Hello all, first some background. In 1993, while in high school, I started my first job in KFC. With all that money that I never had before, I really wanted to first buy a really nice music system. I had already started DJ'ing and also performed Shabba Ranks lines on the mic. I was so ready to move on from my DJ rig in my bedroom. I started reading all the reviews in AU hi-fi mag and taking handfuls of Greensleeves sampler CDs to all the high-end shops around Sydney. Nothing really seemed to do the music justice. I used to have a portable with CD and cable to stick the headphone out to my PA. I took this to an op shop that carried a lot of secondhand electronics. There magic happened, a wooded cabinet for $10 sounded better than anything on York Street, Sydney. It had these huge speakers built in and a record player! And line in!! And mic in!!!
Needless to say, I saved a lot of money and bought new decks and a mixer kit from Jaycar 😀
A friend and I carried it home all of 600m, which seemed like 6000km. This thing was heavy
Things went south for me from there. Firstly, abusing new-found freedom in the anonymity of a city of 3 million, dropping out of year 12 in high school, getting married very early and eventually into self-employment as a fishing rod manufacturer and design consultant. Fifteen years later I followed my conscience and got out of the blood sport industry and bad marriage and took up taxi. Today I am with the person that I am right for and with a small family but toeing 50 and in semi retirement at the end of healing from the past life
Every day since 1993 I think about that old system and how good it sounded. In time, I learned about the nature of tubes and why that thing did what it did, and still don't know why I have never revisited that. I have fond myself longing for a small portable that sounds that good and something my wife and I can down time with. Or I can sit at sunset on the steps of the sailing club at the beach and enjoy some dub and even play my bass along with
I have the preamp already for plugging the bass into any hi-fi, so the instrument side of this portable is a separate issue already resolved and can apply to this or any other system with a line in
While fitting this to a new bass amp two years ago, I thought about how cool would that have been to plug into the old system that had that glinty golden sheen on the bass of Robbie Shakespeare and Aston Barrett. Things get smaller over time, so why not the old system. After pondering this for the last two years, I think I should dive in head first and build and enjoy this thing instead of just thinking about it
Please take it in the spirit intended and coming from someone fairly uneducated
The thread discussing the LF driver side of things
The thread discussing the FR stereo drivers
I have compiled a good parts bin
Visaton waterproof FR drivers
Various 6.5" subs and one JBL BB3 replacement bass driver
Dayton reference alloy PRs, no name PRs
DS18 ZXI-354 FR drivers
7" SBA or Wavecor sub, can't tell
2.75" SBA or Wavecor FRs, can't tell
DC24V 2.1 poweramp with DSP TPA3116D2 based with 50w+50w+100w at 4R+4R+2R
Just the DSP
Just the poweramps in separate stereo and mono boards including TPA3116, TPA3118, PAM8403, PAM8610
DC12V to DC24V 15 amp stepper
DC12V to tube power stepper
Various 12v batteries and chargers
Creality 6 Max printer
Desktop CNC router + laser module
Mini industrial table saw
Comprehensive hand and power tools
Calibrated mic
Audio interface
Various software
6SN7 tube preamp PCBs and tubes
6SN7 tube headphone amp PCB and tubes
5670 PCBs and tubes
Lots of passives
ECC83 tubes
The tools are all for my main interest being bass amps, bass instruments and WIG vessels and the audio components are for trying to achieve the portable through trial and error. During the course of discussion re the FR drivers, it seemed like the starting point of the project, the headphone amp was a bit under equipped, so I am adding an EL34 SET kit into the parts bin including very well specified output transformers as well as Psvane red EL34s. Also adding an analog voltage divider network and analog sub controller to the mix. And a pair of 1.75" JBL long stroke type 15wrms FR drivers
Thinking about adding a very well-made TPA3221 stereo board from NVarcher into the mix too for the sub to run straight from 12v instead of lesser chips already on hand
I feel that I have sufficient mix of parts to trail and error with to end up with a very small version of the HMV unit that is perfect as a low output personal music system for two. Will introduce the model for the max allowed dimensions for the chassis as I work various things out
Needless to say, I saved a lot of money and bought new decks and a mixer kit from Jaycar 😀
A friend and I carried it home all of 600m, which seemed like 6000km. This thing was heavy
Things went south for me from there. Firstly, abusing new-found freedom in the anonymity of a city of 3 million, dropping out of year 12 in high school, getting married very early and eventually into self-employment as a fishing rod manufacturer and design consultant. Fifteen years later I followed my conscience and got out of the blood sport industry and bad marriage and took up taxi. Today I am with the person that I am right for and with a small family but toeing 50 and in semi retirement at the end of healing from the past life
