Greetings,
I am writing in search of some advice about how to refine my system. I currently listen to a pair of Audio Nirvana Super 8s with Amp Camp Amps fed by my computer through a MiniDSP for baffle step compensation. I’ve lived with this system for a year and have determined the areas I’d like to improve:
Tonality
Bass
Headroom
I’d read a lot about tubes on the internet so I visited a local hifi shop to have a listen. I listened to a Dynakit ST-70 and had some reservations. The sound was too thick for my taste; although, I enjoyed the tonal colors, to a certain extent, that it conveyed. My first question is: how do I find a design that will give me color without the syrupy tube cliché?
As for bass, I’ve decided to go open baffle and bi-amp. I want the “thwack”.
My speakers are 98db and the five watts from the Amp Camp seem to not be enough. I listen to it mostly turned almost all the way up and there just isn’t enough headroom. I’m thinking I need at least 20 watts.
I’ve read about DHTs and that seems like a the sound I’d like. I cannot afford a power amp with DHTs at at least 20 watts (and I’m also afraid of too much of that thick sound). I’ve read good things about the My_Ref chipamp and am contemplating that direction. Supposedly it’s very good tonally. I’m thinking a DHT preamp or buffer and, if I like the sound, expand to a phono/DAC output stage in the future.
My second question is: how should I design the gain structure of my system? Would you recommend a preamp or a buffer. What’s going to give me the DHT “glint” without the thickness? Mind you all, I can’t afford any designs with transformers. Also, I’m going to use economical tubes. The 3a5 and 4p1l are on my shortlist (leaning toward the later for its linearity).
My Amp Camp is fine, it has a lot of clarity and impresses my friends, but I find it a little boring. I don’t really find any fault with the Super 8s beyond the bass issue. Maybe someday I’ll try compression drivers, but as long as I’m satisfied with what I have I’ll stick with it. By then maybe I’ll have the wherewithal and knowlege to try an all thoriated-tungsten DHT system.
I don’t understand how I’d be able to live with a flea powered amp with anything less than 107db efficient speakers. At 98db I can’t go loud enough with five watts. Would a preamp with enough gain be able to satisfy my needs with my present power amp? From a meter away my system measures on average 80db.
Cheers,
Y
I am writing in search of some advice about how to refine my system. I currently listen to a pair of Audio Nirvana Super 8s with Amp Camp Amps fed by my computer through a MiniDSP for baffle step compensation. I’ve lived with this system for a year and have determined the areas I’d like to improve:
Tonality
Bass
Headroom
I’d read a lot about tubes on the internet so I visited a local hifi shop to have a listen. I listened to a Dynakit ST-70 and had some reservations. The sound was too thick for my taste; although, I enjoyed the tonal colors, to a certain extent, that it conveyed. My first question is: how do I find a design that will give me color without the syrupy tube cliché?
As for bass, I’ve decided to go open baffle and bi-amp. I want the “thwack”.
My speakers are 98db and the five watts from the Amp Camp seem to not be enough. I listen to it mostly turned almost all the way up and there just isn’t enough headroom. I’m thinking I need at least 20 watts.
I’ve read about DHTs and that seems like a the sound I’d like. I cannot afford a power amp with DHTs at at least 20 watts (and I’m also afraid of too much of that thick sound). I’ve read good things about the My_Ref chipamp and am contemplating that direction. Supposedly it’s very good tonally. I’m thinking a DHT preamp or buffer and, if I like the sound, expand to a phono/DAC output stage in the future.
My second question is: how should I design the gain structure of my system? Would you recommend a preamp or a buffer. What’s going to give me the DHT “glint” without the thickness? Mind you all, I can’t afford any designs with transformers. Also, I’m going to use economical tubes. The 3a5 and 4p1l are on my shortlist (leaning toward the later for its linearity).
