Bottleneck 6V6 competition update
- Thread starter RayP
- Start date
dbishopbliss
New member
I think its this:
http://cgi.ebay.com.my/Horse-Shape-Cake-Pan-Ikea-Teflon-Retro-Red-/350310923200
http://cgi.ebay.com.my/Horse-Shape-Cake-Pan-Ikea-Teflon-Retro-Red-/350310923200
castlesteve
New member
RayP said:
Friday afternoon. getting ready for Sunday. Can someone bring a preamp also as i seem to have an intermittent fault in mine that i haven`t pinned down yet. I`m looking forward to this although i won`t be presenting an entry due to work constraints etc. See you all Sunday, Steve.
Paul Joppa
Moderator
This is starting to sound like a real fun event - wish I could be there. Please post when it's over!
dbishopbliss
New member
My entry is nothing special with regard to the circuit. Even though it is remarkably similar to the design found on the Boozhound Laboratories , I came up with the circuit myself after reading many books and websites throughout the year. I understand the purpose of each resistor and capacitor in the circuit and why I chose the value. Even though I have built several Bottlehead kits and other projects, I never understood anything about what I was putting together. Now I can look at another circuit and actually decipher what is there. This is a big step for me!
I was beginning to think that I would not have an entry either, but have managed to pull it together at the last minute. Then there was a horrible hum that would not have prevented my participating, but certainly would not have allowed me any chance of scoring well. Once I got that worked out, I was disappointed with the sound. Of course, I was playing it with my bench system - an old NEC external CD drive meant for a computer, into a Adcom solid state preamp from the early 90's with Spica TC-50 speakers. I turned the Adcom all the way up (literally) to get a decent level to listen. Problem was, there was huge amounts of audible distortion. In addition, the sound was dull and lifeless.
So, I swapped out the NEC with my ARCAM CD73 (which we will be using for the competition). Big difference! The level put out by the ARCAM was higher than the NEC, so I had to turn down the Adcom but there was still a lot of distortion.
Finally, I decided to bring the system into the home theater room where I have my ART Arrays and my Foreplay III. HUGE DIFFERENCE! I'm sure the Foreplay has more gain than the Adcom, but its only on the third click. The ART arrays are around 92dB while the Spica's are 84dB efficient (just looked that up didn't realize they were that inefficient). Now, the room is filled with sound (as arrays will do) without any distortion. No buzz, no distortion! I'm VERY surprised by the bass. I have yet to run it through some torture tests to see how much there really is, but on regular music tracks it is very pleasing.
Finally, after reading about Steve's linestage not working and our needing a continuously variable volume control I tried something I never tried before. I read somewhere that Lightspeeds should not be used to drive tube amps (not sure why, something about impedance mismatching or something). So, I'm using the Foreplay simply as sort of a tube buffer. I ran from the CD player to my Lightspeed Attenuator to the Foreplay III then to my amp. WOW! I'm really amazed how good this system sounds. I have the parts for another Lightspeed on the way for a different project - now I'm thinking I might want to follow it with a tube buffer.
I will be at Steve's early tomorrow to get things set up. This should be fun!
P.S. The chassis is a cutlery tray and the transformer covers are cutlery caddies from Ikea
I was beginning to think that I would not have an entry either, but have managed to pull it together at the last minute. Then there was a horrible hum that would not have prevented my participating, but certainly would not have allowed me any chance of scoring well. Once I got that worked out, I was disappointed with the sound. Of course, I was playing it with my bench system - an old NEC external CD drive meant for a computer, into a Adcom solid state preamp from the early 90's with Spica TC-50 speakers. I turned the Adcom all the way up (literally) to get a decent level to listen. Problem was, there was huge amounts of audible distortion. In addition, the sound was dull and lifeless.
So, I swapped out the NEC with my ARCAM CD73 (which we will be using for the competition). Big difference! The level put out by the ARCAM was higher than the NEC, so I had to turn down the Adcom but there was still a lot of distortion.
Finally, I decided to bring the system into the home theater room where I have my ART Arrays and my Foreplay III. HUGE DIFFERENCE! I'm sure the Foreplay has more gain than the Adcom, but its only on the third click. The ART arrays are around 92dB while the Spica's are 84dB efficient (just looked that up didn't realize they were that inefficient). Now, the room is filled with sound (as arrays will do) without any distortion. No buzz, no distortion! I'm VERY surprised by the bass. I have yet to run it through some torture tests to see how much there really is, but on regular music tracks it is very pleasing.
Finally, after reading about Steve's linestage not working and our needing a continuously variable volume control I tried something I never tried before. I read somewhere that Lightspeeds should not be used to drive tube amps (not sure why, something about impedance mismatching or something). So, I'm using the Foreplay simply as sort of a tube buffer. I ran from the CD player to my Lightspeed Attenuator to the Foreplay III then to my amp. WOW! I'm really amazed how good this system sounds. I have the parts for another Lightspeed on the way for a different project - now I'm thinking I might want to follow it with a tube buffer.
