Overview

Nice work, Greg. Can you share what you do to "de-rust"..., do you use mechanical or chemical derust techniques? My mother just gave me the old Fisher amp that I grew up with..., and she had it in her basement. My first look at it, and I realized the basement humidity had done a similar light rusting to your hafler...

Very nice - that amp was pretty crusty.

A received a Hafler DH-220 to fix along with an extensive upgrade kit. It came with a USB drive with docs and pics. A well put together project. The unit was in dire need of service. Old, crusty, and very dirty. Top of unit: Near power switch and primary fuse: Taken apart: I removed most of the screws and derusted them, then cleaned and derusted the chassis, heat sinks and other various parts. It was a load of work! But it cleaned up pretty good. All new amp driver boards that had to be stuffed by hand. Crazy! New speaker binding posts and RCA jacks as well. It looks so much better now though: Sorry - forgot to snap a picture of it all put together. But here's an internet one:

Really sweet. The gold-plated ground screw is a very nice touch.

Do you ship to China? 😁

We can do that... C-4000 C-1

Problem: Main reservoir capacitors venting Solution: Full restoration! The main reservoir capacitors on the 5ch and 7ch models have reached their end of their usable life. They will boil, and vent - possibly causing permanent damage to surrounding circuit boards. Electrolytic fluids are corrosive. Furthermore, if these large main capacitors fail, they can damage the power supply by shorting to ground on one side, in a normally balanced supply. In most cases, the main fuse will blow from the failing capacitor, but there is no guarantee.

Problem: Severe burning of the PCB around regulator circuits on dual channel boards that can lead to permanent damage Solution: Full restoration! The regulator circuits need to be rebuilt and modified to prevent future burning. Without service, these amps can be become UNUSUABLE.

Makes one concerned about shipping when buying one of these, and it's going to be packed and shipped by someone that ..., has no idea.

Make sure the power transformer is as secure as possible. Tighten the 4 large screws on the bottom of the chassis until they are snug. If the transformer still feels loose, pop the top and tape some cardboard over the transformer top, just enough to fit under the metal cover. Or this can happen:

I have had two clients inquire in just the past week reporting that their (unserviced) Sunfire amp has blown the magic smoke and needs repair. This is becoming more common. Please get the word out that Sunfires need to be serviced. If they blow smoke/catch fire the service becomes more expensive - if it's even repairable. Last year, someone sent me a burned up unrepairable TGA-5400. Gorgeous, rare amplifier...gone. So I think it's time for a reality check. Many Sunfires are too old to gamble with. They have substantial power and self-destruct rather violently - more so than I think people expect. Also, be wary of local repair shops. Sunfires are not easy to work on (even we have to use specialized equipment) and most techs out there do not understand how they work. So it's also common for us to get Sunfires that were not repaired correctly from local shops.

Sold! I was going to refresh my C-1 myself and do the Bill D mod. After hearing this, I'm going to hold off on doing any of the C-1 work myself and send it to you guys. But I'll wait a few weeks after I get my M-1.0t back from your shop. I want to enjoy that for a bit.

First, the hardware is integrated with the C-1, so there's no external box. Second, this hardware is not just bluetooth, but also connects to your wi-fi so you can stream via Spotify, Apple Music, etc. And it will stream music from a NAS or PC that uses the DLNA protocol. Many home routers have a USB input, so you could connect an external USB harddrive full of music to your router USB, and this hardware will stream music from that as well. This is all done though the phone app that connects to the hardware.

Intriguing idea! I'm especially interested in direct streaming to my C-1. Without giving away any secrets, how would it differ from something like this (I currently use one): https://www.amazon.com/dp/B016NUTG5K?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_20 Lastly, in your minds eye, when do you see this available to the general public? Definitely a cool idea!

They sounded amazing! Worth their weight in, well, weight! LOL They are heavy buggers.

Bluetooth and Wifi will be available for the C-1 and C-4000 and many other preamps! The testing is working out fantastic! The app we use will make your phone able to stream bluetooth directly to a C-1, as well as Apple Music, Tidl, Spotify, and many other integrations. It will also play music directly from your NAS or DLNA enabled PC! I love this integration!

Great post! I'm still evaluating the applications. All will integrate with Alexa and Google though - it's pretty common now. As much as I would like to be able to accommodate each well known automation company, it's just too expensive and too much to deal with on our end. My decision will be based on a single application with a wide variety of devices that's been around long enough to have a good track record - I'm down to two. I'm extremely excited about the VCC. I've been working on the idea for a couple of years. It will hopefully be that one stop solution to take care of a variety of modern needs that many people just don't have any desire to shop for - like surge protection, AC line filtering, power switching, etc. The VCC will also have a DC blocking filter for toroid transformers. I've also toyed with the idea of making it an amp cooler by installing quiet fans under the top cover to blow up into a power amplifier stack above...

I am highly interested in following this thread. I implement home automation in my home, and currently my vintage gear power is switched, through automation, using Ubiquiti Unifi smart power strip. ESP32 is used extensively within Home Assistant as well, and within many other smart devices on the market. The point is, when designing this solution, look at compatibility with smart home interfaces using off-the-shelf technology. I can tell you after having a smart phone for 20 years, I simply tire of having to rely on it solely to control devices. Automation ability with Home Assistant, Alexa, Google, etc, would be a nice value add. I would certainly buy the Vintage Control Center in a heartbeat, most likely as a standalone device, but more so if implemented as a modern piece of gear.

Very cool idea on the phone app - I'll be looking forward to learning more about that.

For 2025 we will be introducing new mods that will allow you to use a phone app to control functions like volume, power on/off, and filters on common Carver models. We will also be introducing a new product called the 'Vintage Control Center' which is a power sequencer, surge protector, conditioner, and a general integrator of your vintage rack to make it work more seamless with newer technology. At the touch of your smartphone screen, you will even be able to control the volume of source units or preamps that otherwise do not have this feature. I have toyed with the idea of including an inverter to a power amp input channel which would allow some amps to be used as common ground and others to be used in bridge mode.

Please go HERE to see our Christmas Giveaway 2024! Woohoo!

Saw this over on Facebook... https://www.facebook.com/share/p/15a2dWdYRh/ Some cool pictures of Greg with Bob Carver on a recent visit. Would love a pair of those amps!!

I would be interested in getting more information about this upgrade in particular for the Sunfire Signature Stereo II Amp. Additionally, I have a Sunfire Theater Grand IV that has decided to output a nasty hum in all settings, thoughts on repairs? Thank you in advance for your feedback and assistance. v/r Kurtis Nold

We will be at Carverfest, then on to Texas for the first half of September. We will still have someone available here at the shop though. I also plan on keeping up with emails and phone calls.

Great to hear.