My Amp Camp is fine, it has a lot of clarity and impresses my friends, but I find it a little boring. I don’t really find any fault with the Super 8s beyond the bass issue. Maybe someday I’ll try compression drivers, but as long as I’m satisfied with what I have I’ll stick with it. By then maybe I’ll have the wherewithal and knowlege to try an all thoriated-tungsten DHT system.
I don’t understand how I’d be able to live with a flea powered amp with anything less than 107db efficient speakers. At 98db I can’t go loud enough with five watts. Would a preamp with enough gain be able to satisfy my needs with my present power amp? From a meter away my system measures on average 80db.
Cheers,
Y
At the sort of sensitivity you are looking at , tubes like 3A5 and 4P1L may be far too microphonic . Suggest you look into triode connected 6E5P with high efficiency speakers , which is a nice sounding tube and you can get a few watts from a single tube without the need for a driver . Or you could look into a sleeper such as triode connected 6P23P , which is non-microphonic from my experience with this type . It has 11 watts dissipation and is a directly heated beam tetrode rather than a directly heated pentode like 4P1L . Good for around 2 watts with a 5k output transformer
316a
Either your info is not correct, or you already suffer from hearing loss, or it will not take long before you will suffer from hearing loss
Either your info is not correct, or you already suffer from hearing loss, or it will not take long before you will suffer from hearing loss
+1
To avoid that "thick" sound you're completely right to be using DHTs. They will give you the ultimate clarity and lift those veils. But you do want to be using them right through.
Start the chain with an 01A Gen 2 preamp from Bartola valves. This is the best input stage I've ever built, and I've gone through 26, 4P1L, 3a5, 10Y etc input stages in several builds. Then either a 4P1L driver stage into some kind of DHT like 300b or 2a3, or just a 2 stage system with 2 x 4P1L outputs which is what I use. I can't speak for your volume problems - as above, not sure what you need here.
Start the chain with an 01A Gen 2 preamp from Bartola valves. This is the best input stage I've ever built, and I've gone through 26, 4P1L, 3a5, 10Y etc input stages in several builds. Then either a 4P1L driver stage into some kind of DHT like 300b or 2a3, or just a 2 stage system with 2 x 4P1L outputs which is what I use. I can't speak for your volume problems - as above, not sure what you need here.
I go with the guys asking about the specs of your speakers. It seems odd, that you need 20 Watts to drive them.
To the original question: figure out what speakers are right for you and that will tell you what amplifiers you need. Have a look at what JC Morrison did for the 2016 ETF and also the Silbatone system for the High End show in Munich 2016.
To the original question: figure out what speakers are right for you and that will tell you what amplifiers you need. Have a look at what JC Morrison did for the 2016 ETF and also the Silbatone system for the High End show in Munich 2016.
If you want to build with 4p1l and you don't need more than few dB gain, then use line output transformer, carefully chosen operating point, little starved filaments and little mechanical vibration dampening my, and you'll get very quiet preamp . 4p1l will give you a great tonality at a decent price.
Wow, thanks for all the replies. I think I'll start a separate thread in the Pass Labs section to address my issues with the Amp Camp.
Since it looks like my thread has legs let me establish a base line. First of all, I live on Disability and my income is modest. I read someone mentioning transformers. When I say transformers are too expensive I mean it. I realize people are just trying to be helpful but deciding to play with DHTs is already a lofty goal for me. Perhaps people can suggest topologies that may be implemented with capacitors and then later upgrade to iron.
@kaputt: thanks for the advice. I've been eyeing some high efficiency drivers from selenium that rival the drivers in Klipsch Heritage speakers. Low cost and should be lively enough to keep me on my toes. Do you have any links to the Morrison/Silbatone systems? A quick google search didn't yield much.
@andyjevans: How fortuitous to write to you now as the schematic I found of your SEP 4P1L is what turned me on to the valve in the first place. I had to read up on CCS to get a better understanding. Could I possibly use a capacitor in place of the interstage transfo? I was actually looking at the Bartola Valve 4P1L line stage. You seem to hold the 01a in higher esteem. Could I use a UX-201A instead? Would I need a matched pair?
