PANDA Headphone amp kit, build thread, upgrades & tweaks.

[PinkFloyd]

Apr 3, 2013 12:38:53 GMT oldson said:

Mike
just got some phono sockets from maplin and they look shite compared to the ones you fitted.
could you please post a link to a supplier?
cheers

You got these: www.rapidonline.com/Cables-Connectors/RVFM-PCB-Phono-Connector-Black-28543

I think these are even better: www.rapidonline.com/Cables-Connectors/Gold-Plated-Mounted-Phono-Sockets-521146

[PinkFloyd]

Let me have a look..... I may have a couple kicking about Simon

Mike.

[PinkFloyd]

Apr 3, 2013 12:50:04 GMT PinkFloyd said:

Let me have a look..... I may have a couple kicking about Simon

Mike.

Yep.... got one red and one black.... the same type that's fitted to your Panda already Good quality sockets.

[oldson]

Apr 3, 2013 12:54:05 GMT PinkFloyd said:

Apr 3, 2013 12:50:04 GMT PinkFloyd said:

Let me have a look..... I may have a couple kicking about Simon

Mike.

Yep.... got one red and one black.... the same type that's fitted to your Panda already Good quality sockets.

Mike
thats brilliant, will take the crap maplin ones back.
how much do you want for them?

[oldson]

Mike

one more thing i would like advice on please.
the following toggle switch,i know, is way overkill for this....
www.maplin.co.uk/10a-toggle-switches-2360

thing is , i plan on using the unused HP socket hole to mount the input switch as i do not wish to drill a further hole in the faceplate.
the "miniature" toggles will look silly (imo) on the front of this amp, plus i imagine the existing hole diameter is 12mm and would mean a mini toggle would need washers to fit, again this would spoil the look of the amp.

do you know if the above maplin switches are good quality or should i look elsewhere?
thanks mate

[Crispy]

Apr 3, 2013 16:21:42 GMT oldson said:

Mike

one more thing i would like advice on please.
the following toggle switch,i know, is way overkill for this....
www.maplin.co.uk/10a-toggle-switches-2360

Hi Simon,

Loads of toggle switches here:
www.rapidonline.com/SearchResults.aspx?kw=toggle+switch&srb=0&dir=0&cat=5490&icl=1&pg=1

www.ebay.co.uk/sch/i.html?_nkw=toggle+switches&_sacat=0&_odkw=togle+switches&_osacat=0&_from=R40

[PinkFloyd]

Apr 3, 2013 15:17:59 GMT oldson said:

Apr 3, 2013 12:54:05 GMT PinkFloyd said:

Yep.... got one red and one black.... the same type that's fitted to your Panda already Good quality sockets.

Mike
thats brilliant, will take the crap maplin ones back.
how much do you want for them?

Call it a tenner shipped

PM me you details again Simon and I'll pop them in a jiffy bag.... the "red" one is very rare, you can only buy "black" from Rapid these days

[oldson]

Apr 3, 2013 18:40:33 GMT PinkFloyd said:

Apr 3, 2013 15:17:59 GMT oldson said:

Mike
thats brilliant, will take the crap maplin ones back.
how much do you want for them?

Call it a tenner shipped

PM me you details again Simon and I'll pop them in a jiffy bag.... the "red" one is very rare, you can only buy "black" from Rapid these days

payment sent twice i think

dont know if 1st one went through as pc rapped its hand in at the crucial moment.

thanks Mike

[PinkFloyd]

Apr 3, 2013 16:21:42 GMT oldson said:

Mike

one more thing i would like advice on please.
the following toggle switch,i know, is way overkill for this....
www.maplin.co.uk/10a-toggle-switches-2360

thing is , i plan on using the unused HP socket hole to mount the input switch as i do not wish to drill a further hole in the faceplate.
the "miniature" toggles will look silly (imo) on the front of this amp, plus i imagine the existing hole diameter is 12mm and would mean a mini toggle would need washers to fit, again this would spoil the look of the amp.

do you know if the above maplin switches are good quality or should i look elsewhere?
thanks mate

I would keep that spare headphone socket intact if I were you, you'll be glad it's there when you start playing about with different impedance outputs

Good reasons for mounting the switch on the back panel:

A: Easier to drill through the thinner back plate

B: Signal wiring kept to a bare minimum

C: Signal wiring kept away from the PSU section of the amp.

You can whip out that 3.5mm input socket on the back plate and fit the switch there? It will be easy to bore a bigger hole thanks to the pilot hole of the 3.5mm socket.

The Maplin switches are fine, Rapid also do them.

Something like this would also do: www.hificollective.co.uk/catalog/tape-source-switch-p-6209.html

Hope this helps.

Mike.

