Yea for A1
Also, you can ask at the counter for most anything. I use them for NOS rectifier tubes and various switches. In general however I prefer online suppliers like Digi or Partsconnexion. We are blessed to have these guys close by. If I buy something heavy, I drive down to Burlington to pick it up again avoiding shipping. To me, part of the fun of DIYaudio is getting great stuff dirt cheap.
I have had much fun (and saved a bundle) sifting through their massive collection of transformer pulls to find dirt cheap gems for DIY projects. Also, he carries the entire line of Hammond products at discount prices. You place a deposit and a week later it's there for pick up. Avoiding the shipping price on heavy items is worth the visit.
Also, you can ask at the counter for most anything. I use them for NOS rectifier tubes and various switches. In general however I prefer online suppliers like Digi or Partsconnexion. We are blessed to have these guys close by. If I buy something heavy, I drive down to Burlington to pick it up again avoiding shipping. To me, part of the fun of DIYaudio is getting great stuff dirt cheap.
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nowhere outside of hi-end audio does "the emperors new clothes" offer such salient advice
Guess it's going to be a while till the next meetup. Might as well do this online, during this COVID thing. Itchy gingers and the solder iron beckons.
Got intrigued by this TDA 7297 chip. So I ordered two Ebay kits hooked them up to a couple of LT1083 regulators and I now have a 4 channels of about 7 watts each. Plenty for near field listening. I now have my bookshelves biamped.
Got intrigued by this TDA 7297 chip. So I ordered two Ebay kits hooked them up to a couple of LT1083 regulators and I now have a 4 channels of about 7 watts each. Plenty for near field listening. I now have my bookshelves biamped.
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I am going to break this apart this weekend and put each 7297 and regulator right next to the speaker and eliminate the long cheap speaker cables.
I am also using a TPA3116D2 Class D chip amp for my subwoofer. Total cost of $12 USD.....$4 for the TPA3116D and the rest for a 24V switching power supply. I figure the noise from the cheap SMPS is not of concern in a sub. It does sound powerful indeed...better than 3 paralleled LM3886 circuit it replaced. Imagine that 70W RMS Class D for less than $20 all in and it is eco friendly. Interesting times.
I am also using a TPA3116D2 Class D chip amp for my subwoofer. Total cost of $12 USD.....$4 for the TPA3116D and the rest for a 24V switching power supply. I figure the noise from the cheap SMPS is not of concern in a sub. It does sound powerful indeed...better than 3 paralleled LM3886 circuit it replaced. Imagine that 70W RMS Class D for less than $20 all in and it is eco friendly. Interesting times.
Mikett,
That is exactly the wrong thing to do. The signal lines to the amplifiers often carry signals in the magnetic phono cartridge levels. Beside the phono, they are the most critical signal leads in your entire system. For speakers, connection resistance exceeds the bulk resistance often times. You're doing things backwards. This advice comes from people who do not understand things from a systems point of view.
Your amplifier output is the most robust signal in your entire sound system. To shorten it at the expense of other signals makes zero sense. Think about this before you do anything. Don't talk to people, just reason it out.
-Chris
That is exactly the wrong thing to do. The signal lines to the amplifiers often carry signals in the magnetic phono cartridge levels. Beside the phono, they are the most critical signal leads in your entire system. For speakers, connection resistance exceeds the bulk resistance often times. You're doing things backwards. This advice comes from people who do not understand things from a systems point of view.
Your amplifier output is the most robust signal in your entire sound system. To shorten it at the expense of other signals makes zero sense. Think about this before you do anything. Don't talk to people, just reason it out.
-Chris
Yes, you have a point. This is borne out by how this chip and tiny amp actually sounds. It is utterly transparent with just a touch of hardness at times but this could be the recording itself. It sounds like there is nothing in between. This is making me a convert to extremely short and tiny circuits....correlates to your advice about keeping interconnects short and speaker cables long.
Would the effects of the long interconnect relative to speaker wires be relative to their respective impedances? For example in this amp the input impedance is at 30K. If the cables are shielded and they are running only about 6 feet. Should I expect any substantial noise if they are driven by a source resistance of 100R.
I connected the amp to the reg with very short wires and they will get shorter when I literally put them next to each other as the next step.
The other thing that is interesting is that it is a bridged amp, something that many claim sound better. There could be something to that.
As it is, the sound is so nuanced. I did not believe it. The bass articulation in the midbass is excellent. All this with the cheap and possibly fake components. It needs a slight tiny touch of sweetness but that depends on the track.
It's for experimenting and having fun during covid. We'll see.
Would the effects of the long interconnect relative to speaker wires be relative to their respective impedances? For example in this amp the input impedance is at 30K. If the cables are shielded and they are running only about 6 feet. Should I expect any substantial noise if they are driven by a source resistance of 100R.
I connected the amp to the reg with very short wires and they will get shorter when I literally put them next to each other as the next step.
The other thing that is interesting is that it is a bridged amp, something that many claim sound better. There could be something to that.
As it is, the sound is so nuanced. I did not believe it. The bass articulation in the midbass is excellent. All this with the cheap and possibly fake components. It needs a slight tiny touch of sweetness but that depends on the track.
It's for experimenting and having fun during covid. We'll see.
Hi Mikett,
For signal cables, the source impedance plays a large role, so 100R is pretty good. But don't forget that you're driving cable capacitance as well as the input capacitance of the amplifier (often 100 pF or higher). Then you have to realize that shielded cable is often not 100%, 90% coverage is common. So you may pick up outside noise or high frequency impulse noise intermittently.
