Holco H8 resistors

[ALW]

A question for those who know.

I believe the earlier version of the Holco H8 resistors were of a totally non-ferrous construction, but that later versions had steel / ferrous endcaps ?

Can anyone offer any means of determining which type is which, without resort to actually obtaining some and giving them the magnet test.

I have a disti that's closing out what may be old stock. I've asked for data sheets and they onle mention the lead material, not the end-caps - does anyone have an old data sheet for comparison?

Any help will be gratefully appreciated.

Andy.

[tiroth]

You are correct that the older Holco are non-ferrous. Welborne Labs still has a stock of some of these and may be a source of info.

Also, this is extremely non-scientific, but of the Holcos I have, the newer magnetic ones have the black coating applied over the endcaps and spilling onto the leads. My NOS ones have clean leads.

[ALW]

Data I've found on the web talks about gold-plated endcaps, but the data sheet the disti sent me doesn't mention this in any way.

I think I'll buy a few and test the waters, you wouldn't believe what a pain buying non-mag resistors is in the UK!

Andy.

[jam]

Andy,

One caution about the old style Holco, they seem more fragile mechanically than most and sonically a bit soft on the high end, otherwise they were an excellent choice.

Regards,
Jam

P.S. I have now swiched to Dales and am very happy with the results.

[ALW]

One caution about the old style Holco, they seem more fragile mechanically than most and sonically a bit soft on the high end, otherwise they were an excellent choice.

Jam,

Thanks for that, the Dales are great, and I've only heard one type that's better (a special audio-grade device that's new to market and generally unailable at present), but the Dale's are a pain to buy in the UK too, unless anyone out there has any ideas for sensible priced disti's. I'm looking to buy in the US (Mouser), but import duties and carriage can be a pain.

I've been using the RN60 series but these are not guaranteed non-mag anymore, the new parts in primary values have steel endcaps - you have to buy odd values, or mil-spec parts (RNC / ELR or ERC) at MUCH greater price to be certain.

I'd be VERY grateful for ideas and alternatives though, this is driving me mad at present, the sonic signature of the Beyschlag parts I normally use is so obvious after the Dale's.

Andy.

[jam]

Andy,

I am looking at some surface mount resistors next (pain to solder)
but have very low inductance. They promise a tighter layout with some sonic benefits.

Regards,
Jam

[Brad Pontow]

Be interested to see if you can find any smd resistors that sound decent. They ones I have run across have been dreadful

[ALW]

Jam,

I've looked at SMD too, as I have no problems working in that form, but the initial trials of some Neohm 0805 1%, 1/8W ones was unconvincing.

The layout opportunities are a big bonus, so I wonder about the larger format devices (1206 upwards).

Most use nickel as a barrier though, those that don't are intended for bonding, not soldering.

DACT use NM SMD devices in their attenuators though, but I've not determined the type.

Andy.

[jam]

Andy,

I will let you if I find anything worth using. You might be right, that larger format devices might work better.

Regards,
Jam

[fdegrove]

Hi,

One caution about the old style Holco, they seem more fragile mechanically than most and sonically a bit soft on the high end, otherwise they were an excellent choice.

As far as the sound of these Holcos go I agree 100%, they tend to sound too sweet for comfort.

Bet that does show up on a scope either?

Ah well, it's their loss no?

Cheers fellows.