[oldson]

Apr 3, 2013 17:53:18 GMT Crispy said:

Apr 3, 2013 16:21:42 GMT oldson said:

Mike

one more thing i would like advice on please.
the following toggle switch,i know, is way overkill for this....
www.maplin.co.uk/10a-toggle-switches-2360

Hi Simon,

Loads of toggle switches here:
www.rapidonline.com/SearchResults.aspx?kw=toggle+switch&srb=0&dir=0&cat=5490&icl=1&pg=1

www.ebay.co.uk/sch/i.html?_nkw=toggle+switches&_sacat=0&_odkw=togle+switches&_osacat=0&_from=R40

thanks mate, found one on ebay link.
just trying to find it a tad cheaper now ,as they are more than i wanted to pay.
www.ebay.co.uk/itm/140941912416?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

i think farnell stock these so will try them later

[PinkFloyd]

Apr 3, 2013 18:50:37 GMT oldson said:

Apr 3, 2013 18:40:33 GMT PinkFloyd said:

Call it a tenner shipped

PM me you details again Simon and I'll pop them in a jiffy bag.... the "red" one is very rare, you can only buy "black" from Rapid these days

payment sent twice i think

dont know if 1st one went through as pc rapped its hand in at the crucial moment.

thanks Mike

I'll accept both payments

hehe....... I'll go check and refund you accordingly

[PinkFloyd]

Apr 3, 2013 18:54:33 GMT PinkFloyd said:

Apr 3, 2013 18:50:37 GMT oldson said:

payment sent twice i think

dont know if 1st one went through as pc rapped its hand in at the crucial moment.

thanks Mike

I'll accept both payments

hehe....... I'll go check and refund you accordingly

Yeh, you sent two seperate payments..... have just refunded one of them

Mike.

[PinkFloyd]

Apr 3, 2013 18:53:40 GMT oldson said:

Apr 3, 2013 17:53:18 GMT Crispy said:

Hi Simon,

Loads of toggle switches here:
www.rapidonline.com/SearchResults.aspx?kw=toggle+switch&srb=0&dir=0&cat=5490&icl=1&pg=1

www.ebay.co.uk/sch/i.html?_nkw=toggle+switches&_sacat=0&_odkw=togle+switches&_osacat=0&_from=R40

thanks mate, found one on ebay link.
just trying to find it a tad cheaper now ,as they are more than i wanted to pay.
www.ebay.co.uk/itm/140941912416?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

i think farnell stock these so will try them later

If you can wait a day or so I'll check through my switch armoury and sort you out a really decent one

Good to see you getting to grips with the Panda Simon, glad it's gone to a good home.

Mike.

[oldson]

Apr 3, 2013 18:52:57 GMT PinkFloyd said:

Apr 3, 2013 16:21:42 GMT oldson said:

Mike

one more thing i would like advice on please.
the following toggle switch,i know, is way overkill for this....
www.maplin.co.uk/10a-toggle-switches-2360

thing is , i plan on using the unused HP socket hole to mount the input switch as i do not wish to drill a further hole in the faceplate.
the "miniature" toggles will look silly (imo) on the front of this amp, plus i imagine the existing hole diameter is 12mm and would mean a mini toggle would need washers to fit, again this would spoil the look of the amp.

do you know if the above maplin switches are good quality or should i look elsewhere?
thanks mate

I would keep that spare headphone socket intact if I were you, you'll be glad it's there when you start playing about with different impedance outputs

Good reasons for mounting the switch on the back panel:

A: Easier to drill through the thinner back plate

B: Signal wiring kept to a bare minimum

C: Signal wiring kept away from the PSU section of the amp.

You can whip out that 3.5mm input socket on the back plate and fit the switch there? It will be easy to bore a bigger hole thanks to the pilot hole of the 3.5mm socket.

The Maplin switches are fine, Rapid also do them.

Something like this would also do: www.hificollective.co.uk/catalog/tape-source-switch-p-6209.html

Hope this helps.

Mike.

sounds like good advice, i did not think of signal wiring.
looking at the switch you have recommended i guess the cheaper minis from maplin would not suffice??
www.maplin.co.uk/sub-miniature-toggle-switches-2341#specification
i certainly dont want to affect the sound quality.

[oldson]

Apr 3, 2013 19:00:34 GMT PinkFloyd said:

Apr 3, 2013 18:53:40 GMT oldson said:

thanks mate, found one on ebay link.
just trying to find it a tad cheaper now ,as they are more than i wanted to pay.
www.ebay.co.uk/itm/140941912416?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

i think farnell stock these so will try them later

If you can wait a day or so I'll check through my switch armoury and sort you out a really decent one

Good to see you getting to grips with the Panda Simon, glad it's gone to a good home.

Mike.

HaHa
i cant post as quickly as you.
if i have paid twice keep both and let me know if you want more for the switch.
i am in no hurry, as i am away tomorrow anyhow, thanks mate

[PinkFloyd]

In the meantime........... up the voltage across the 1K5 resistors to 1.5V and then re-trim the DC offset..... that will keep you occupied and give you a feel for trimpot adjustments....... I shipped the Panda with 1.35V KNOWING that it can be even better sounding @ 1.5V...... thought I'd let you get some hands on and experience it yourself

Mike.

[PinkFloyd]

You've got a multimeter?

[oldson]

Apr 3, 2013 19:11:14 GMT PinkFloyd said:

You've got a multimeter?

yeah i have a meter.
i am a lift engineer ,so i have one provided by my company.
i know my way around basic electrical drawings, but not down to circuit boards, if that makes sense?
have had some experience adjusting pots on variable frequency drive units, but these days it is done through a user interface panel rather than using the meter.

willing to give it a go, though.

