DIY Audio Projects Forum
 NEW  Matt presents bias and operation data for the 6V6 tube in SE operation - 6V6 Single-Ended (SE) Ultra Linear (UL) Bias Optimization.

DIY Audio Projects Forum

Welcome to the DIY Audio Projects Message Forum. Use these forums to discuss Hi-Fi audio and to share your DIY Audio Projects. Registration is free and required to post messages and view the file attachments. Registration will only take a minute and registered users do not see any advertisements. After you have completed the online registration process, check your email (including spam/junk folder) for the verification email to activate your account. New members are under moderation - so your posts will not be visible until approved by a moderator. See the Read Me 1st, Forum RULES and Forum FAQ to get started on the forum.

It is currently 21 Aug 2018, 05:13

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 5 posts ] 
Author Message
PostPosted: 08 May 2014, 01:53 
Offline

Joined: 08 May 2014, 01:15
Posts: 2
Hey guys, have been getting a lot of tips reading these forums but have hit a wall at speaker selection so decided to join up and just ask. I noticed there was another boombox thread posted just now however was hoping to get some advice more specific for my application.

What I have is a smallish relatively lightweight box (it's a sharp M9935k). Currently I've modified it by removing the tuner and replacing with a raspberry pi, gave it an i2s dac and hooked that all up to stock power / amp / switches etc.. and feeding it UPNP from either my network or ad hoc with phone when taking it to the streets. Whole thing draws 350 odd ma, and has run off 6 D cell for an acceptable amount of time (they're not flat yet) It all works pretty well, but the sound sucks. As the original box itself only cost me a few bucks I've decided to see what else I can get out of it.

I've planned out a simple mod for 2 more cells to get 12v and pulled the trigger on 2x amp6 basic which seemed as though they might suit. What's got me stuck though is speakers. Originals are 6.5" with mounting holes at about 7", 90degree spacing - depth is only about 2". Max mounting depth available would be around 4" going right to the back of the box. Total box volume is about 0.47ft3 and is vented at the back. Any suggestions on what may work well, or work at all?

Thanks guys


Top
 Profile  
 
PostPosted: 11 May 2014, 21:11 
Offline
Editor
User avatar

Joined: 28 May 2008, 21:53
Posts: 4559
Location: Winnipeg, CANADA
Hi and welcome to the forum. I like the raspberrypi implementation. I noticed the other day there is an audiophile distro available. Are the original speaker drivers a paper cone fullrange?

Cheers

_________________
[ DIY Mains AC Power Cable Cord ] - [ Gobo LM1875 Amp Kit ] - [ Tang Band D4-1 Horn Speaker Kit ] - [ Monoblock Push-Pull KT88 Tube Amp Kit ]


Top
 Profile  
 
PostPosted: 12 May 2014, 02:19 
Offline

Joined: 08 May 2014, 01:15
Posts: 2
Thanks, yes there is 'volumio' which I've played around with a little and looks like it's coming along nicely. Right now for this project I'm using raspbian and gmrender-resurrect as I wanted upnp support. Just picked up a model A pi and taken a couple of quick readings which show significantly less draw than the model B, good news for batteries.

Original speakers in question are paper cone and possibly mid range - I say possibly because the box is stickered as '4 speaker' and there are what appear to be separate tweeters, I havn't bothered testing as I can't get those out without a fair bit of destruction. Was planning on using a full set range as the replacements if possible


Top
 Profile  
 
PostPosted: 19 May 2014, 10:35 
Offline
Editor
User avatar

Joined: 28 May 2008, 21:53
Posts: 4559
Location: Winnipeg, CANADA
Probably a two way, the lower unit run fullrange and just a cap on the tweeter. Can you post a photo. The box is probally not work choosing anything but some inexpexnsive drivers. This would be more to experiment and see what you can come up with. It probally won't be too hard to improve the factory speakers somewhat, but count on large improvements.

Cheers

_________________
[ DIY Mains AC Power Cable Cord ] - [ Gobo LM1875 Amp Kit ] - [ Tang Band D4-1 Horn Speaker Kit ] - [ Monoblock Push-Pull KT88 Tube Amp Kit ]


Top
 Profile  
 
PostPosted: 12 Jun 2016, 21:16 
Offline

Joined: 12 Jun 2016, 21:10
Posts: 1
"...What I have is a smallish relatively lightweight box (it's a sharp M9935k). Currently I've modified it by removing the tuner and replacing with a raspberry pi,..."

I am trying to intergate a Pi Zero into my m9935K. Where in the audio path did you connect your pi?


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
DIY Tube Projects :: DIY Tube Amp Kits :: DIY Speaker Projects :: DIY Solid State Projects :: DIY IC / Op-amp Projects :: DIY Phono Projects :: DIY Cable Projects :: Hi-Fi Audio Schematics
© diyAudioProjects.com - Terms of Service - Privacy Policy