I will be at Steve's early tomorrow to get things set up. This should be fun!
P.S. The chassis is a cutlery tray and the transformer covers are cutlery caddies from Ikea
Grainger49
New member
John,
Is that a prototype Stereomour?
Is that a prototype Stereomour?
Paul Joppa
Moderator
Dude, that's what it's all about. Congratulations!dbishopbliss said:
There's a buffer in the works - preliminary design but not prototyped yet. Doc B. has the cathode follower buffer we were working on a while back but we think we can do better sonically. :^)
dbishopbliss
New member
Another great event hosted by Steve. As always, thank you.
I think everyone was very happy with all the entries and disappointed for those amps that didn't survive the trip. It goes to show you can make a more than decent sounding amp for less than $200. John's amp that won (the one in the horse-shaped cake pan) was also the least expensive - $143 including tubes!!! I want to review his schematic some more and see what changes I can make to improve my amp.
The bad luck award goes to Ray. What are the odds of having TWO amps work during setup, then having both amps lose a channel during the actual competition? Maybe Ray's amps have performance anxiety.
I'm looking forward to the next competition. While we haven't decided what it will be, I like the idea of making a budget line-stage. We should not allow anyone to submit a Foreplay I or Quickie. Although, it might be fun to include them in the judging - I have a stock Foreplay I that we can use.
I think everyone was very happy with all the entries and disappointed for those amps that didn't survive the trip. It goes to show you can make a more than decent sounding amp for less than $200. John's amp that won (the one in the horse-shaped cake pan) was also the least expensive - $143 including tubes!!! I want to review his schematic some more and see what changes I can make to improve my amp.
The bad luck award goes to Ray. What are the odds of having TWO amps work during setup, then having both amps lose a channel during the actual competition? Maybe Ray's amps have performance anxiety.
I'm looking forward to the next competition. While we haven't decided what it will be, I like the idea of making a budget line-stage. We should not allow anyone to submit a Foreplay I or Quickie. Although, it might be fun to include them in the judging - I have a stock Foreplay I that we can use.
Some comments and lessons learned from last Sunday's event which I really enjoyed.
The scoring was incredibly close in the first round. A change of a single vote would have changed the order completely. I found that some amps suited certain music better than others.
Oddly enough, after the closeness of the 1st round, there was no doubt in the final round that John's amp was the winner and also the cheapest at under $150.
We definitely had problems getting the sound level correct for each entry and we need to re-think how we do this for next year's competition. Since it was a nice day and the world outside was quite active, there may have been noises other than the test tone affecting the db reading. Let's play with this aspect during our future meets to develop a better method.
I appreciate our team of judges being so quiet during the music and taking this event seriously.
Although I was not judging, I found it very difficult to pick an order during the first round and perhaps at future meets, we can talk more about scoring techniques. For myself, I think in future I would do a preliminary score just after the first piece based on first impressions and then adjust as I heard further music.
Finally, could those who submitted entries and would like their schematics posted, please email them to me. Now I have arrived at a house with a fast internet connection, I can work on getting them posted. And no, I can not see any volcanic ash in the beautiful blue sky near Whitby.
ray
The scoring was incredibly close in the first round. A change of a single vote would have changed the order completely. I found that some amps suited certain music better than others.
Oddly enough, after the closeness of the 1st round, there was no doubt in the final round that John's amp was the winner and also the cheapest at under $150.
We definitely had problems getting the sound level correct for each entry and we need to re-think how we do this for next year's competition. Since it was a nice day and the world outside was quite active, there may have been noises other than the test tone affecting the db reading. Let's play with this aspect during our future meets to develop a better method.
I appreciate our team of judges being so quiet during the music and taking this event seriously.
Although I was not judging, I found it very difficult to pick an order during the first round and perhaps at future meets, we can talk more about scoring techniques. For myself, I think in future I would do a preliminary score just after the first piece based on first impressions and then adjust as I heard further music.
Finally, could those who submitted entries and would like their schematics posted, please email them to me. Now I have arrived at a house with a fast internet connection, I can work on getting them posted. And no, I can not see any volcanic ash in the beautiful blue sky near Whitby.
ray
I have uploaded some photos which you can see at http://829b.com/6v6entries.aspx and I will post the remaining schematics as they arrive.
This was such a fun competition and I would urge all of you to try something similar in your geographic location or perhaps just build one for yourself if you are experienced in building amps. These amps sounded really great and it was amazing what could be achieved for $200. It was particularly interesting to have the cost of parts restriction and it really makes you ponder when you have to make tradeoffs; do I spend $$ here or there.
Many thanks to all of those who took part and to Steve for hosting.
ray
This was such a fun competition and I would urge all of you to try something similar in your geographic location or perhaps just build one for yourself if you are experienced in building amps. These amps sounded really great and it was amazing what could be achieved for $200. It was particularly interesting to have the cost of parts restriction and it really makes you ponder when you have to make tradeoffs; do I spend $$ here or there.
Many thanks to all of those who took part and to Steve for hosting.
ray
