I am definitely inspired by this site.
Many things popping into my head.
-Rolling my own IC per this link:
DIY Silver Interconnects
Starting with low cost parts (copper, plain wire) first and then moving up. I envision very large diameter Teflon pipe running straight lengths of 0.50m to equipment designed to accept 'right angle' direct straight IC.
-Rolling own speaker cable as well.
Doing this also in a big way with very large diametre PTFE that would require straight runs and source and amp designs to accommodate these unbend-able runs.
Many questions:
-Driver terminals are too small for the wire I wish to use. Many tweeters have tiny terminal holes and I want to use 16AWG soldering into the them.
Are there terminal extenders for drivers? That is, another terminal that you insert inside the smaller one, solder that joint, and the new terminal has a big fat hole to accept very large diameter AWG? I am sure you all know that the standard issue wire is 24AWG at best. A few strands of brittle copper.
-I have searched several sites but I cannot find high quality MINI plugs to roll my own. I want several of these due to the fact that I will have many small tube amps for a while and wish to try them out as preamps and they almost always have only a mini output. I want to roll my own mini plug to 2 RCA.
Also wish to roll my own one mini plug to 4 RCA for mono amp input.
-Please do not flame or scoff, it's been since 1977 since I worked on stuff like this - but is there any obvious reason why I cannot purchase a pair of identical PA mono amps and using a pair of "one RCA male to 2 RCA female" to create input to a pair of slap dash monoblocks?
Is there something I am missing wrt load, impedance, grounding, phase, source issues, amp mismatch or such that this would not work?
Many things popping into my head.
-Rolling my own IC per this link:
DIY Silver Interconnects
Starting with low cost parts (copper, plain wire) first and then moving up. I envision very large diameter Teflon pipe running straight lengths of 0.50m to equipment designed to accept 'right angle' direct straight IC.
-Rolling own speaker cable as well.
Doing this also in a big way with very large diametre PTFE that would require straight runs and source and amp designs to accommodate these unbend-able runs.
Many questions:
-Driver terminals are too small for the wire I wish to use. Many tweeters have tiny terminal holes and I want to use 16AWG soldering into the them.
Are there terminal extenders for drivers? That is, another terminal that you insert inside the smaller one, solder that joint, and the new terminal has a big fat hole to accept very large diameter AWG? I am sure you all know that the standard issue wire is 24AWG at best. A few strands of brittle copper.
-I have searched several sites but I cannot find high quality MINI plugs to roll my own. I want several of these due to the fact that I will have many small tube amps for a while and wish to try them out as preamps and they almost always have only a mini output. I want to roll my own mini plug to 2 RCA.
Also wish to roll my own one mini plug to 4 RCA for mono amp input.
-Please do not flame or scoff, it's been since 1977 since I worked on stuff like this - but is there any obvious reason why I cannot purchase a pair of identical PA mono amps and using a pair of "one RCA male to 2 RCA female" to create input to a pair of slap dash monoblocks?
Is there something I am missing wrt load, impedance, grounding, phase, source issues, amp mismatch or such that this would not work?
As long as you go low impedance into high impedance, and the sensitivities are within an order of magnitude you should be able to find and eliminate polarity and grounding problems (well, assuming the amps are reasonably well designed. It's always possible to make unusable gear, but the odds are in your favour).
Unfortunately, driving two outputs of a stereo preamp (or ipod or whatever) connected together to create a mono signal, that's loz-loz, = ought not to do it. Ought to incorporate resistors into RCA jacks so each output sees a reasonable impedance, otherwise 0 ohm drive from one op amp is going to see 0 ohm of other output as a short circuit, and distort. Eetzy little resistors fit into plugs fine, but connection is fragile relative to soldered properly onto terminals, so be very careful with cable clamps.
Neutrik do some quite good 3.5mm stereo jacks, but they're big. ( Um. I thought when you said "MINI plugs") this was what you were referring to; but given "small tube amps almost always have" I'm now less certain.)Which means there are quite a lot of aparatuses into which they simply will not plug. I buy moulded, and clip the connectors off. Certainly, it's not the worlds greatest cable, but 3.5 mm jacks are such lousy connectors…
Why the insistence on mono? Not that mono's bad, or anything, but if you are going to pick up a couple of amps anyway it would simplify your project to wire them stereo and just put the speakers close together (waits for thunderbolts from the phase angle people). Unless you're biamping, or something, in which case it's a whole different kettle of fish. If we had a better idea of your final aims (apart from making noise) we – or at least I – would be able to give much better informed answers.
