DIY amp case help with materials and HUGE pre made cost justification !

[Fivetide]

Right – so I have just got all my parts together to make my DIY Mighty Midget Valve Amplifier






which I’m making for my Dad’s 75’th birthday,( I don't think I will get it finished on time, but I'll try) I’d listened to one at my friends who had scratch built it without the PCB you can now get. And although not the most powerful in the world the sound from his record player was awesome.(why do I rant on, this is way off subject?) Also was the size consideration as I wanted to make the case myself and I only have a limited amount of working area. But I thought just to see how much I was saving I would get a quote from front Panel Express as Peter had done all the hard work to produce the necessary files. FPE forwarded the quote onto Schaeffer AG and below is the cost .. Translated into proper money would be **£154** ! The only thing I can’t do at the moment is screen print the front panel, but I was going to etch it out and then hand fill it with paint. Now I might be blowing smoke up my own arse here but it doesn’t look that complicated to me. I’ve done a couple of Objective headphone amp front and rears using the already created FPE files and it took me about 20 minutes for the first one and 2 minutes for the second. If I could buy the materials cut to size, (and I already have all the taps needed and some funky hex head bolts left over from another project) I’m sure I could bring in the case for far less than £154 even with my time.

The problem is I can’t put my money where my mouth is just yet as all my equipment is packaged up ready for the imminent MOVE FROM HELL ! lol.
But I would like to get your thoughts on this and if anyone can supply the materials cut to size and give me a quote please. Front Panel Express files are attached.new_midget_FPE_files(1).zip

Quote Customer no. Supplier no. Method of payment Your order number Your VAT-ID no.
903503 26993 Credit Card
Pos Quantity Order no. Description Sum Discount Unit price Total
10 1 Creation of file: bottom.fpd - Thickness: 2,0 mm 29,21 € 0,0% 29,21 € 29,21 €
20 1 Creation of file: front.fpd - Thickness: 2,0 mm 30,91 € 0,0% 30,91 € 30,91 €
30 1 Creation of file: rear.fpd - Thickness: 2,0 mm 35,75 € 0,0% 35,75 € 35,75 €
40 1 Creation of file: top.fpd - Thickness: 2,0 mm 33,71 € 0,0% 33,71 € 33,71 €
50 2 GLGP1021 Side profile 2, anodized, Length: 254,0 mm 6,33 € 0,0% 6,33 € 12,66 €
60 1 GGMS1102 Assembly kit ISP/B3.0-ZI DIN 7982, white galvanized
consists of 8x countersunk head screws ø2.9
x 9.5 mm and 4 self-adhesive rubber feet ø8
mm, height 2.5 mm
2,17 € 0,0% 2,17 € 2,17 €
Shipping costs: 'UPS Standard': 6,95 € 6,95 €
Subtotal 151,36 €
VAT (19,0%) of 151,36 € 28,76 €
Invoice amount 180,12 €

[Tenson]

Why not get a pre-made case?

Something like this - JC229 Aluminum Power amplifier Enclosure AMP Case DIY | eBay

[Fivetide]

Why not get a pre-made case?

Something like this - JC229 Aluminum Power amplifier Enclosure AMP Case DIY | eBay

Hi mate yes thats the exact one I have book marked on ebay, I'am thinking about it tbh, but was also fishing for answers :) Also the face plate wont match the holes .

[IanS1]

These folks do some nice cases; modushop.biz or buy the ebay one and get a new face plate made.

I've been looking at building one of Pete's amps for a while. The very tempting KT88 push-pull: Push-pull KT88 class A amp with "universal" driver PCB

[Tenson]

Ask them about a face-plate without holes so you can mill it yourself. They have faceplates for other boxes without holes.

Also, the switches and volume can be wired on, rather than PCB mounted.

P.S. Is there a reason you want a valve amp, rather than just a nice small amp? I have a friend who makes / sells a nice amp PCB. H.T. Baker Audio - HB7 Amp He also makes an output transformer emulator, which makes the amp behave like a valve one.

[Fivetide]

These folks do some nice cases; modushop.biz or buy the ebay one and get a new face plate made.

I've been looking at building one of Pete's amps for a while. The very tempting KT88 push-pull: Push-pull KT88 class A amp with "universal" driver PCB

Nice cases , thanks. I had thought about the KT88 but for my Dad as he had an old Valve amp years ago I thought he would like it.

Ask them about a face-plate without holes so you can mill it yourself. They have faceplates for other boxes without holes.

Also, the switches and volume can be wired on, rather than PCB mounted.

P.S. Is there a reason you want a valve amp, rather than just a nice small amp? I have a friend who makes / sells a nice amp PCB. H.T. Baker Audio - HB7 Amp He also makes an output transformer emulator, which makes the amp behave like a valve one.

Wow that’s a great site mate; I have a 120 toroid out of a scrapped Arcam, may well be worth considering that for my next project. I saw some quad DIY on eBay then decided to search DIYaudio for any threads on them, I was amazed how much hassle they were to actually make ready to use ! So I ditched that idea, if the one on the site are out of the box with a bit of wiring then they are well worth a look at.
I think the real purpose of the thread is to see if I can make the Midget case at a low enough cost to sell them and make a decent profit. I’m always looking for ways to make money from my CNC. I just thought that I could make one for far less than £150.

[Tenson]

You surely can make the cases cheaper, but don't forget finishing.

The HB7 amps are only sold as ready to roll PCBs, so yes it's just a case of connecting a transformer and putting it in a case. Here is one in a nice case.