[oldson]

as far as output power is concerned, would the panda "get the best out of" , for instance the hifiman he6?
i am in the market for an open headphone.
i have read the he-6 is best driven by a speaker amp.
cheers

[joethearachnid]

I can't say for the HE-6 directly, but I tried the HE-4 (which I've heard some people say is harder/as hard to drive since it only has one magnet per driver instead of two) and the Panda coped pretty well. Comfortable listening at about 3 o'clock with 110ohm output resistors and about 12 o'clock with no output resistors. I daresay that the Panda would do fine with the HE-6 - whether it would drive them to absolute peak potential I can't say, but I wager it'll do a damn good job.

-JoetheArachnid

[oldson]

Nov 7, 2010 17:09:55 GMT @solderdude said:

Nov 7, 2010 17:01:39 GMT mrarroyo said:

Mike, have you measured the output in mW of this amp? Thanks.

What output resistors does it have and which HP (impedance) do you want the numbers for.
The power levels are dependant of those 2 values.

Here are the powers for a Panda with a NO (0 Ohm) output resistor (rounded off values):

HP impedance ....Class-A......Class-AB
32 Ohm ..............640mW.......3,125mW
64 Ohm ..............1,280mW ...1,560mW
150 Ohm ............670mW ......670mW
300 Ohm ............330mW ......330mW
600 Ohm.............170mW ......170mW

Here are the powers for a Panda with a 10 Ohm output resistor (rounded off values):

HP impedance ....Class-A......Class-AB
32 Ohm ..............640mW.......1,800mW
64 Ohm ..............1,170mW ...1,170mW
150 Ohm ............580mW ......580mW
300 Ohm ............310mW ......310mW
600 Ohm.............170mW ......170mW

Here are the powers for a Panda with a 22 Ohm output resistor (rounded off values):

HP impedance ....Class-A......Class-AB
32 Ohm ..............640mW.......1,100mW
64 Ohm ..............640mW ......870mW
150 Ohm ............510mW ......510mW
300 Ohm ............290mW ......290mW
600 Ohm.............160mW ......160mW

Here are the powers for a Panda with a 47 Ohm output resistor (rounded off values):

HP impedance ....Class-A......Class-AB
32 Ohm ..............500mW.......500mW
64 Ohm ..............500mW ......500mW
150 Ohm ............380mW ......380mW
300 Ohm ............250mW ......250mW
600 Ohm.............140mW ......140mW

Here are the powers for a Panda with a 75 Ohm output resistor (rounded off values):

HP impedance ....Class-A......Class-AB
32 Ohm ..............280mW.......280mW
64 Ohm ..............330mW ......330mW
150 Ohm ............300mW ......300mW
300 Ohm ............210mW ......210mW
600 Ohm.............130mW ......130mW

Here are the powers for a Panda with a 120 Ohm output resistor (rounded off values):

HP impedance ....Class-A......Class-AB
32 Ohm ..............140mW.......140mW
64 Ohm ..............190mW ......190mW
150 Ohm ............200mW ......200mW
300 Ohm ............170mW ......170mW
600 Ohm.............120mW ......120mW

So pick your headphone impedance and you will have a pretty good idea.

NOTE: Most headphones can handle a power of around 100mW to 200mW.
You can clearly see that a higher output resistance of the amp leads to safer values for all headphones where 0 Ohm or low Ohmic values can seriously overdrive (destroy) low Ohmic headphones !
High Ohmic headphones are always in the 'safe zone' with this amp.
Amps with a 120 Ohm output resistor in the output are also always in the 'safe zone'.
Some headphones, however, perform sonically better at lower output resistances but you must be aware that these low output resistance values can destroy low Ohmic headphones.


are the goalposts moved again when using the LCD2 for example, surely these could handle the panda with no output resistor, or am i missing the point?

[invidiy]

Hello, maybe it's a wrong thread to ask but has anybody had any problems registering/buying a Panda kit recently? I tried to make an account at mall.hifidiy.net but have never received a confirmation letter, hence, can't shop. Tried to contact them via both support emails and the page form but they've never responded, it's been almost 3 weeks since my first mail. Any clues what's going on with them?

[pingu]

May 1, 2013 1:55:42 GMT invidiy said:

Hello, maybe it's a wrong thread to ask but has anybody had any problems registering/buying a Panda kit recently? I tried to make an account at mall.hifidiy.net but have never received a confirmation letter, hence, can't shop. Tried to contact them via both support emails and the page form but they've never responded, it's been almost 3 weeks since my first mail. Any clues what's going on with them?

Hi invidiy,
try "panda pcb" search in Ebay and you should come up with two sellers, both buy it now options, post free to most places
Martin

[invidiy]

pingu, thanks, might try that option if it fails with hifidiy.net, because the idea was to get a full kit with the case. They seriously need to hire someone to deal with support inquiries.

[PinkFloyd]

I've got half a dozen of these kits kicking about but they are PCB and parts only.

Mike.