What I hope to get out of this thread is a system road map. I have limited resources and would like to develop a strong vision for what I want to achieve from the outset. But really I don't want to get too bogged down with it because I'm keen to collect vinyl instead.
I'm encouraged to hear that DHTs aren't too thick, but the proof is in the pudding. I need to hear them to really know where to go next. I think I'll like them enough to keep them in the mix, but a Pass SIT project or My_Ref chipamp might be what's called for. I've also got my eye on the Dmitri Nizhegorodov 3a5 phono project.
I don't need to have the best system I just need the right system. The two genres of music I listen to the most are folk/singer songwriter and house. I want to bi-amp to an open baffle woofer to get a strong kick but also want strong tonal colors. I think I'm willing to splurge on amplification the most.
I'd really appreciate patience and maybe a little tutoring as my disability affects my concentration. I love to read about tubes and have picked up the RCA manual, Norman Crowhurst and a few blogs here and there. On the other hand, in the state I'm in I learn best through interaction and not so much on my own.
As I see it now I'll start out with a DHT linestage, then phono and finally power amp if I like what I hear. I'm committed to the line stage because I've put an order in the SSHV group buy.
Since it looks like my thread has legs let me establish a base line. First of all, I live on Disability and my income is modest. I read someone mentioning transformers. When I say transformers are too expensive I mean it. I realize people are just trying to be helpful but deciding to play with DHTs is already a lofty goal for me. Perhaps people can suggest topologies that may be implemented with capacitors and then later upgrade to iron.
@kaputt: thanks for the advice. I've been eyeing some high efficiency drivers from selenium that rival the drivers in Klipsch Heritage speakers. Low cost and should be lively enough to keep me on my toes. Do you have any links to the Morrison/Silbatone systems? A quick google search didn't yield much.
@andyjevans: How fortuitous to write to you now as the schematic I found of your SEP 4P1L is what turned me on to the valve in the first place. I had to read up on CCS to get a better understanding. Could I possibly use a capacitor in place of the interstage transfo? I was actually looking at the Bartola Valve 4P1L line stage. You seem to hold the 01a in higher esteem. Could I use a UX-201A instead? Would I need a matched pair?
What I hope to get out of this thread is a system road map. I have limited resources and would like to develop a strong vision for what I want to achieve from the outset. But really I don't want to get too bogged down with it because I'm keen to collect vinyl instead.
I'm encouraged to hear that DHTs aren't too thick, but the proof is in the pudding. I need to hear them to really know where to go next. I think I'll like them enough to keep them in the mix, but a Pass SIT project or My_Ref chipamp might be what's called for. I've also got my eye on the Dmitri Nizhegorodov 3a5 phono project.
I don't need to have the best system I just need the right system. The two genres of music I listen to the most are folk/singer songwriter and house. I want to bi-amp to an open baffle woofer to get a strong kick but also want strong tonal colors. I think I'm willing to splurge on amplification the most.
I'd really appreciate patience and maybe a little tutoring as my disability affects my concentration. I love to read about tubes and have picked up the RCA manual, Norman Crowhurst and a few blogs here and there. On the other hand, in the state I'm in I learn best through interaction and not so much on my own.
As I see it now I'll start out with a DHT linestage, then phono and finally power amp if I like what I hear. I'm committed to the line stage because I've put an order in the SSHV group buy.
Hi there,
You don't need transformers apart from the output transformer. I have 01A, 26 and 4P1L preamps with LL1660 interstages, plate chokes and Ale's Gyrator. They're all good and possible. Ale's gyrator is probably the most detailed and also has a lower output impedence than plate chokes or a 1 to 1 interstage. So that's what I'm using right now. Save yourself some money. I'd use 01A in preference to 26 or 4P1L but it's close. The 01A has low current - around 3mA - so less of a driver than 4P1L at 25mA. Tubes don't have to be matched as such, it's not like PP amps.