There are crimp on terminals - for automobile wiring, I believe – that crimp onto decent thickness cable and bring out quite a narrow spike which can often be persuaded into speaker terminals. I don't like them much; the terminals tend to come unscrewed from them faster than a multi-stranded cable, but they are a potential solution.
Unfortunately, driving two outputs of a stereo preamp (or ipod or whatever) connected together to create a mono signal, that's loz-loz, = ought not to do it. Ought to incorporate resistors into RCA jacks so each output sees a reasonable impedance, otherwise 0 ohm drive from one op amp is going to see 0 ohm of other output as a short circuit, and distort. Eetzy little resistors fit into plugs fine, but connection is fragile relative to soldered properly onto terminals, so be very careful with cable clamps.
Neutrik do some quite good 3.5mm stereo jacks, but they're big. ( Um. I thought when you said "MINI plugs") this was what you were referring to; but given "small tube amps almost always have" I'm now less certain.)Which means there are quite a lot of aparatuses into which they simply will not plug. I buy moulded, and clip the connectors off. Certainly, it's not the worlds greatest cable, but 3.5 mm jacks are such lousy connectors…
Why the insistence on mono? Not that mono's bad, or anything, but if you are going to pick up a couple of amps anyway it would simplify your project to wire them stereo and just put the speakers close together (waits for thunderbolts from the phase angle people). Unless you're biamping, or something, in which case it's a whole different kettle of fish. If we had a better idea of your final aims (apart from making noise) we – or at least I – would be able to give much better informed answers.
There are crimp on terminals - for automobile wiring, I believe – that crimp onto decent thickness cable and bring out quite a narrow spike which can often be persuaded into speaker terminals. I don't like them much; the terminals tend to come unscrewed from them faster than a multi-stranded cable, but they are a potential solution.
Mini plug: 1/8" stereo (TRS) mini plug. 3.5mm plug as you refer to it.
The idea is to SPLIT the output of a preamp/iPod/whatever using a Y-connector. So the R-output is split to a pair of RCA male plugs that then connect to one mono PA amp, and the L-Output is split to a pair of RCA male plugs connected to the other.
These are restaurant/public address 50W amps with one 4-16 ohn post pair and one 100V post pair. They do not have L-R speaker posts just one common bus for all channels. These amps have a built in USB that picks the left channel and then plays that, or does an odd phase thing with the USB input on the way to the gain stages.
The source would not be shorted, the input of each amp would be 'seeing' the same signal at both channel inputs for what I have available. Clearly building my own single jack input monos are a ways down the road.
I simply want to use this tester amp I picked up to toss together a cheap monoblock setup as I scale up the learning curve. I am making lots of beginner mistakes and want to make them on disposable gear, not a pair of $5,000 mono blocks and some Lowther drivers.
The idea is to SPLIT the output of a preamp/iPod/whatever using a Y-connector. So the R-output is split to a pair of RCA male plugs that then connect to one mono PA amp, and the L-Output is split to a pair of RCA male plugs connected to the other.
These are restaurant/public address 50W amps with one 4-16 ohn post pair and one 100V post pair. They do not have L-R speaker posts just one common bus for all channels. These amps have a built in USB that picks the left channel and then plays that, or does an odd phase thing with the USB input on the way to the gain stages.
The source would not be shorted, the input of each amp would be 'seeing' the same signal at both channel inputs for what I have available. Clearly building my own single jack input monos are a ways down the road.
I simply want to use this tester amp I picked up to toss together a cheap monoblock setup as I scale up the learning curve. I am making lots of beginner mistakes and want to make them on disposable gear, not a pair of $5,000 mono blocks and some Lowther drivers.