With over 40 years of audio sound system experience, my system connects with short double shielded signal cables, and the speakers are on the ends of about 45' of wire each, so a 90' round trip on 14 ga wire. They are 4R speakers. No problems with damping or any other issues. While you can't use network cable to connect your speakers, I think that, after testing several different specialty wire designs over the years, the importance of massive wire for speakers is overblown. I'm told the system sounds way better than it should for the money invested, and it wasn't a cheap system by any means.
So as long as you relax and use that grey stuff between your ears, you can create quite a good system without paying for the moon. In your case, maybe if we have a look at the schematic and your layout at some point in time, you can improve the sound quality by spending the money only where it makes a difference.
-Chris
For signal cables, the source impedance plays a large role, so 100R is pretty good. But don't forget that you're driving cable capacitance as well as the input capacitance of the amplifier (often 100 pF or higher). Then you have to realize that shielded cable is often not 100%, 90% coverage is common. So you may pick up outside noise or high frequency impulse noise intermittently.
With over 40 years of audio sound system experience, my system connects with short double shielded signal cables, and the speakers are on the ends of about 45' of wire each, so a 90' round trip on 14 ga wire. They are 4R speakers. No problems with damping or any other issues. While you can't use network cable to connect your speakers, I think that, after testing several different specialty wire designs over the years, the importance of massive wire for speakers is overblown. I'm told the system sounds way better than it should for the money invested, and it wasn't a cheap system by any means.
So as long as you relax and use that grey stuff between your ears, you can create quite a good system without paying for the moon. In your case, maybe if we have a look at the schematic and your layout at some point in time, you can improve the sound quality by spending the money only where it makes a difference.
-Chris
That's a very nice offer man.
I've been knocking my builds out by hand. My 10" Drill Press is junk and I can do it better with my hand drill.
What I really would like to know is where around the GTA you can do still like a front panel with CNC instead of ordering from FPE or something.
There used to be some shops around Toronto. I used a waterjet company at Dufferin and 407. May be gone by now. I used Front Panel Express tool to lay it out. Printed it to check layout, then exported to a standard file. Emailed to various cnc shops here to get prices. It turned out really nice at a fraction of cost for FPE. And you can pick it up to avoid shipping which is crazy expensive from California.
Walter
Walter
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Really beautiful work Walter! Do you have more pictures posted and more info on it? I think you said the design didn't require OPTs. Is it a push-pull or single ended/parallel design?
Hope everyone is is healthy and safe! Be well and hopefully we'll see each other again by summer.
Stephen
Hope everyone is is healthy and safe! Be well and hopefully we'll see each other again by summer.
Stephen
Thanks Stephen
They are a pair of 110W OTL class AB monoblocks. They are 95% design by Bruce Rozenblit Transcendent Sound. I changed the small signal tubes to 6n2p and 6n6p. I also beefed up the power supplies with larger transformers and CLC filters to result in a stiffer quieter system. They sound amazing to my ear, and the tubes are still comparatively cost effective.
When I built them several years ago, I did a few blog entries to capture my thoughts real time as I learned how to build these things. There are a few pics of the process and the end result. It was my first real build effort. They remain at the heart of my main system, and are kind of my pride and joy. diyAudio - wlowes
I made them big to avoid problems. Here is a picture of the pair with a cd player on my pool table for scale.
They are a pair of 110W OTL class AB monoblocks. They are 95% design by Bruce Rozenblit Transcendent Sound. I changed the small signal tubes to 6n2p and 6n6p. I also beefed up the power supplies with larger transformers and CLC filters to result in a stiffer quieter system. They sound amazing to my ear, and the tubes are still comparatively cost effective.
When I built them several years ago, I did a few blog entries to capture my thoughts real time as I learned how to build these things. There are a few pics of the process and the end result. It was my first real build effort. They remain at the heart of my main system, and are kind of my pride and joy. diyAudio - wlowes
I made them big to avoid problems. Here is a picture of the pair with a cd player on my pool table for scale.
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My isolation project
I don't mean isolation transformer. I mean what I am doing while I'm locked away from the world trying to avoid the pandemic.
Very slowly I am finally getting speaker cabinets built. I'll post pics in a few weeks of the finished product. I am building my take on the Lampizator P17. Basically an 18" pro driver in a large open backed box for the bass, and a 10" Coral coax full range in a small open baffle for everything above 120hz. The small open baffle is 12x13". By sitting on top of the big box I avoid the big baffle problems and it can be moved to be perfectly time aligned with the bass.
The baffles are 1.5" thick black walnut to match the rest of the system. Boxes are finished and baffles were done by a pro butcher block builder. Should get delivery of baffles next week. Then assembly, finishing followed by audio nirvana.
pics of work in progress
I don't mean isolation transformer. I mean what I am doing while I'm locked away from the world trying to avoid the pandemic.
Very slowly I am finally getting speaker cabinets built. I'll post pics in a few weeks of the finished product. I am building my take on the Lampizator P17. Basically an 18" pro driver in a large open backed box for the bass, and a 10" Coral coax full range in a small open baffle for everything above 120hz. The small open baffle is 12x13". By sitting on top of the big box I avoid the big baffle problems and it can be moved to be perfectly time aligned with the bass.
The baffles are 1.5" thick black walnut to match the rest of the system. Boxes are finished and baffles were done by a pro butcher block builder. Should get delivery of baffles next week. Then assembly, finishing followed by audio nirvana.
pics of work in progress
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