exactly my input tube of the moment , very smooth and 3d sounding ( microphonic effect ?) i have tried the 2P29L and the 6E5P and like the 6E5P better for me it's a very strong driver tube and works fine with a 300B . but the 26 have a magic distorsion making all kind of music souds good . all the faster pentode in pseudo triode mode tend to be a little nervous and don't stand bad recordings..
on the cheap and easy drivers i have also tried the small triode 6N6P is also very good to try . lots a power low RP and silent ..
I have a selection of driver stages for my EL12n outputs, which have a gain of 18 in triode enabling a 2 stage SE amp.
So listened to the 2P29L all day yesterday and liked it, and it's still there today. Quite a different sound from the 26 but nevertheless a good sound, and not bland in any way. I'm going to tweak it and maybe try and get some more warmth into it with e.g. a PIO coupling cap instead of the present teflon FT-2 which is detailed and neutral. The FT-2 caps suit the 26 very well.
Have any 2P29L users played around with coupling caps?
- The 26 in filament bias is probably my favourite because of the piano tone and vocals. It's not quite as detailed as other options.
- The 10Y in principle is better still but I've converted that to 47 at the moment
- The 47 in filament bias is probably the most neutral, but lacks the 26's moments of magic.
- The 2P29L in filament bias is still one of my choices. It's a little thinner and brighter but very clear and quite involving in its way. Easy build.
- The 6AH4 is good for an indirectly heated tube and very detailed with low Ri of 1.8K. Another easy option though DHTs are better.
So listened to the 2P29L all day yesterday and liked it, and it's still there today. Quite a different sound from the 26 but nevertheless a good sound, and not bland in any way. I'm going to tweak it and maybe try and get some more warmth into it with e.g. a PIO coupling cap instead of the present teflon FT-2 which is detailed and neutral. The FT-2 caps suit the 26 very well.
Have any 2P29L users played around with coupling caps?
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i'm posting again because I just got a new pair of proper speaker stands to replace my rubbish DIY ones. Atacama SLX 600, very solid.
The sound is quite transformed - cleaner, more solid, better bass, dramatically better soundstage. The 2P29L is sounding great with these new stands - the previous thin/bright sound has pretty much disappeared. Quite an important discovery for me. I'm loving the new sound. Better in every way.
The sound is quite transformed - cleaner, more solid, better bass, dramatically better soundstage. The 2P29L is sounding great with these new stands - the previous thin/bright sound has pretty much disappeared. Quite an important discovery for me. I'm loving the new sound. Better in every way.
Hello Francois. Present system is as follows:
Source - everything is on my Mac Pro, ripped CDs, internet, TV. And volume control in software.
DAC - AK4490 with upgraded LM6172 output op-amp.
Amp - 2 stage SE, EL12n outputs in triode, a variety of external input stages including 26, 47, 2P29L and 6AH4 which I can rotate.
Speakers - Mission 761 on Atacama SLX600 stands.
It's a very simple, low parts count system. But all high quality parts like teflon and DC Link caps, NOS resistors. No preamp needed.
Source - everything is on my Mac Pro, ripped CDs, internet, TV. And volume control in software.
DAC - AK4490 with upgraded LM6172 output op-amp.
Amp - 2 stage SE, EL12n outputs in triode, a variety of external input stages including 26, 47, 2P29L and 6AH4 which I can rotate.
Speakers - Mission 761 on Atacama SLX600 stands.
It's a very simple, low parts count system. But all high quality parts like teflon and DC Link caps, NOS resistors. No preamp needed.
761 is fairly easy to find in the UK. It has a nice sounding and widely used Vifa D19 19mm tweeter and a 6.5" mid-bass by Vifa, the smaller magnet C17WG version of the C17WH that Troels G. liked so much. Foam surrounds, paper cone.
http://www.troelsgravesen.dk/C17.htm
http://www.troelsgravesen.dk/C17.htm
Hey!
In need of controlling the volume on my Amp Camp Amp, I also ordered the Nobsound E6 preamp that uses the similar 2J27L, discussed previously in this thread.
In short:
-sounds amazing, complements BLH FE206En really well
-into ACA it hisses quite audibly even from 1-2m
-extremely microphonic, just a brush of the fingers produces a sustained ring. If loud enough, runaway effect.