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Oh, splitting should work fine; no-one uses 600Ω-600Ω matching for anything less than a few kilometres of wire any more, and 2k-50k gives you a lot of fanout potential. Shouldn't give any problems whatsoever (apart from the usual grounding and cable routing, but that's true of anyone who works unbalanced). Though, looking at your wiring description, if the amp is mono, do you get any advantage from running into the two inputs; they're mixed together inside, anyway (a few dBs of extra gain, but I'm sure you could make that up otherwise, and reduce the number of connectors you're running through; always an improvement in reliability).
It's only blending where you hit the impedance mismatch, and even then, as mini jack outs are designed to have the potential for headphone use, they've often got series resistors allowing you to get away with it (not elegant, though).
Is the PTFE wire because you've got some? Because you're planning to work in a volcano to test out some asbestos cone loudspeakers?
It's horrible stuff, nasty to strip, only advantage being it doesn't melt back when you solder to it.
All right, I'll bite – tube amps? And USB interface, and mini jacks? I take it "tube" in this case does not mean 'vacuum state'; did you roll your own and get a cylindrical preamp?
It's only blending where you hit the impedance mismatch, and even then, as mini jack outs are designed to have the potential for headphone use, they've often got series resistors allowing you to get away with it (not elegant, though).
Is the PTFE wire because you've got some? Because you're planning to work in a volcano to test out some asbestos cone loudspeakers?
It's horrible stuff, nasty to strip, only advantage being it doesn't melt back when you solder to it.All right, I'll bite – tube amps? And USB interface, and mini jacks? I take it "tube" in this case does not mean 'vacuum state'; did you roll your own and get a cylindrical preamp?
Thanks for the single RCA jack tip. Simple is better. A bare input just bothers me on a purist level.
PTFE is not the wire, it is going to be my IC's inner core. Wire would be 16AWG copper strand helix around that. This amp is a PA 110 constant voltage amp with taps to the transformer to provide 4Ω -16Ω at one pair of mono posts. My speakers wire and xovers measure at the wire closest to the amp at 5.5Ω each so that is no issue. Since I already have one of these amps, ordering another is easy and I can have a cheap mono block setup whilst I learn and build and mod.
Still looking for a simple USB input to the amp solution as this system is now in the living room and no longer at my PC workstation next to my workbench and I have no source for the amp that can use my reclockers and ODAC's from a USB output and my music collection.
Tube amps because I am in China and there are many Chinese made low end to satisfy my curiosity - 6J1's, 6N11's and such, palm-sized amps, very tiny - and I have many headphones and use those with these various small amps. Those amps are headfi amps and usually have a 3.5mm mini jack input and/or audio output as well as RCA audio R-L output. So I am trying to get these 500mw tube amps setup as a preamp to this nascent mono-block setup.
No volcanoes nearby, however...
PTFE is not the wire, it is going to be my IC's inner core. Wire would be 16AWG copper strand helix around that. This amp is a PA 110 constant voltage amp with taps to the transformer to provide 4Ω -16Ω at one pair of mono posts. My speakers wire and xovers measure at the wire closest to the amp at 5.5Ω each so that is no issue. Since I already have one of these amps, ordering another is easy and I can have a cheap mono block setup whilst I learn and build and mod.
Still looking for a simple USB input to the amp solution as this system is now in the living room and no longer at my PC workstation next to my workbench and I have no source for the amp that can use my reclockers and ODAC's from a USB output and my music collection.
Tube amps because I am in China and there are many Chinese made low end to satisfy my curiosity - 6J1's, 6N11's and such, palm-sized amps, very tiny - and I have many headphones and use those with these various small amps. Those amps are headfi amps and usually have a 3.5mm mini jack input and/or audio output as well as RCA audio R-L output. So I am trying to get these 500mw tube amps setup as a preamp to this nascent mono-block setup.
No volcanoes nearby, however...
It's best to clearly state (for yourself) what you want to accomplish in technical terms. Once you do that you can research each issue and find out what others have done and what the pros and cons of each method are. It's good to try and take advantage of what your local area has to offer, cheap tube amps, etc. Right now it sounds like you have a bunch of ideas, some good, some snake oil, gleaned from sites/posts/threads/write-ups of possibly dubious origin!
I'm sorry about the volcano; I have been known to be less than 100% serious at times. I do try to add smilies when this happens, but sometimes forget.