Every day since 1993 I think about that old system and how good it sounded. In time, I learned about the nature of tubes and why that thing did what it did, and still don't know why I have never revisited that. I have fond myself longing for a small portable that sounds that good and something my wife and I can down time with. Or I can sit at sunset on the steps of the sailing club at the beach and enjoy some dub and even play my bass along with
I have the preamp already for plugging the bass into any hi-fi, so the instrument side of this portable is a separate issue already resolved and can apply to this or any other system with a line in
While fitting this to a new bass amp two years ago, I thought about how cool would that have been to plug into the old system that had that glinty golden sheen on the bass of Robbie Shakespeare and Aston Barrett. Things get smaller over time, so why not the old system. After pondering this for the last two years, I think I should dive in head first and build and enjoy this thing instead of just thinking about it
Please take it in the spirit intended and coming from someone fairly uneducated
The thread discussing the LF driver side of things
The thread discussing the FR stereo drivers
I have compiled a good parts bin
Visaton waterproof FR drivers
Various 6.5" subs and one JBL BB3 replacement bass driver
Dayton reference alloy PRs, no name PRs
DS18 ZXI-354 FR drivers
7" SBA or Wavecor sub, can't tell
2.75" SBA or Wavecor FRs, can't tell
DC24V 2.1 poweramp with DSP TPA3116D2 based with 50w+50w+100w at 4R+4R+2R
Just the DSP
Just the poweramps in separate stereo and mono boards including TPA3116, TPA3118, PAM8403, PAM8610
DC12V to DC24V 15 amp stepper
DC12V to tube power stepper
Various 12v batteries and chargers
Creality 6 Max printer
Desktop CNC router + laser module
Mini industrial table saw
Comprehensive hand and power tools
Calibrated mic
Audio interface
Various software
6SN7 tube preamp PCBs and tubes
6SN7 tube headphone amp PCB and tubes
5670 PCBs and tubes
Lots of passives
ECC83 tubes
The tools are all for my main interest being bass amps, bass instruments and WIG vessels and the audio components are for trying to achieve the portable through trial and error. During the course of discussion re the FR drivers, it seemed like the starting point of the project, the headphone amp was a bit under equipped, so I am adding an EL34 SET kit into the parts bin including very well specified output transformers as well as Psvane red EL34s. Also adding an analog voltage divider network and analog sub controller to the mix. And a pair of 1.75" JBL long stroke type 15wrms FR drivers
Thinking about adding a very well-made TPA3221 stereo board from NVarcher into the mix too for the sub to run straight from 12v instead of lesser chips already on hand
I feel that I have sufficient mix of parts to trail and error with to end up with a very small version of the HMV unit that is perfect as a low output personal music system for two. Will introduce the model for the max allowed dimensions for the chassis as I work various things out
From my parts bin, I can see three starting options for tube
Option 1:
The 6N5P headphone amp. The item has been discontinued, but I saved the schematic
Option 2:
6N5P preamps
I have two of these and the tubes and PSU
Option 3:
EL34 poweramp
I ordered the built board and the output transformers in that listing and the following valves. I already have the PSU
PSVANE Tube EL34C Original Factory Matched Pair
Fire Crew PSVANE Vacuum Tube ECC83
Now to figure out the DC12v PSU for benchmarking. I have a new 130 amp hour gel cell that can run steady for a long time but will now spend some time looking at a lithium option for at least 6hrs use at half volume based on option three for benchmarking
Option 1:
The 6N5P headphone amp. The item has been discontinued, but I saved the schematic
Option 2:
6N5P preamps
I have two of these and the tubes and PSU
Option 3:
EL34 poweramp
I ordered the built board and the output transformers in that listing and the following valves. I already have the PSU
PSVANE Tube EL34C Original Factory Matched Pair
Fire Crew PSVANE Vacuum Tube ECC83
Now to figure out the DC12v PSU for benchmarking. I have a new 130 amp hour gel cell that can run steady for a long time but will now spend some time looking at a lithium option for at least 6hrs use at half volume based on option three for benchmarking
NVarcher TP3211
This just presents itself as well-built, unlike most of the lesser chip boards. One is winging its way over right now. I like the idea of this one as the Class D stage for the LF driver applied at the output transformer on the EL34 amp using a voltage divider made up with a couple of resistors
I think I can work out the needed juice for this board, but not sure on the Class A EL34 amps consumption
The PSU for tube
This just presents itself as well-built, unlike most of the lesser chip boards. One is winging its way over right now. I like the idea of this one as the Class D stage for the LF driver applied at the output transformer on the EL34 amp using a voltage divider made up with a couple of resistors
I think I can work out the needed juice for this board, but not sure on the Class A EL34 amps consumption
The PSU for tube