A SIT amp is a perfectly good alternative. The only amp I've heard that comes close to DHT output stages. I have a friend with a SIT with Sony devices and I loved it in my system driven by a DHT.
You don't need transformers apart from the output transformer. I have 01A, 26 and 4P1L preamps with LL1660 interstages, plate chokes and Ale's Gyrator. They're all good and possible. Ale's gyrator is probably the most detailed and also has a lower output impedence than plate chokes or a 1 to 1 interstage. So that's what I'm using right now. Save yourself some money. I'd use 01A in preference to 26 or 4P1L but it's close. The 01A has low current - around 3mA - so less of a driver than 4P1L at 25mA. Tubes don't have to be matched as such, it's not like PP amps.
A SIT amp is a perfectly good alternative. The only amp I've heard that comes close to DHT output stages. I have a friend with a SIT with Sony devices and I loved it in my system driven by a DHT.
I took a quick look at the Amp Camp spec's. It's got a 10k input resistance. That means this output cap of the preamp (computer or what ever) would need a cap around 7.92uF to get down to 20Hz (20.10Hz) Fixing that one thing may fix a lot of your problems (Bass for sure). I would build a preamp that matches your amps rather than start all over. You could play with the amp circuit to get the same desired results. If the output cap of your computer is 2.2uF into 10k gives you a low frequency cutoff point of 72.34uF, use a coupling cap calculator to figure it out once you know what the values are.
@Mark Thanks for looking out. The amp also gives a squeal at startup before the music turns on. I'm not sure what's wrong but you've got me motivated to find out.
@ Andy So from what I gather the advantages of an interstage trans is no plosives or filtration like a capacitor and it gives more headroom. Transcendar makes a 1:1 interstage at 10k that is affordable (and they have a good reputation for performance). How do you determine what the appropriate interstage transformer impedance is for a given tube?
What exactly is the Gyrator, I saw the article on his website but it went a little over my head. Is it a coupling device? Are you using it on your preamp or power amp?
@ Andy So from what I gather the advantages of an interstage trans is no plosives or filtration like a capacitor and it gives more headroom. Transcendar makes a 1:1 interstage at 10k that is affordable (and they have a good reputation for performance). How do you determine what the appropriate interstage transformer impedance is for a given tube?
What exactly is the Gyrator, I saw the article on his website but it went a little over my head. Is it a coupling device? Are you using it on your preamp or power amp?
I don't think there's much to choose between an interstage and a plate choke. With a perfect interstage I'd use that. Advantage is it can be the smoothest option. With a Hammond 126 interstage I preferred it as a plate choke with a Russian FT-3 teflon capacitor, for instance. The LL1660 is a bit of a toss up. As I was saying, Ale's gyrator is a little more detailed than the LL1660. Maybe the LL1660 is slightly smoother, but for me the detail and lower output impedance won over. I would continue to read the Bartola website until it gets more familiar, and combine it with any other tutorials relevant. The Gyrator is basically an active plate load, but a quite evolved one using the best parts we know of.
I would bet that Ale's Gyrator sounds better than a Transcendar interstage. Maybe not by much, but probably better by a little. Haven't heard it but I doubt it's better than Lundahl's LL1660. Hashimoto, Monolith, Tamura or Tango could be another story, but I haven't heard those either.
"Appropriate impedance" is a bit complex. There's usually a trade off between the gap you need for whatever mA of current and the inductance in Henries, so I'd read up on all that stuff.
I would bet that Ale's Gyrator sounds better than a Transcendar interstage. Maybe not by much, but probably better by a little. Haven't heard it but I doubt it's better than Lundahl's LL1660. Hashimoto, Monolith, Tamura or Tango could be another story, but I haven't heard those either.
"Appropriate impedance" is a bit complex. There's usually a trade off between the gap you need for whatever mA of current and the inductance in Henries, so I'd read up on all that stuff.
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