I've worked with PTFE (polytetrafluoroethylene, teflon) wire for high frequency applications, so it wasn't an impossible assumption.
I've recently solved the USB problem for a friend using the Behringer Xenyx 302USB - a micro mixer with a microphone input and stereo line, tone control and bidirectional conversion USB, costing barely more than a straight converter. Powered by USB, lots of flexibility (if you know how to use it). Might be more than you want, though.
I've worked with PTFE (polytetrafluoroethylene, teflon) wire for high frequency applications, so it wasn't an impossible assumption.
I've recently solved the USB problem for a friend using the Behringer Xenyx 302USB - a micro mixer with a microphone input and stereo line, tone control and bidirectional conversion USB, costing barely more than a straight converter. Powered by USB, lots of flexibility (if you know how to use it). Might be more than you want, though.
My plan is to slowly gear up and work up the price chain, for fun. My skills are out of date and extremely rusty. It's been nearly 25 years since I was into the hobby and much has changed and lots of new tech is out there I have never heard. Since I am far removed from civilisation, building my own gear makes sense. Headphones and another forum and site are for the highest end listening with big bass and best accuracy (T1's and such), so the listening setup for speakers will be with other priorities.
Sound goals and priorities are midrange, sound-stage, verisimilitude, rhythm and clean sound. Sources will be rock but the best reproduction of that will be via Grado's, so the living room setup will be voiced to work well with acoustic, jazz, female vocals, chamber music. I like all kinds of music but a system cannot be all things to all styles. 2.0 channels, not HT. I like deep bass, but I do not want a set of 8 X 18" subs in my living room. Very loud listening volumes with ultra deep bass would be disruptive to the many nearby neighbours. So I am going for clean midrange, decent extension, sound-stage, engagement with the performance, toe tapping ability.
First:
-Finish the rebuild of the TV boxes that came with an old CRT as outboard speakers. They need new drivers in the R-hand unit, so I am upgrading all 4.
-Buy online several small headfi tube amps to go with many pairs of headphones.
-Buy online several outboard ODAC's and re-clockers and USB DAP's to feed the amps.
-Take the ODAC's and pair with the bigger amps that can power loudspeakers and move them into the living room.
-Get another constant voltage amp and use it as the other channel of a stereo mono-block. Each amp already has two amps in the chassis. so no need for 'four'.
-Get a USB source to play tunes in the living room and feed one of the headfi tube amps as a preamp stage. Perhaps even a used laptop - likely the easiest solution.
Second
-Design a full range single driver speaker with the amp in mind to match them well as a set
-Move on to the second speaker build, a full range single driver unit (4" to 8" not decided yet) in a cabinet, no crossover, good drivers - Lowther, and those.
-Hook that up to my cheap-o mono-block
-Buy (not build) a compatible tube amp to pair with the single driver speakers. Mono-block and bridgability in mind.
-Cabinetry fit and finish will be the biggest challenge
Along the way making my own speaker cables and IC's. Yesterday I upgraded the 24AWG strand to 10AWG solid core copper and even with the low rent gear I have now, this change made an audible difference. Teflon core piping, teflon tape, wrapping the sold core around it, etc.
Down the line perhaps design a tube amp SET or OTL, mono-blocks as I want a pair, but that is far in the future; to the CE's and EE's reading, I am well aware of the issues and dangers involved with HV tube circuits.
Maybe one sub-woofer but the xover is something I want to avoid as one goal is signal purity and simplicity. But it would be an easier build of a cube sub and Class D, than many other projects.
So that's the plan. Get this first build up, pair it with some PA constant voltage amps, then build the single driver full range speaker, and get an amp to go with that. Have a set of custom made speakers in most rooms of the house.
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Thanks for the great suggestion!
However, I am looking for something to plug a USB 2.0 thumbdrive into near the amp.
Thumbdrive>>[[UNKNOWN DEVICE]]>>Reclocker>>ODAC>>Preamp>>Amp>>Speakers
I do not have any use for any portable DAP such as a Nano or iPod. I simply need to take copies of my music from my PC, into the living room, and play them there.
I think that the solution I am looking for would be best met by a used laptop near the system, but I do not wish to have a computer sitting there.
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