stock. Almost more of everything. The three biggest differences for me are wider soundstage, more 3D sounding (I can hear some instruments like they were coming from the back of my seat), more detailed, and the bass is so much better!
I will continue to burn them in as the Vcaps requires about 300-400 hours (based on what I've read) and I will post my impressions here later.
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Apparently that is so wrong, someone measured it last week per my request and it was 0.1% or so.
Even so, what I am having now is the cleanest amplifier ever that I have had and heard. The performances is down right the best I have ever had the pleasure to own. This is driving my Sennheiser HD800S
Even so, what I am having now is the cleanest amplifier ever that I have had and heard. The performances is down right the best I have ever had the pleasure to own. This is driving my Sennheiser HD800S
I'm sure you will like them. I'm at about 40 hours on my Lundahls. When they hit about 5 - 10 hours, they sounded a little forward and harsh on the upper mid frequencies. But it slowly went away at 25 - 30 hours. It could also be from the VCaps which only have about 100 hours on them.
I can't wait to hit around 300 hours to really judge the amp. But so far, it's been a wonderful experience. Rediscovering music all over again.
I can't wait to hit around 300 hours to really judge the amp. But so far, it's been a wonderful experience. Rediscovering music all over again.
How are you measuring them?
Are you using an oscilloscope? Did you look at the square waves?
This is what I'm talking about -
Boyuurange / Reisong A50 300B Tube Amp Advanced Mods Part Three - YouTube
I have attached .pdf Spec Sheet for TU-8900 from hificollective.co.uk Elekit TU-8900E & TU-8900VK 300B / 2A3 Single Ended Tube Amplifier kit | HIFICollective
Even the TU-8600 spec sheet is THD 10%...So if someone has a scope then post what your unit is outputting....As Victor said..."Only your ears can tell you"
I don’t read those kinda specs even though I should. If reviews are good then my ears and heart decide.
I have over 300 hours on 8900 stock core so pretty sure it’s baked. From everything I have read this will be substantial upgrade. Victor was kind enough to upgrade my 2785B so I could use it in my 8600 and 8900.
I have over 300 hours on 8900 stock core so pretty sure it’s baked. From everything I have read this will be substantial upgrade. Victor was kind enough to upgrade my 2785B so I could use it in my 8600 and 8900.
In general, I would tend to agree, as many a $tereophile tube amp review with John Atkinsons published measurements have confirmed. Only in the absence of auditioning a product, subjective descriptions and specs are all we have to go by when we want to try to speculate where the product fits with what we own and or have auditioned.
@mp9, agree 100%
@chauzza, yes and I still stand by it. In my experience whenever there is a device no matter what it is or its function, and its compatible with "x,y,z" there are designs that have to compromise to make it compatible.
If you have never heard a 300B in another amp or a 2A3 even in the same amp, you could be happy with the sound - again depending on your experience and listening habits. 300B has all the traits its known for, good midrange, extended highs but still warm and bass.
When I move the same Cossor 300B tube from the 8900 to the 8600, soundstage expands, there is more clarity in the music, not clinical or sharp but it brings to attention what was "veiled" over in the 8900. When comparing I moved the same 300B and RCA clear tops. The difference of course is still the amp itself and 12AX7.
Just to be transparent, my 8900 has standard core, TKD pot, ODAM caps, whereas my 8600 has standard core, Takman 2% and Audience Auricap, stock pot. I will let you decide which has better parts
In my opinion the 8900 excels with 2A3, whereas 8600 (of course since it only handles 1 tube type) excels with 300B. For those unsure as to which amp, speak to Victor first but also check your speaker sensitivity. If I has 87 db speakers then I would seriously consider Sun Valley SV1616D (to be honest I am fighting the urge to put my name on the order list for it). Hashimoto opt with 300B...... *droool*
@chauzza, yes and I still stand by it. In my experience whenever there is a device no matter what it is or its function, and its compatible with "x,y,z" there are designs that have to compromise to make it compatible.
If you have never heard a 300B in another amp or a 2A3 even in the same amp, you could be happy with the sound - again depending on your experience and listening habits. 300B has all the traits its known for, good midrange, extended highs but still warm and bass.
When I move the same Cossor 300B tube from the 8900 to the 8600, soundstage expands, there is more clarity in the music, not clinical or sharp but it brings to attention what was "veiled" over in the 8900. When comparing I moved the same 300B and RCA clear tops. The difference of course is still the amp itself and 12AX7.
Just to be transparent, my 8900 has standard core, TKD pot, ODAM caps, whereas my 8600 has standard core, Takman 2% and Audience Auricap, stock pot. I will let you decide which has better parts
In my opinion the 8900 excels with 2A3, whereas 8600 (of course since it only handles 1 tube type) excels with 300B. For those unsure as to which amp, speak to Victor first but also check your speaker sensitivity. If I has 87 db speakers then I would seriously consider Sun Valley SV1616D (to be honest I am fighting the urge to put my name on the order list for it). Hashimoto opt with 300B...... *droool*
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Yes, this is my first and only 300B amp, my other gear consist of EL34, KT-88, etc. based amps. But I have tried a pair of KenRad 2A3s on my 8900 and they were wonderful! And even with only 3.5 watts, it's plenty for my 101 db speakers. I just prefer the sound signature of 300B. Or maybe I just didn't give the 2A3s enough time. I will try them again today and see.
Very interesting, I thought the 8900 is very revealing already. I guess there's only one way to find out (get an 8600).
Thanks for your pointing things out.
Very interesting, I thought the 8900 is very revealing already. I guess there's only one way to find out (get an 8600
).Thanks for your pointing things out.
I think it goes back to what we individually hear and like. As I mentioned in my building thread, swapping 300B for 2A3 made a huge and better difference. Sounds were jumping out in 3D or imaging I have never experienced. Glad to hear about your Ken Rad 2A3 but I wonder if that is causing you to prefer 300B? I have NOS RCA 2A3 in the mail. Will be interesting to compare this to Cossor 2A3 and also Cossor 300B in 8900.
Maybe it is. I guess I should try the Cossor 2A3s and see how it compares. I believe Victor offers two kinds of 2A3, which ones did you get?
I put in the Ken Rad 2A3 while writing this, and it's much better than what I heard before. This is the first time I've tried it with the Lundahl transformers.
I put in the Ken Rad 2A3 while writing this, and it's much better than what I heard before. This is the first time I've tried it with the Lundahl transformers.
I bought the vanilla 2A3 from Victor, not the WE2A3 and for something relatively that cheap I am amazed at what I am hearing. I have many power tubes and other tube amps that support el34, kt66,kt120 etc but to my ears 2A3 bests them all, yes I do lose bass and volume but I don’t rock as .I used to