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Posted: 06 Sep 2007, 16:29
by guisquil
Thanks,
G
JHS wrote:Use a 1N4148 instead of the 1N400x and drop the 1M pulldown R, it's not in the COT and only sucks tone. The rest is the COT...
JHS
Posted: 21 Sep 2007, 12:53
by guitarquiz
I has the old sunburst one too no Volume and no DC terminal on Ext. power supply. Can use only Battery. Sound good but need a volume control.
Posted: 26 Sep 2007, 18:07
by neilnil
Posted: 11 Oct 2007, 18:45
by DougH
analogguru wrote:After listening to the soundclips I am wondering if $229,--:
I've listened to the clips a few times and it all sounds pretty run of the mill to me. Nice guitar playing and all but there's nothing in the sound of it that sounds particularly unique or appealing, to me.
Posted: 28 Oct 2007, 07:32
by sosodef
Is this the cot50?
I might build it just for fun. The cot50 I played was total junk. Is there any suggestions for mods or such just to make it sound better? I could use the practice anyway.
Posted: 28 Oct 2007, 09:34
by JHS
You can mod the COT50 circuit and IMHO it sounds much better after some modding but the treble is always thin and peaky.
My clone has a BC109C, a 5,6n I-cap, 2,2M CC pulldown Rs, and the 2,2M FB-R is CC to. Diodes are 1N914 and 1N4003.
All in all it sounds better but not as good as some other boosters I built.
For me any Ge-trannie boost w/o diodes sounds better and way more natural.
I never recommend to build or to buy The COT50. IMHO cloning the COT is a waste of time.
JHS
Posted: 03 Nov 2007, 11:25
by jakerandall
Couldn't you build a similiar or even better sounding COT50 without the silicon? Something op-amp based or with mosfets? Its such a simple design but surely there has to be a better way to achieve that sound and better without reverting to silicon.
Posted: 07 Nov 2007, 07:43
by hotguit
Hi
I'm making the pcb with Eagle.
I'll post it asap
bye
Hot
Posted: 07 Nov 2007, 07:49
by bigPIMP
JHS wrote:You can mod the COT50 circuit and IMHO it sounds much better after some modding but the treble is always thin and peaky.
My clone has a BC109C, a 5,6n I-cap, 2,2M CC pulldown Rs, and the 2,2M FB-R is CC to. Diodes are 1N914 and 1N4003.
All in all it sounds better but not as good as some other boosters I built.
For me any Ge-trannie boost w/o diodes sounds better and way more natural.
I never recommend to build or to buy The COT50. IMHO cloning the COT is a waste of time.
JHS
I totally disagree.. 5.6 N I cap mushes out WAY too much on chording for my tatses.. waste of time ah? LOL!
diodes are wrong too here..
Posted: 07 Nov 2007, 14:50
by gtrwrks
Maybe an SMD version would be better, no?
Posted: 08 Nov 2007, 08:48
by bigPIMP
gtrwrks wrote:Maybe an SMD version would be better, no?
yup..
did it, done, ready to go.. no goop too.. now I can retire.
Posted: 08 Nov 2007, 20:19
by Lovepedal Detective
Wait until the first guy on TGP gets one. It will be a treat to watch them get whipped up like the E thread.
LPD
Posted: 21 Nov 2007, 01:34
by Shitty Medeocre Tone
Posted: 23 Nov 2007, 11:34
by snail
A friend of mine and myself were not quite getting the same sound ABing the real COT50 and the one we built using the schematics suplied so far.
So he degooped it just for kicks and found two important details:
1) input cap is 47nF, not 4,7.
2) back to back diodes are Ge 1N60 not 4148, although they look a lot like the 4148, coz they're really small clear glass with black stripe. The pair measures 27K back to back.
The yellow cap is a multilayer 473 substituted for a greenie 473 (original) busted in the process.
snail
Posted: 23 Nov 2007, 11:51
by cbriere
try measuring the diodes on the meter "diode"position
then you will notice right away,
Meter gives 0.3v for GE diode and 0.7 for SI .
Posted: 23 Nov 2007, 13:10
by snail
It's Ge!
i know 0,3 for Ge, 0,7 for Si, 1,6... for leds and all. The fact is that measuring them back to back it yelds 27K ohm of resistance, typical of the 1N60 (which IME ranges from 25 to 32 in this measure that I do).
And It nails the COT sound ABing them, done it. Si don't do it.
Ah, IMO the BC239B sounds better than the 5088 in this circuit.
Posted: 23 Nov 2007, 13:42
by analogguru
....although they look a lot like the 4148, coz they're really small clear glass with black stripe.
If they look like the 4148 I would assume that the diodes could be schottky-diodes.
analogguru
Posted: 23 Nov 2007, 19:13
by $uperpuma
I've got some of those 1n60s and they sound great in simple circuits like this...
Posted: 24 Nov 2007, 01:36
by guiltyspark
snail wrote:A friend of mine and myself were not quite getting the same sound ABing the real COT50 and the one we built using the schematics suplied so far.
So he degooped it just for kicks and found two important details:
1) input cap is 47nF, not 4,7.
2) back to back diodes are Ge 1N60 not 4148, although they look a lot like the 4148, coz they're really small clear glass with black stripe. The pair measures 27K back to back.
The yellow cap is a multilayer 473 substituted for a greenie 473 (original) busted in the process.
snail
Nice work, thanks for sharing!
Posted: 26 Nov 2007, 06:27
by Blues Lyne
Snail,
Just curious, what version of the COT was this?
I've seen another COT schematic that had a 1k pot then 470 ohm resistor paralleled with a 22uF cap between the emitter and ground. Is the emitter to ground portion of the schematic you posted what you found in your friends COT? Or, is it just there from the previous schematic?
Also, I think JHS said previously that the COT didn't have the 1M resistor. Was there one in there?