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A test to see if I am getting this working out the power requirements types of things. Took a bit of work to find out which are the fake listings and things. The best that I can work out is that the following battery is legit and a good choice as a LiFePO4 type unit. Hopefully the 10a continuous and 30a 3sec burst ratings are ample for the average half way volume. Not sure about the charge life, but I think it just might be dependable enough to last most outings. It's a bit on the large side, though. Not worried about the weight as the portable will have a mount on the pram
Would really appreciate some advice on this from a knowing type fellow
The listing mentions a free upgrade to 10Ah
12V 7Ah LiFePO4
Would really appreciate some advice on this from a knowing type fellow
The listing mentions a free upgrade to 10Ah
12V 7Ah LiFePO4
https://www.valvewizard.co.uk/Common_Gain_Stage.pdf
Trying to find a good easy to follow guide like this with Hi-fi rather than instrument bias
Trying to find a good easy to follow guide like this with Hi-fi rather than instrument bias
Just my luck. As soon as I had decided to dive head first into this, I ran head first into two weeks of national holiday in PRC. A number of vendors, including the EL34 amp guys, messaged requesting that I cancel the order from my end as they won't be able to ship until Valentines
The Fire Crews and TPA3221 did get shipped, and the number one contender for the LF driver for the portable arrived a week early via ship from Big Jeff's. The vendor who sent the tubes inquired if I needed anything else for the EL34s., I mentioned the situation with the shop that had the amp. The tube guy turned out to be an enthusiast and sent regrets that he didn't carry the amp kits and video of his personal EL34 amp that he built from a kit. His service and attitude was exemplary as he had first sent a request asking for me to also cancel but soon after sending the message had recalled it and made sure that it was in the last pickup from the courier
The ZR6.4D cone is well doped and the suspension feels almost as stiff as the first W7. It's also the 2nd largest 6.5" in my personal experience. No rush on the EL34 as I do have the headphone amp and 6N5P and 5670 preamps to tinker with. An idea does occur to use these and read up on modding to a bass and treble tone control to drive the class d amps
The Fire Crews and TPA3221 did get shipped, and the number one contender for the LF driver for the portable arrived a week early via ship from Big Jeff's. The vendor who sent the tubes inquired if I needed anything else for the EL34s., I mentioned the situation with the shop that had the amp. The tube guy turned out to be an enthusiast and sent regrets that he didn't carry the amp kits and video of his personal EL34 amp that he built from a kit. His service and attitude was exemplary as he had first sent a request asking for me to also cancel but soon after sending the message had recalled it and made sure that it was in the last pickup from the courier
The ZR6.4D cone is well doped and the suspension feels almost as stiff as the first W7. It's also the 2nd largest 6.5" in my personal experience. No rush on the EL34 as I do have the headphone amp and 6N5P and 5670 preamps to tinker with. An idea does occur to use these and read up on modding to a bass and treble tone control to drive the class d amps
Here is an interesting one. The JBL BB3 look alike LF driver failed to clear customs. Do they watch for clones and things?
The Visaton FR 8 WP drivers arrived yesterday and what a disappointment. Flimsy plastic all in one basket, mag cover and grill. One of the drivers rattles so an unattached magnet. These are going back to mouser
Mouser were awesome and approved the return without drama. Hope the JBL style drivers prove better built
A bunch of items arrived today to trail and error for this project. Mostly micro drivers and the racer sub as well as the battery. Is there a way to tell if it's a real LiFePO4 without opening it up?
Thanks. I'll take it to the local Jaycar to get some plugs for it and ask an acquaintance there about this
Hi-IC Store finally got back with a message that they have updated inventory, and I placed an order for the EL34 SE amp kit and a pair of output transformers. So now the project has 10w per stereo channel to play with. The PSVANE Hot Chilli tubes have already arrived and so has an interesting pair of 6.5" full range drivers with Tangy bra type bullet phase plugs. No specs so hoping they might go well in the small volume with a PR behind each. I'll get in some PR units that are really low compliance with only the rubber surround and no basket or spider
I now have about half a cubic meter of components for trail and error to come up with something that really nails all the items on the SOR
I really want to add a USB interface to this portable, any ideas guys? It must be IOS compatible for use with an iPad and iPhone, as well as PC and MAC. Would really help if this same internal interface can be used with a windows laptop and ARTA
I now have about half a cubic meter of components for trail and error to come up with something that really nails all the items on the SOR
I really want to add a USB interface to this portable, any ideas guys? It must be IOS compatible for use with an iPad and iPhone, as well as PC and MAC. Would really help if this same internal interface can be used with a windows laptop and ARTA