-hiss and microphony irrespective of volume setting on preamp itself
-only when switching to a gainclone amp with volume pot, and setting the gain quite low on that, are both hiss and mp much repressed.
Upping the gain on the amp, the effect becomes the same as on Pass ACA.
Now I really like the sound, but the main point of it would be to drive the amp camp amp into fostex horns in my case. I heard that russian tubes solve the microphonic issue to a degree, but is the hiss related to tubes, or is the topology simply unsuitable for the Ampcamp stage?
Can it be solved?
Best, Alex
In need of controlling the volume on my Amp Camp Amp, I also ordered the Nobsound E6 preamp that uses the similar 2J27L, discussed previously in this thread.
In short:
-sounds amazing, complements BLH FE206En really well
-into ACA it hisses quite audibly even from 1-2m
-extremely microphonic, just a brush of the fingers produces a sustained ring. If loud enough, runaway effect.
-hiss and microphony irrespective of volume setting on preamp itself
-only when switching to a gainclone amp with volume pot, and setting the gain quite low on that, are both hiss and mp much repressed.
Upping the gain on the amp, the effect becomes the same as on Pass ACA.
Now I really like the sound, but the main point of it would be to drive the amp camp amp into fostex horns in my case. I heard that russian tubes solve the microphonic issue to a degree, but is the hiss related to tubes, or is the topology simply unsuitable for the Ampcamp stage?
Can it be solved?
Best, Alex
I recently completed a 2P29L build for a friend. Essentially the implementation is exactly as per the one on Ale Moglia's website. I implemented a two box solution, with transformers and raw supplies in one box and the other chassis just holding the main circuit. I used the Relaixed relay source select/attenuator for control as it also gives remote control ability and I am familiar with it.
At this point I have built two of these (and two 01a), one for me and one for a friend. My own one is the same circuit, but in a single chassis. I can conclusively say that the two box solution is definitely quieter. This is particularly so in the case of the 01a which is more microphonic than the 2P29L and I believe I will most likely go back and rebuild my own 01a in a two chassis solution. The problem is not grounding, but rather transformer vibration and whatever EM/magnetic fields are within the chassis.
Anyway, the main chassis here is a little unusual - my friend has a love for 70s receivers and asked could I use a chassis for one of these for the preamp. The end result turned out well, I gutted the contents for space, and I removed one of the dials to fit the 7-segment display for the Relaixed source select/attenuator. I couldn't get the green of both receiver display and 7-segment display to match perfectly, but they are close enough. The volume knob is mounted on a rotary encoder for attenuation/source select, all the other knobs are just kept from the original but are not connected.
The PSU box is nothing special - transformers for audio are the 3x along one edge, then the rawDC supplies for the filaments in the middle, and HV maida regulator towards the back. The other two supplies are simple LM7805/7808 for the Relaixed system and the lamps in the receiver chassis.
In the coming while I will do some measurements on the preamp.
At this point I have built two of these (and two 01a), one for me and one for a friend. My own one is the same circuit, but in a single chassis. I can conclusively say that the two box solution is definitely quieter. This is particularly so in the case of the 01a which is more microphonic than the 2P29L and I believe I will most likely go back and rebuild my own 01a in a two chassis solution. The problem is not grounding, but rather transformer vibration and whatever EM/magnetic fields are within the chassis.
Anyway, the main chassis here is a little unusual - my friend has a love for 70s receivers and asked could I use a chassis for one of these for the preamp. The end result turned out well, I gutted the contents for space, and I removed one of the dials to fit the 7-segment display for the Relaixed source select/attenuator. I couldn't get the green of both receiver display and 7-segment display to match perfectly, but they are close enough. The volume knob is mounted on a rotary encoder for attenuation/source select, all the other knobs are just kept from the original but are not connected.
The PSU box is nothing special - transformers for audio are the 3x along one edge, then the rawDC supplies for the filaments in the middle, and HV maida regulator towards the back. The other two supplies are simple LM7805/7808 for the Relaixed system and the lamps in the receiver chassis.
In the coming while I will do some measurements on the preamp.
